Ode to the Air Cooled

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No new cars – and just a dwindling handful of new motorcycles –  have engines that rely on the air to cool them.

Technically, it’s airflow – which washes over the exterior surfaces of the engine (in some cases, is forced to wash over the exterior surfaces by an engine-driven fan – that’s you, old Beetle, old Corvair and also not-so-old Porsche) and that – along with oil – cools the engine.

Both transfer heat.

But no water is involved – which means no radiator; which means no water pump buried deep in the guts of the engine, or hoses or thermostats and (best of all) no road trip-ending leaks. Ever. As well as no ever needing to replace any of those many and often expensive parts – which the air (and airflow plus oil) cooled engine hasn’t got.

It also means easier access by dint of not having those extra parts bolted to it and all around it, which makes it easier to get at the engine.

Well, sometimes.

Air-cooled motorcycle engines are easy to get at. They usually hang in the breeze – literally.

The necessity of this – airflow, remember – means not covering the engine with . . . covers. The air-cooled motorcycle engine is generally just there.

Accessible – and visible.

You can lay hands on almost all of it without tools – without having to remove a bunch of peripheral parts first.

This has the additional benefit of looking good – the industrial art of fins and castings, alloys and chrome plating. An air-cooled engine is a work of art that works.

Sometimes, the beauty is hidden beneath tinwork and shrouds – as in the old Beetle, as well other old air-cooled cars like the Chevy Corvair and, of  course, classic (and even fairly recent) Porsches.

This is both for cooling and heat.

This time, to conserve it and use it.

Remember: No radiator; thus, no warm coolant to warm up the car’s interior – so no warmth (for the car’s occupants) when it’s cold outside. Thus, in an air-cooled car, the necessity (absent an accessory gas heater or some other apparatus) for not letting all of the engine’s heat just waft away into the air (as it does on an air-cooled bike, which doesn’t matter because there is no interior to warm up).

Instead, air heated by the engine is captured – and redirected to the car’s cabin, cozying up the joint.

The idea not only kills two birds with one stone (cools the engine by taking it away from the engine; warms the car’s interior by directing the engined-warmed air into the passenger compartment) it is also faster.

Water-cooled engines take longer to warm up – because they have thicker blocks and cylinder heads (to accommodate water jackets/cooling passages) and because it takes a while for engine heat to build and transfer to the liquid medium (the coolant) and eventually – it often seems like an eternity on really cold days – provide warmth for the passengers.

Air-cooled engines warm up much faster.

Their castings tend to be thinner and there’s no need to heat up a medium (the liquid, in air-cooled engine)  to transfer the heat of combustion to the passenger compartment. If you’ve had the good luck to drive an air-cooled car in winter you know the heat works almost as soon as you turn the key.

Well, assuming the tinwork is tight – and the fan is working correctly. Air-cooled (and heated) Beetles have a rep for being drafty but it’s really the result of being old and not in good repair. No one denounces air-cooled Porsches for coldness, which is usually because Porsches are better cared-for than old Beetles.

The concept remains sound, is the point. Arguably, sounder than the water-cooled concept, if the object  is to reduce complexity, ease serviceability as well as get warm quickly when it’s very cold out.

German cars were air-cooled for a reason. It gets cold in Germany.

So, what happened to the air-cooled concept? If it’s such a sound concept, how come it’s almost extinct in terms of what’s available new . . . excepting lawn mowers and weed whackers, that is?

The former provides the clue that gives us the answer.

Lawn mowers and weed whackers aren’t – yet – subject to the degree of emissions regulations that cars and motorcycles are subject to.

Porsche was the last car company to offer an air-cooled car for sale, back in 1998.

Rather, Porsche was the last car company to be allowed to sell one. The rest – including VW’s air-cooled cars – had been forced off the market one by one by emissions regs that got progressively stricter to the point that complying with them became too expensive and too much hassle.

Even Porsche – with all its engineering know-how and (unlike VW) far less constrained by cost – the need to keep it cheap – eventually had to knuckle under to Uncle. This happened more than 20 years ago – when the last of the air-cooled 911s left the factory. Since then, all Porsches – all cars sold in the United States, period – have been water-cooled.

But why is it so hard to comply with the regs using the air-cooled layout?

The first reason is that air-cooled engines tend to run hotter than water-cooled engines and this creates emissions issues; or rather, different compliance issues.

Not major – but different.

Compliance requires sameness. One size fits all. The rules, you know.

The second – and related – reason is that it’s more of a challenge to regulate the operating temperature of an air-cooled engine than a water-cooled engine, which makes it harder to precisely control its emissions under all operating conditions.

There is a temperature sweet spot that engineers striving to comply with emissions fatwas seek; that sweet spot is easier to hit with water-cooling.

It’s not that air-cooled engines are “dirty.”

A fuel-injected, catalytic converter’d ’98 911 poses as much of a threat to air-quality as nekkid pictures of Hillary threatens to incite turgidity in healthy males. The problem is purely one of pedantry. The air-cooled 911 isn’t . . . compliant.

Which is a very different thing than being dirty.

The distinction is analogous to the charge of “dirtyness” leveled at VW’s diesels (water-cooled, for the record) which weren’t by any sane standard anything other than “non-compliant” – i.e., they didn’t quite comport with the regulatory minutiae in every Inspector Javert-esque detail, no matter how pedantic or immaterial to air quality – the equivalent of being issued a ticket for “speeding” 3 miles-per-hour faster than the arbitrarily posted limit.

Guilty, perhaps – but criminal? Only to an Inspector Javert.

It was enough to demonize them – and to eliminate them.

The precedent for that set decades prior, when low-cost air-cooled cars such as the Beetle  were regulated off the market.

Air-cooled bike engines are probably next.

Your push mower, too.

Just wait.

. . .

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    • Think of it this way: Poor Bill (and yeah, in that aspect, I feel sorry for him, but hey, he asked her to marry him, the dumb-ass) had to get under covers with that…CREATURE (from what lagoon?). If the rumors that it was Webster Hubbell that contributed the spermatozoa to make Chelsea (ewww…) aren’t true, then he had to have “hit that” at least a few times way back when! So…a little over 20 years ago, he decides to get frisky with Monica…now, was the somewhat chubby Jewess actually all that good looking? Not really…but in comparison to the “Hildebeast”, she was Miss America, and does have, in comparison, a more pleasing voice!

      • Doug, I have this spore theory…… I mean, I mean, there’s no way any procreative processes could occur in that crevasse, even if there were enough powerful drugs in the world to allow Slick Willy to scale Mt. Rodharm with his staff. (But I hear that a certain Macanudo still receives a Father’s Day card every year)

      • Bill has very low standards. He’ll fuck anything with a pulse. They didn’t call him the first black president for nothing!

  1. My air cooled Corvair Monza Turbo Spyder had a multitude of engine faults. But I attribute that to General Motors’ horrible parts and build quality rather than the engine design itself.

    Hey, you almost made it through a whole article without bringing up the VW Diesel Emissions Scandal. 🙂

    You came close.. over 90% of the way. Because you write such short paragraphs (which is, stylistically a Good Thing,) it was the 38th paragraph (by my count) before the subject came up.

    • It’s hard to believe now, but in the early 1960s General Motors was a hotbed of engineering innovation. The problem is that the company tended to bring these wonders to market half-baked, with the buying public being the beta testers. (The bean-counters didn’t help matters either.)

      • That seems to be how GM has always operated. Full to bursting with some of the world’s best and most innovative engineering talent, but simultaneously unable to find its collective derriere with both hands. It only got worse once the bean counters really started taking over after the first manufactured fuel crisis and mandating that everyone innovate the company way or not at all. I mean, they built the world’s first turbocharged series-production passenger car back when a turbo was a cool power-adder for sports cars and not a soul remover for economy cars, but at the same time they deliberately reduced their build quality because they thought it would save them money without reducing sales.

        • (In fact, it just hit me that this is a major part of why I hate modern cars so much. Even in a communist dictatorship, some genuine engineering talent and/or love of craft will occasionally sneak through and produce a car that’s at least vaguely interesting or car-culture-able, like the Russian Ladas or Czech Tatras. To really screw up the process of designing and building a car, you basically have to be trying to screw up. That’s where new cars have been since about 2008.)

          • Hi Chuck,

            This is gonna get me in trouble (again) but… the Soviet Union and Nazi Germany were at least masculine societies; they were run by men. America is run by women – who control men. Everything is now organized to defer to the female obsession with ssssssssssssssssaaaaaaaafety. Car design especially reflects this.

              • Hi Mark,

                Women are – biologically – the yin to the male yang. They have a different nature than men. This is not to say they lack free will – much less intelligence. That’s obviously untrue. But they do perceive and feel differently, by nature – just as men do, by nature. It is insanity to buck biology; to deny the fact of human nature.

                When men and women’s natures complement each other you have healthy families and communities. When men and women are alienated from each other – by the hideous idea of sameness – we get what we have. Which is a dying society.

                • eric, You’re so right. I lament giving women the right to vote. What was first on their agenda? Control. They aren’t live and let live creatures for the most part.

                  Women like that piece of paper from the state saying they have control over a man. It wasn’t always so and the state had nothing to do with it since it shouldn’t have.

                  We got to see a decade and a half of violence and demoralization of the entire country as soon as women got the vote.

                  We see a military that has become ineffective yet all-consuming due to giving everyone the right to be a soldier.

                  I read a great article by a woman who joined the military and thought she was in great physical condition which she was……for a woman. She said on her first forced march she saw the writing on the wall nearly immediately with the slowest male in the pack smoking her immediately. She might have had better luck without that old nasty 80 lb pack.

                  She said women being in the battlefield was just another bad thing men had to deal with. They weren’t fast or strong and couldn’t carry a man that was injured but often were carried by men.

                  I just don’t understand why so many women are so clueless as to the difference in the sexes and don’t celebrate it as men do.

                  I love women but I don’t want to work with them. I have many times in the past and if there’s going to be trouble of any sort it’s going to come from a woman. Hell, it’s not common for them to be able to recognize a joke.

                  Think about the things you say to your male friends and everyone knows it’s a joke. OTOH, it’s no joke for almost every woman (there are exceptions but few). Everything is literal for women. It shows in every aspect of life. How many women comedians do you see? There’s the occasional flash in the pan but for the long haul, they don’t last long for the most part.

                  Women wish they could find a “good” man, translated, a guy who’d support them as they want to be and they can control. Men want sex and then some good sleep. Women, when they want sex, need to analyze it afterward.

                  • The only female “comedians” I know of that had any success are either dykes like Ellen “DeGenerate”, a fat pig like Rosie O’ Donnell (also, from what I understand, eats from the other side of the buffet, makes me actually feel SORRY for any dyke), or some vulgar potty-mouth like Sarah Silverman. I can’t think of ANY comedienne in the same category as Jerry Seinfield and definitely not the late George Carlin.

                    • I loved Joan Rivers and Phyllis Diller.

                      Carol Burnett is another big name, but I never found her funny.

                      Cloris Leachman was another funny lady.

                      But yes, most women are not funny. Many are not even bright enough to take a joke.

                    • Even the “queen” of female comedy- Lucille Ball, was not funny, nor clever, nor witty. Desi Arnaz; and more so, William Frawley (Fred Mertz) were what made I Love Lucy a success.

                      But even she was miles ahead of any modern female “comic”, who are all either purveyoers of vulgarity, or at best, merely joke tellers.

                      For some reason which I can not figure out, I do like the old Mary Tyler Moore show.

                      I can’t stand Mary- with that artificial smile and just strange-looking face; and the show really isn’t funny- but yet I find it very “comforting” to watch.

                      And of course, with Ed Asner, Ted Knight and Gavin MacLeod, it’s hard to resist.

                      Even most females I know don’t seem to like female comics- except for Carol Burnett- whom I don’t find funny at all- Most of her stuff relies on very simple and obvious parody; stuff that was too simplisitic for me even as a child. She’s like the female equivalent of Jeff Dunham- but then I guess that cops, retards [I’m being redundant] and Somali refugees need stuff that they can “get” too……

                    • The Mary Tyler Moore Show was feminist propaganda. And yeah, her face did seem kind of odd.

                      I’ve watched some of Lucille Ball’s later shows and wondered to myself how she became so iconic.

                      It’s interesting. Many of the old shows I thought were decent as a kid are incredibly painful to watch now. Sitcoms, on average, just never age well. The only good sitcoms worth buying box sets on is Seinfeld and Three’s Company. Three’s Company is still very funny – full of clever, indirect jokes.

                    • Han,

                      Just about every show from the 70’s, on, has been feminist propaganda.

                      Even my beloved All In The Family was intended to push the liberal/feminist agenda into mostly conservative American households of the time- but it backfired!

                      Funny thing about MTM; at least the feminist creeps were honest:

                      I mean, by the end of the show, Mary’s past her prime and living alone; away from her family; just living in an apartment and living to work at her “career”- and her only friends are pretty much the people with whom she was thrown into contact with at work, and her neighbors. No kids; no husband; no house….

                      In her early 30’s, and things are only gonna go downhill from there…

                      What a depressing prospect! It’s amazing that anyone fell for all of this propaganda, seeing as they openly portrayed the end results of that lifestyle (and so on many other shows).

                      I used to love Three’s Company years ago. Bought the DVD set a few years ago…enjoyed going through it again for the memories….but sadly, it’s something I can’t watch over and over…so I sold the set.

                      I’m about due to go through Seinfeld again this winter.

                    • “It’s amazing that anyone fell for all of this propaganda, seeing as they openly portrayed the end results of that lifestyle (and so on many other shows).”

                      Remember the ending of Bob & Carol & Ted & Alice?

                    • Handler, I Love Lucy was written for her to be so stupid she was funny. She had the emotions of a child.
                      If you recall, she could fuck up a cannon ball with a rubber mallet.

                      Her hubby treated her as a child. I don’t know why anyone would desire that sort of marriage but it seemed funny just because she was an idiot…..back then. Now, it’s sad.

                      She wasn’t a comedian, just a good actor who played the written part well. I can’t help but think the part she played bothered her a great deal in real life.

                    • Eight,

                      What always struck me about I Love Lucy, even when I was quite young, is how she was always scheming against her husband and lying!

                      But of course, when a woman’s doing it, it’s portrayed as “cute” and “funny”.

                      If the roles had been reversed, Ricky would no-doubt have been labeled a manipulative monster.

                      We’ve become so desensitized to these propaganda tactics, that even we can look at such shows as being wholesome and innocent- and they can be enjoyable to watch, even though we know what’s going on- but it’s sad when ya think about it; that through the auspices of such things the collective minds of hundreds of millions of people have been subverted.

                    • Nunz, true enough. Lucy’s raisin detree was lying…..badly. Oh, she always “meant well”.

                      that show depressed me enough I couldn’t watch it with the rest of the family and don’t recall it being on when my father was home.

                      I will admit I’ve always been an anarchist. When I was young and a topic came up and it was mentioned something was illegal I’d ask why. I’d give an example(I was very well read)of how it was done 100 years before and wasn’t considered immoral or illegal. Then the grown-ups would say “You should have been born 100 years ago”. I never knew how to take that. But the idea of being born 100 years ago appealed a great deal to me.

                    • Ha! Same here 8,-about “You should’ve been born 100 years ago” (Or sometimes: “Boy, Grandpa would’ve loved you!” (Not that he didn’t- but he died when I was a toddler).

                      The individualist outlook has always just been natural to me- and maybe I took it seriously when they’d say that we were free and that this is a “free country”(LOL).

                      The only ruiles that ever made sense to me, were ones that mirrored actual morality, and therefore did not need any external enforcement.

                      Like: I don’t refrain from stealing from you because a cop is standing over me and it’s “against the law”; I refrain from stealing because I respect certain universal rights, such as property rights; nor will I abandon that principle because some “elected representative” says it’s O-K as long as he does it in my name.

                      When law ceases to uphold our most basic rights and instead becomes disassociated from morality and rights, it then becomes tyranny and evil…as we have seen.

                      Back to the “born 100 years ago”- Funny, but the adults who would say that when I was a kid, were so short-sighted as to think that I would come to see “how the world really works” and would “mature” and abandon that idealism in favor of practicality [i.e. go along to get along].

                      Well, either I never “matured”- or maybe they were the ones who were immature, and who didn’t have enough character to maintain the conduct and principles of what they once knew to be right; and maybe I never liked how the world operates these days, so instead of conforming to it, I reject it, and advocate for something better; and refuse to knuckle-under and just go along to get along.

                      And now thanks to the interwebz, we have found a few kindred souls who feel the same!

                    • Nunz, the film was about the open marriage lifestyle. It had Natalie Wood in it, who also happened to star in Sex and the Single Girl.

                    • Yeah, Lily was funny but she was straight.

                      I’ve noticed southern women don’t do the feminist thing and celebrate their body, men’s bodies and having a good time.

                  • That’s because to have any LEGAL involvement with one, especially marriage, puts you at odds with not only her but the almighty State, with a PRESUMPTION of wrongdoing on your part just because you’re a swinging dick.

                    Even where some aspect of romance and its logical outcome isn’t involved (i.e., marriage and child custody), you still have the weight of the so-called legal system set against you if you’re a man and your opponent is a woman…get accused of discrimination or sexual harassment, however unfounded, and you’ll know full well. Again, it’s due to a slew of self-appointed “advocates” and other busybodies and the overreach of the almighty State.

              • Shotgun and Eric feminism is a tool of cultural marxism used to divide society and destroy the family and gender roles thousands of years old. Along with depravity such as homosexuality / identity politics etc. Its obvious. The founders of cultural marxism are jews from the frankfurt school. Democrats these days are full blown communists in regards to this with a lot of republicans not far behind. This is a real interesting video – look at the first three minutes:https://www.youtube.com/watch?v=fYo1ewgG94M

        • Hi Chuck,

          You’re prolly too young to gnoe about this, but here’s a story for you in re GM and the last time there was any real recalcitrance within the company to the Safety Cult and all the rest.

          Circa 1972, Pontiac – like every other car brand – was facing a systematic assault by the federal regulatory apparat on fast cars. New emissions regs had resulted in the slashing of compression ratios across the board and limp-dick cams replacing the hot grinds that powered-up the engines in cars like the ’70-’72 Trans-Am.

          Pontiac’s senior engineers were appalled by all of this and wanted not only to maintain the TA’s performance but increase it. They proceeded to design a whole new engine – without the knowledge of GM management. This was the now-legendary SD-455. It was purposely made a 455 – so that it might pass unnoticed as Pontiac was already making 455 V8s. But the SD-455 was a completely different V8 – different block and heads and manifold … pretty much everything. The block was reinforced and had provisions for dry sump oiling. The heads were specific to the SD and featured round rather than “D” ports. It got a hot hydraulic cam and – in as -designed form – was making 310 SAE net horsepower (equivalent to at least 350 under the previous SAE “gross” standard and so stronger than the ’70 TA’s Ram Air III 400 and the ’72 TA’s 455 HO).

          The plan was for the SD-455 to be optional in the Trans-Am and the GTO.

          But that got kiboshed and the engine was only offered – in very limited numbers – as an option for the ’73 and ’74 TA and Formula Firebird. The ’74 run got left-over SD engines as the production of more of them had been ordered stopped by the higher ups.

          And that was the last time anyone at GM in a position of authority tried to give the finger to Uncle.

          • I think I remember reading that in another post of yours, actually. Wasn’t something I knew before.

            Sounds like a much lower-tech version of what Volkswagen did with their diesels.

            From a certain perspective, though, wouldn’t that have made the SD engines aftermarket poison? None of the speed parts developed to fit existing Pontiac V8s would have fit that engine, and I’m going to guess that’s probably true today as well.

            (You just reminded me that Pontiac also made 2.7L and 3.1L versions of the Iron Duke I4 for racing use; at one point I’d wanted to get one of those and put it in an old Grumman mail truck since they came with an Iron Duke from the factory, but apparently there is a difference in bell bolt pattern that makes the swap less simple than you might expect. Probably about 15 different kinds of illegal anyway, which, since it’s “emissions illegal”, means that it’s legal in practice as long as you don’t live in California or catch the attention of an overzealous federal prosecutor.)

            • Hi Chuck,

              The SD engines were part of the Pontiac V8 family tree – and so many parts did bolt on/interchange. One of the very cool things about all Pontiac V8s (except the last of them, the 4.9 liter 301) is that they are physically the same in terms of exterior dimensions; a 455 will bolt in place of a 326 – and most 326/350/400 heads will bolt right up to a 428/455 block (you just have to be careful about combustion chamber size and so on).

              The main difference between the various Pontiac V8s is internal – stroke.

              The 326/350/400 were short stroke engines; the 428/455 had longer strokes (and different crankshafts).

              Some heads had “D” ports and others “round” ports – but you could mix and match the top ends/blocks.

              And almost any intake will bolt up – so long as it’s matched to the “D” or “round” port heads!

              • And, after about 60K miles, every one of them leaves an oil spot on the driveway…but it wouldn’t be a “Heap Big Pontiac” unless it was a “Big Heap”! Back in the days when the different GM divisions were all DIFFERENT makes, and each had its own personality…and Pontiac, besides being Poor Old Negro Thinks It’s A Cadillac, was for someone whom wanted some “attitude” in their ride and were willing to spend more than for a Chevy, and weren’t become Olds or Buick and drinking Geritol just yet.

      • Back then, a turbo was ok IF you were a mechanic or he was your brother-in-law whom perpetually owed you favors to keep the damned thing in tune.

        Even dual carbs were a bitch to tune…most shops didn’t know the procedure for jack shit. You were better off to learn how yourself.

        Mopar got it right with both the Cross-Ram using dual quads on a 413 or 426 Max Wedge, and later with the 340 and 440 Six Packs…however, the “Six Pack” arrangement, for all practical purposes, is really a six barrel carburetor, and not actually much harder to tune than most four barrel jobs. However, those were all very limited run, special performance packages. Truth be known, if the engine was strong, a Carter BBD TWO BARREL did just fine for most applications. Too bad that if you use the acronym “BBD” nowadays you get sniggering.

  2. Hi Eric,

    Long time follower, first post. Interesting topic. I was a VW mechanic way back in the 1970’s and have lots of experience with aircooled cars. I even had a turbo Corvair. My first VW was a 36 horse power model and yes it was chilly in the winter in Chicago. Later models had way better heat. My Westphalia camper even had an aux gas heater. I’ve had many a/c motorcycles and never lamented that they didn’t have a radiator. I guess that makes me a luddite today. My 850 Norton still has beautiful cooling fins.

    I posted, ‘Why no Aircooled Cars’ on BITOG and some of the responses were surprising;

    • Hi Passport!

      Glad you surfaced 😉

      I often wish I had not sold my ’64 Monza coupe (110 hp, four-speed; gorgeous car and surprisingly modern-feeling in a number of ways vs. other cars of the same era).

      I have water-cooled bikes but the air-cooled ones are the lookers of the bunch. I keep thinking about a ramp system to my front door, so I can house the Kz900 and the S1250 inside the house… where else would you keep art, after all?

    • I’d like to have seen that 36 horse Bug on the Dan Ryan Expressway when it wasn’t Illinois’ longest parking lot! It’s a wonder that Jake and Elwood didn’t blow you off the road with the ’74 Dodge Royal Monaco ex-cop car (“cop motor, cop tires. cop shocks, it’s got a 440 plant, before catalytic converters, so it’ll run good on regular gas..”) as they blazed towards the Cook County Assessor’s office!

  3. Interesting to know that the long-used tank engine in US MBTs, starting with the M46 “Patton” (a re-engined version of the M26 Pershing which was rushed to the ETO in Jan 1945 to take on the vaunted Tiger tanks, it had to make do with a Ford GAA V8 engine which was adequate for the M4A3E8 “Easy Eight” Sherman that it was intended for, but as the Pershing was some 10 tons heavier than the Sherman, utterly puny. The M47, which was the same basic chassis, engine and drive train, but equipped with the turret of a MBT design that had been cancelled in favor of the Chrysler designed and built M48, as an “interim” measure to shore up US armored regiments which had been stripped of their tanks to be sent to Korea and to Germany (it was feared that the Soviets would attack), some 8500 of these M47s were produced, which was impressive for an “interim” design! The Continental AVS-1790 AIR-COOLED V12, which cranked out some 810 ponies, at least could move these beasts around, so it was also picked for the M48 Patton, as the Army wanted to stick to one fuel, gasoline, which was also commonly available from civilian stocks in Europe. There were a few problems with this approach: the engine was THIRSTY, and guzzled so much 80 octane gasoline that the effective range of the M47s and M48s was about 80 miles! But it was relatively compact and POWERFUL! The limits and fear of fire by using gasoline in a main battle tank led the Army to have Continental develop a diesel engine equivalent to the AVS-1790, so they produced the AVDS-1790, which was (conservatively) rated at 750 hp, but had more torque, and it was used in later models of the M48 and the M60. An well-known example of the air-cooled V12, of course, is used in the “Blastolene Special”, aka “Jay Leno’s Tank Car”. As Jay showed when demonstrating this beast, with all the heat that comes off the engine as the car is driven, even on a cold day a heater is simply not necessary!

  4. Another huge benefit of air cooled is that you don’t have to use a one piece block. Each cylinder can have its own jug. Meaning you can fix the rings in ONE cylinder – or fix the bearing etc… The only air cooled vehicle I currently own is a 1976 styer pusch Pinzgauer. The heat exchanger has never worked well. Very interesting engine.

  5. No problem getting plenty of reliable power from an air-cooled engine.

    Consider by way of an example, the Porsche 917 flat-12 (not a boxer, like their flat-8, this one was a 180-degree twelve). In racing trim with turbos it was capable of some 1150 bhp, possibly even more. Mark Donahue ran it like that and reported it was “a lot of fun”. Meanwhile Porsche had a “plan B” for the car. There was a flat-16 ready. It was never raced, since the turbo flat-12 was deemed (and proved to be) more than sufficient. The flat-16 with a pair of turbos was thought to be a +2000 bhp engine. Just in case.

    By the way, these were the product of Ferdinand Piech, recently deceased. In his career he was responsible for the 917, Audi Quattro, Audi 100, VR6 engine, W engine family (W8, W12 and W16, the latter of which is fitted to all the Bugatti cars). Under his management VW (more correctly it is VAG) purchased Bugatti, Lamborghini, Bentley, SEAT, Skoda, Ducati and, of course, Porsche etc. and took Audi from a minor entity to a major competitor against the likes of Mercedes and BMW. Quite an achiever, he also had time for multiple wives and mistresses (four, I think it was), producing children with all of them. He lived in a castle!

    …….and he was certainly not averse to air-cooling for ultra-powerful car engines.

    Aside from all the air-cooled radial aircraft engines, many making well over 1000 bhp, there is also Skoda and their air-cooled car and truck engines. Aside from the V-8s for the cars they had V-12s for the trucks. There were gasoline and diesel versions. Skoda also had a mighty W-18 diesel (three banks of six cylinders each). Alas these are quite rare. I bet they made a nice noise…

    There is nothing wrong with air cooling, even if you want lots and lots of power.

    • From what I’ve read over the years the main problem with air-cooled engines has been maintaining a controlled operating temperature to meet ever more stringent emission control requirements. In other words, they were “obsoleted” by government diktat.

      Speaking of Porsche, few people remember that they designed an air-cooled V6 engine (as well as a water-cooled version) for a Studebaker prototype the company built in the early 1950s – the Porsche type 542:


      • Jason, Studebaker had quad headlights on a 1966 Study that was going to be made in Canada. 10 years later GM came out with the same light setup.

      • Good read on that article Jason. I grew up in Indiana and my dad was a Study man. The last one I had was a 64 Commander that got 40 mpg around town with a straight 6 and manual tranny. Didn’t know about the collaboration with Porsche.

    • I wrote, “Aside from all the air-cooled radial aircraft engines, many making well over 1000 bhp, there is also Skoda and their air-cooled car and truck engines. Aside from the V-8s for the cars they had V-12s for the trucks. There were gasoline and diesel versions. Skoda also had a mighty W-18 diesel (three banks of six cylinders each). Alas these are quite rare. I bet they made a nice noise…”

      I made an error. It should have been Tatra.

      Sorry about the error.

  6. Good article Eric. The ‘problem’ IMHO is people allow, encourage and even ask for these Fatwas.
    The worst offenders are the corporations themselves using politics to gain market shareby punishing competitors.
    The government that gives you everything can and will take everything. The evil of climate change hoax is that so many people have been taken in by the lies.

  7. I’d like to add another explanation for the adoption of water cooled motorcycle engines and those that employ fuel injection……it allows them to charge more for their product and confines almost all repair to their licensed shops.

    • Hi James,

      Yup; it’s a form of regulatory capture – or of making lemonaid out of lemons.

      I’m not opposed to water-cooled bikes (or cars) by the way. I just wish we had the option to choose.

    • I respectfully disagree James. Yes, they are more money, but even with my EFI and water cooled bikes, which are still pretty simple minus the ECU, I still do all the repairs myself. There are many pluses and minus as described a few post below. And for dirtbikes, you still have a choice of Air or water, they are much different animals though. Depends what you want to do with them. You can still buy a DOT legal air cooled bike dual-sport bike today with a carburetor (DRZ400 comes to mind).
      Even had a time when I was taking one (EFI and water cooled) all apart cause I bent the subframe like a pretzel, and I put it all back together with a new one and it wouldn’t run. ohhh oooo. The little computer was flashing something at me, and I figured out it was telling me what was wrong. Turned out when I was plugging something back in, I accidentally bent over a tab, and it told me exactly which one. Fixed.
      Agree whole heartily with Eric though, that 20 years down the road, these bikes will not be smart to own.

  8. Eric, you answered my question: Why do most new motorcycles have water-cooled engines these days?

    I was shopping for a new bike this spring. I noticed all the new Triumphs were water-cooled, where they were mostly air-cooled two years earlier. All the Japanese bike engines were water-cooled, sans a couple of retro models and the small displacement engines. The BMW R-series is still water-cooled. The K-series isn’t. Harley has a good collection of air-cooled engines, but for how long? The new Indians were mostly water-cooled.

    Damn shame on the trend. I like my bikes air-cooled, shaft-driven with a kick-start (very rare on new street bikes: Royal Enfield and a Yamaha 400). The fewer the moving parts, the fewer the electronics, the more durable the ride.

    • Hi Joe,

      Same, ditto. Bikes aren’t yet as micromanaged as cars, but it is getting there. It was only about 15 years ago that most street bikes still had carbs and didn’t have cats or computers. Now they almost all do. Even the smaller cc bikes are injected and computer controlled. No good reason for this – just regulatory compliance, which is making bikes what cars are: Expensive, inaccessible, throw-aways.

      • I will have to chime in on this as a off-road enthusiast. For sure, all this e-stuff on bikes was for regulatory compliance, but, I think it has benefited the industry as a whole because now I can buy a DOT legal racing dirtbike. So I can just ride it from my house to the trail without loading up the truck and gear.
        I’ve been riding off-road bikes for over 20 years. Countless bikes, mostly competitive, but lots of trail riding as well and in two geographies from the Mid-Atlantic to the northern Rockies.
        I agree that carburated bikes offer the user to be able to fix them, but unfortunately, you have to fix them and adjust them all the time, even re-jetting for temp. and altitude. If you happen to be riding the rockies and are going from 2000ft EL to 5-6K that day you have to compromise your jetting and hope you don’t run too lean at 2K ft EL and smoke your bike.
        Enter fuel injected bikes about 10 years ago. Yes, we all said: but it will leave you when it breaks. We all said it. They showed up on 4 strokes first and I bought one of the first one’s in 2012. hundreds and hundreds of hours later, racing, trail riding, beating the crap out of them, 3-4 different models, and only one left me once. And it wasn’t necessarily a E-failure, it was just the fuel line from the fuel pump split, in the tank, so we couldn’t fix it on the trail. Had to push it out to the road and truck it home. Luckily in that case the road was only 500ft away. Would this suck in the Rockies if you were 10 miles from a road, YES. However, in 8+ years, only one failure related to fuel injection. We now know to carry spare fuel line and clamps. Some carry spare fuel pumps although I don’t and I have never seen a fuel pump failure (yet).
        Now, fuel injection of various forms are showing up on 2-strokes. Yes, same early complaining, and yes they are failing at slightly higher rates than there 4-stroke brethren, but the rates are very low, and I know they will work the bugs out sooner than later. I even have some re-design ideas of my own to help solve some of the early problems, but the big boys don’t listen to me, haha… Fuel injection on 2-strokes is a game changer for not having to re-jet them for temp and altitude, a biggie on 2-strokes.
        While I am one of the skeptics, my experience has been much different than I expected, and i love the fact that I can just hit the button and go, yes most racing dirtbikes have e-starters on them now, even 2-strokes. e-start was another thing that had many skeptics, but again they have changed my mind when I’m stuck on a big hill and I must hold the brakes on or cartwheel backwards. it’s a game changer when I can re-lite it with a button and not have to take my foot off the rear brake to kick it.
        Will the injection systems and e-starts break someday causing more expense than a carburetor? Probably yes., But the benefits at this point far out-way the skepticism.

        ps: for those that don’t know, a racing dirt-bike now costs $8-10K, yes a lot. But guess what, after I use and abuse them, they are still worth $5-7K cause they are in demand. small price to pay for how much enjoyment I get from the sport/pastime. You can still get a great air-cooled trail bike for $4-5K.

        Just my 2 cents.

        • Hi Chris,

          You’re right; I agree with you… but add a caveat. A carbureted bike without a computer is a generational bike. I have two that are pushing 50 years old. The same carburetors that fed them in ’75 and ’76 feed them today. They will likely be operational decades from now, assuming not outlawed and crushed.

          The FI/computer bikes – like FI/computer cars – work flawlessly (almost, usually) for about 15 years… and then they become throw-aways, due to the cost of replacing all their electronic bits and pieces, which cannot be rebuilt.

          • Eric, and I agree with you, haha…… and I don’t need to add a caveat.
            In my case, racing means staying on the edge a little. I call it pay to play. Off-road only bikes have continued to advance against my belief that they could. I think the next game changer is auto-adjusting suspension, which are starting to show up in street bikes. Can you imagine, the bike setting the compression and rebound adjustments for slow speed rock races, and increase automatically the faster you go. Today it’s a compromise how to set up your suspension: Too hard and it goes good fast but beats the crap out of you slow, opposite if you set up soft.
            Off-road racing bikes don’t have long lifespans anyway, carbureted or not. Again, the pay to play thing.
            FYI, racing off-road means thousands$ in maintenance parts per year like chains, sprockets, tires, bent and broken everything, etc……bent and broken bodies too, haha, but it keeps me younger than I am.

            You’d be happy to hear that when I heard a new 2-stroke that I wanted was going FI for ’19, even though I wasn’t $ ready, I went and got the last carbureted bike avail. and I enjoy it immensely. Is the FI bike better, yes, in almost every way, except the new FI systems are not foolproof yet, and I didn’t want a catastrophic engine failure, even though the risk is very low. If a 2-stroke FI system fails, you smoke the engine, if a 4-stroke FI system fails the bike just doesn’t run.

            • After doing a great deal of research for new shocks, I decided, costs be damned, I’d get the best I could find for my 93 Turbo Diesel 4WD Chevy. I decided on the Edelbrock IAS Performer shock. I felt like I had made the deal of my life after driving it for a while.

              They were soft and smooth(one ton, 4WD)and when you went around a curve or moved the steering wheel quickly, they’d adjust and keep the pickup flat on high speed corners and were said to be faster reacting than the electronic shock of the time.

              Unfortunately, Edelbrock sold off their shock company and now there’s nothing like them I can find. I keep my fingers crossed. If they could be made once, they can surely be made again now since the patent must have timed out by now.

        • I had a 70-something Suzuki 250 dirtbike…. All that would have been needed to make it street legal was add a headlight/tail light, speedo and turn signals…. Carbureted and no electronics….. (Guess I would’ve had to add a battery, since it was a kick-start).

          Great bike; lived that thing! Simple, sturdy, and it could fly!

          • Nunz, in 68 the 250 Zuk was the fastest bike in its category and they were damned fast. I came close to buying one but had too many irons in the automotive fire so to speak.

            Never figured out why Zuk let Kaw one up them so bad. I bought the fastest production bike made in 1980, the Zuk 1000 GS and it was so detuned stock it was one of those things made to be made faster.
            They added another gear and another 100 CC’s for 82 and that was a monster. It had a lower 1st gear than the 1000 GS and I nearly shed myself the first time I rode one and cranked it WOT in 1st gear. It wanted to stand on the rear tire.

      • Johnny, I don’t doubt it. In early 14 I constantly met a guy with one at the convenience store heading to work every morning. I spoke with him several times and he loved it. He always wore fatigues and sometimes camo with even his jacket and his old style German looking helmet. He said it was unbreakable and very comfortable. I hope he got to put one of those Mennonite girls in the sidecar now and then.

  9. I sort of inherited (he’s gone and dead, now, so get this monster out of our yard and its yours) a late 70’s GMC one tonne stepvan, 24 foot Grumman body. Engine was a Deutz air cooled five cylinder uprigh diesel. It had torque, but not much freeway power. although it was impossible to stall. Since all the cooling air was used for the engine, and there was no way to capture that easily/reliably, they had fitted a German Westhalia diesl fired heater that fired into a heat exchanger, where antifreeze cooland was circulated via an impeller pump, heated, then returned forward into the standard GM heater core and heat system, same as on the gas powered step vans. Made that part easy, but that silly heater system was quite the critter. Between that one and the identical systems I met on some boats for cabin heat, I was kept well occupied over a few years. I soon learned their foibles, and could troubleshoot them quickly. That Deutz was quite the engine, though… strong, reliable, even if gutless. I sold it to a plumbing contrator who failed to learn whether any of his guys could drive a manual gearbos.. none could. After the third clutch in two years, he offed it too. I almost wish I had that thing today. It got around 18 mpg, and for a huge breadbox that wasn’t too bad. I;ve run across the Deutz in some construction equipment, and in a small sailboat as an auxilliary, that one was a twin.

    • Tio
      What’d, someone swap that Doitz injun in there from a tractor? (I wouldn’t mind having one’a them tractors!)

      Loved those old Grumman step vans!

      “Grumman: We made vans; canoes; and spacecraft”.

      • Nunz, they made some damn good planes too. Back in the day when the EPA didn’t exist big rigs used Deutz diesels up north where the temps were much lower.

  10. Eric and TV Tech are right – as long as the ducting and sheet metal were in good shape, the bug heaters did fine. I had a 74 bug with a fantastic heater – people were stunned when I would take them to the mountains in my car because they had been in older bugs with heaters that provided almost no heat.

    And the only gas heater I saw was on a Type IV and it would blow you out of the car. Instant heat and way too hot in no time at all. I don’t think they were all that common in the US, but I’m sure they were all over Europe.

    • Hi Mark,

      Yup! I had the engine out of my ’74 SuperBeetle; after I rebuilt it, I installed the tin and ducting to factory-tight and never had any troubles keeping warm!

    • The Type 4 wagon was not uncommon in the US, I have one as a matter of fact. VW back then was usually very tight on service, they usually had their dealer mechanics very well trained and parts stocks up to snuff before introducing a changed design. Well, for some reason, they had a servicing fail with the Type 4. In the US, they only sold it with Bosch D-Jetronic EFI. The manifold pressure sensors had a design flaw that caused them to leak vacuum from a cracked brass diaphragm and other woes which confused the servicing staff. The MPS malfunction caused the EFI to go basically full-rich, thus destroying the cylinder walls and rings, etc. The car’s reputation took a huge nose dive, and the Type 4 (411 and 412) became the shortest production run of any VW car, I think even to this day. It also did not get the fuel economy expected of a VW (~22 MPG US around town) for many reasons, the biggest being the 3-speed automatic transmission almost every one was sold with in the US. Lots were parked and scrapped starting in the late 70’s. It is, however, a very nice design, comfortable, as has been said, blow-you-out-of-the-car heater. The Eberspacher gas-fired heater was standard, could be run with the engine not running (at the risk of rather rapid battery depletion!) and could be ordered with a time clock integrated with the instrument panel clock. Start your gas heater before you get to the car! It even has an electronic thermostat with a control on the instrument panel. No iPhone bluetooth remote, though.

      • I think another BIG problem with those VW Type 4’s was RUST! If you lived anywhere other than the arid states, like Arid-zona….those damn things rusted so fast it was ludicrous.

        I still remember in the 70’s in NY, when they weren’t all that old; every one of ’em I’d ever see was always perpetually parked, and just a pile of rust- even from a distance and with just a casual glance. They were just disintegrating. They looked like they were 40 or 50 years old…instead of 4-8 years old.

        That, and that that nobody knew how to service and repair the wacky fuel injection…. One’s only option was the VW dealer…and even then…..

        Didn’t they come with dual carbs at one point, instead of FI ?

        • I think it was the VW Squareback that originally came with carbs and by the late 1960s was fuel injected. (Not sure about the 411/412 and am too lazy to look it up.) Interestingly, the early Bosch electronic injection was descended from the 1950s Bendix system that AMC planned to use on the ’57 Rebel (but didn’t), and Chrysler did install on a few cars in the late 1950s. The Bendix injection system, adapted from aircraft, proved unreliable in cars and was ultimately sold off to Bosch who further developed it.


          A friend of mine bought a used 411 back when they were still common and the main thing I remember about it is that it would not start once the temperature fell below freezing due to some issue with the fuel injection that no one was ever able to sort out.

  11. Last and, in the current practicality-over-all mentality, the least, is how attractive air-cooled motorcycle engines are. Some of the most beautiful engines were the BSA A65s, the Triumph 650/750 vertical twins, the Ducati thumpers of old, the square-barrel BSA 441/500 singles, and so on. Liquid-cooled engines have all the allure of fire hydrants. And what a pain: split hoses that weld themselves to the engine, thermostats that stick open or shut, water pump bearings or seals wearing out and leaking all over, and crud plugging up the radiator’s cooling tubes.

    “The days that are no more!”

  12. I drove a VW for a couple years while I was in college in the 60’s, the “heater” was mostly a joke. You had to keep a scraper handy for scraping ice off the INSIDE of the windshield during winter.

    • Until I had an air cooled VW I used to wonder why VW drivers always had a winter hat and gloves on while driving. My 1970 Type II (van) had a gasoline powered heater.

  13. I’ve always wondered how an air-cooled engine which is powerful enough for modern driving conditions, would do in stop & go traffic (or just stopped traffic)? I tend to think they’d overheat quite easily- ‘specially if they were larger- like 5 or 6 cylinders; with the increased heat that that would generate, plus not getting cooled when going slow or stopped…. Which is likely why ya never really see ’em in anything much over a 2 cylinder configuration- except for the few, like the VW and Porsche 4’s, which were pretty low output.

    Funny though- all these greentards salivating over electric cars, which are no more efficient than the typical ICE. If they were to come to their sense and push for the elimination of all of the BS mandates so that the VW Bug (the old air-cooled ones) could be built again, that truly would be green; then maybe I’d have some respect for their whiney asses- but of course, they don’t want cars that struggle to do 60MPH and which are old-skool; they want to have their cake and eat it too- high-performance, with slick modern teckno-lodgy, and standard-equipment integral virtue signals!

      • It’s a sign of the sickness of American society today that Armistice Day, celebrating a return of peace, has been transmogrified into Veteran’s Day, celebrating WAR! Turner Classic Movies aired one movie after another glorifying killing. Peace is SO boring, is is not?

        • Amen, JDL & Eric!

          This has become a militaristic society, in which those who enslave themselves to the state to do it’s dirty-work via the use of violence against any and all whom the state declares to be “an enemy”, are worshiped by the statist majority.

          I have heard it repeated endlessly over the years, that the exploits and abuses of pigs and soldiers are the necessary evils; the price we pay to have “civilization”, “freedom” and “peace”- which of course, is just media and government school propaganda, ’cause in reality, it was the CULTURE we once had which was responsible for promoting high degrees of civilization, freedom and peace. The more we have militarized, the LESS of those things we have- to the point that those things are just about extinct….but the ranks of government and their mercenaries just keeps growing ever larger.

          This time of year, I always have to listen to this:
          Larken Rose – F*CK The Troops

        • Veteran’s Day, originally “Armistice Day”, was originally set forth to commemorate the end of the so-called “War to end all Wars”, or “Great War”, since we’d vanquished the Kaiser! Well, only 20 or so years later, along came Hitler, with a re-armed and pissed-off Germany, and the game was “on” again!

          Even Patton, by no means a peace-nik himself, denounced the foolishness of those whom said that there wouldn’t be any more wars. The very fact that the meaning of the original Armistice Day (which was meant to commemorate a victory, or at least an end to the horrific bloodshed) has been completely inverted lends credence to Patton’s saying that if we kid ourselves into believing that we won’t have another war, that in fact we WILL have one, and “Damned quick”!

    • I worked on dozens, maybe eve hundreds, of the old VeeWees. Only actuall ever owned/drove two. And both of those came on the super cheap. (how’s about fifty dollars for a 1956 36 hp beetle?), then I think I had all of fifty, maybe seventy five, into a Typ IV Karman Ghia.. no engine, cause I’d sold and installed that into another car, then took an upright 40 HP core engine, had my head mehanic redo a pair of used heads (for all of $25 the pair, including parts) slapped them on, and the whole mess dumped into the back of that Typ IV Ghia… which, being European, had much taller final drive than our Yank models. But that crazy car cruised at 80 and returned somewhere near 40 MPG.. though it took somewhere near a mile and a half to REACH that stratosphereic speed of 80 per. I wisely sold that one off to someone needing a baskc car.. by then I had discovered Volvos. They could be had for about the same money as a Bug, but would run a quarter million with nothing done but occaisonal tune ups,(valve set every 10K or so, tickle the points, ignore the pair of SU’s, and DRIVE the sucker. They would cruise all day long at 85 mph and return above 40 MPG, and have POWER for the hills, and cornered FAR better than any VeeWee but a well prepped Typ 1 Ghia. A delight to drive. And, despite being water cooled, and Eric’s claims above that such mills took forever to deliver heat into the cabin, those cars would provide noticeable heat into the cabin wihtin half a mile, even on very cold days. Whaddyaspeck, anyway, they were built for Sweden. Road trips even accross the frozen wastelands of BC’s southern interior, driving on four feet of packed snow, middle of night, if I did not have the quarter lights cracked open, and the head down to maybe half or at most 2/3, I’d think I was driving a swedish sauna and not a swedish car.
      With all that going for it, why would ANYONE put up with the quirks, shoddy constructioin, lack of reliability (any engine needing the heads off and redone every 40 to 50K is not worth owning) (and the bottom end would not last past the second pair of heads, so redo that every 100K) gutlessness, and lack of REAL reliable heat for winter…..

      Ode to air cooled? My most favourite thing about those VeeWEe air cooled cars was all the money I made keeping them running for all the crazy hippies that were dumb enough to own them.

      • My fiancé had a VW. It was a fun enough little car considering I always owned pickups. One day I drove it to town to get some parts for something else and it nearly killed me on a corner. Somehow I instinctively steered out of it but a few weeks later it went crazy on her and she rolled it off a cliff. Both survived – more or less – we rolled the Bug back on it’s wheels, added some oil, and I drove it home. So like a damn fool I bought her another one and we drove it for a little while until the engine burnt up and I swapped engines. Then a while later the front axle fell out (literally!), so I took the chassis pan from the rolled one and mated it to the body of the “new” one and put in the one good engine. We drove that a while longer but I was always fixing something on it so finally we traded it to another logger for logs that I hauled and sold.

        I can’t remember now if I got the heater working right or not, but I spent hours working on the ducting while I had the body off of it, which was about the only way you could really do some of that. Before that I remember scraping ice off the inside of the windshield as we drove.

        • No matter what, it seems with the old Beetles that if you had honest-to-Gawd wintry weather, you were scraping the windshield on those freezing mornings. I recall that my folks had a ’60 Beetle, and once Dad got his orders to go to Andrews AFB (near DC), Mom got a new ’68 Chevy Bel Air wagon (327 small-bloc, 4 barrel Rochester, a metallic green battleship to drive around the tribe), and Dad commuted and putted about with the Bug. That old VW was fun! He’d practice, when he took myself and my older sis out, the ‘dead stick landing (coasting down a fairly long hill with the engine off and making it into the driveway), and if you were travelling in the clockwise direction of the Beltway down towards the Potomac, a rather long grade as you headed for the bridge, you could get that thing up to 75 mph, and if you had a headwind (which might limit the top speed to 70), you could do a ‘wheelie’! But the best part was those cold winter mornings, where Dad would fire up the Beetle, and the engine by then being just a bit tired, need a few minutes to warm up before the car would actually move with some ‘alacrity’. So, having packed a thermos of coffee for the day at the office, he’d set the last cup from the pot (either Folgers or Maxwell House, always black) on the roof of the Bug and proceed to scrape the windshield and windows free of ice. Well, sometimes he’d forget about his coffee cup, and when he got home, there was a frozen cup of coffee stuck to the roof, having made the trip (about 3 miles) to Andrews and back.

    • Nunz;
      Air cooled’s such as a VW will start to cool down in traffic or idling. My ’65 Bug has a 2 liter engine making close to 120hp and runs cooler and gets better mpg than a stocker, providing I keep my foot out of it (the mpg part, which is quite difficult to do, it’s just too much fun!) I have it geared to take advantage of the torque and HP it makes to be able to cruise all day at 75mph. A stock Bug well tuned will run about 350f on the head temps, mine runs around 225f, even in 100 degree weather! As long as there is air blowing over the engine, it will cool (providing all the tins and thermostat are present) Too much rpm will cook the oil, not enough rpm will cook the heads. It’s all in the “combo”.

  14. BMW motorcycles had air/oil cooled GS and other engines till around 2013? Then they went water cooled. I think this year they had to go to an adjustable valve timing setup as well for emission standards.
    Single cylinder dirt bikes are still avail. air cooled for non-competitive trail bikes, but the racing versions went water cooled I think in the late 70’s, not because of emissions, cause they didn’t have to meet them, but for performance. I am not aware of any DOT legal street bikes that still come in air/oil cooled only.
    These ever increasing emmission standards for very small percentage games are hurting all of us, a lot.

    • update: how stupid am I, Harley’s are mostly air cooled still. There are obviously others, I just can’t think of them at the moment.

    • Yamaha XT250 is air/oil cooled. Many other small CC bikes, DOT complaint and street legal, are still available. Some large Ducati twins still available as well (Scrambler). Some scooters are still air cooled. But you’re right. It’s only a matter of time. Buy one while you can.

      • Yes, sorry. I was stuck on street bikes, but there are a lot of small trail bikes still air-cooled and I think they will remain for a long time. I hope so anyway.

    • Depends on which engine you’re talking about. VW Type 1 and 4 engines (Beetle, Transporter, Type 3, 411/412) used heat exchangers around the exhaust downpipes exiting the cylinder heads. Air was blown through the heat exchangers by the engine cooling fan, or the fan boosted by a separate electrically driven blower (Type 2 and 411/412 only AFAIK). All of them depended on having all the tinwork and ducts/paper hoses leak-free to get the air into the cabin, and that was usually the problem. The Corvair started life with only an auxiliary gas-fired heater, then transitioned to a system like VW’s around 1961. The optional VW gas fired heaters were brutes, they could keep the insides so hot they had a thermostat to throttle ’em back!

      • So not nearly as advanced as the old East German Trabbant which had a kerosene heater.
        (But only for senior party members, not up and comers like Fraulein Merkel.)

        • The “senior” KPD members and the otherwise “connected” drove the better Volgas, or even a few Russian-made Zughli limosines, or some of the Czech-made Tatra models, or, with a few (wink, wink!) bribes and looking-the-other-way, a West German Benz that somehow was “left” there…anything BUT a “Trabbi”!

          Interesting that these once-derided shining examples of Marxist-Leninist automotive technology have made a sort of comeback as a collector’s item.


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