The Teardown Begins!

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I’ve begun the process of disassembling my recently acquired 1974 Kawasaki S1 Triple and this is the first of what will hopefully be a running photographic and commentary account of the rebuild/restoration.

First, the starting point:

This is the bike “as rescued” from its tomb – the barn of a good friend. The bike is not running but it is complete – it even still has its factory spare spark plug case and (much more important) the complete factory air cleaner with the three individual rubber boots that go to the carbs. These are hard to find – and expensive if you do find them. Other cool stuff: There’s an original dealer sticker from the early ’70s that I’m going to try to preserve – and check out the plate with 1985 registration decal!

The bike is worn out, but not a wreck. The wiring harness has not been cut and spliced; the engine turns freely and only has about 9,700 miles on it – so probably all it will need, aside from a good cleaning on the outside, are new piston rings and crank seals on the inside. My friend Graves, who knows these two-strokes better than I, says the crank seals are the single most important Thing to Do on an old two stroke. It’s also the one fairly complicated and somewhat expensive thing, as the crank must be taken apart by someone who has the right tools and knows the job. I plan to farm this one aspect of the rebuild out – but everything else I will be doing myself.

Here is a picture of some of the top-end stuff: The carburetors are a little funky – if you’ve never fooled with two-stroke triples before. Each has its own throttle cable and choke cable, for openers. I will boil the carbs – rather than dip the carbs – to do the initial pre-rebuild cleaning). This is a safe way to clean old carbs without using caustic solvents that may damage delicate (and hard to replace) parts.


I also boiled the cylinder heads (there are three, one for each cylinder). These won’t need any machine work; just degreasing followed by a nice coat of high-heat aluminum paint to restore the brand-new factory look.

The header pipes are in amazingly nice shape; once I got the grease off, the chrome looked almost good enough to just bolt ’em back on once the engine’s ready. But I will be sending them off to be rechromed. The rest of the stock exhaust system – even the clamp-together connectors that tie the header pipes to the mufflers – just needs a clean-up. I lucked out here, because a repro/NOS S1 exhaust can cost big bucks.

Here is a picture of the engine, just before I pulled it out of the frame. As you can see, the heads are off, as are the external covers for the generator/points and oil pump. I’ve wetted down the cylinders with WD-40 and can feel no ridges or scuffs on the cylinder walls. Assuming everything checks out – and I think it will – I will just clean the pistons and refit them with new rings. I doubt new pistons/overbore will be needed – a big money saver!


And here it is, out of the frame and ready to ascend to my workbench for tear-down. Once I have the cases open, the crank will be making a trip to my friend Tim Marchon, ace mechanic and two-stroke dirt-bike racer. He will do the seals. While that’s in process, the cylinder jugs, oil lines/pump and other internals will be cleaned up and fixed up as necessary. The cases will be degreased, then polished. I prefer the polished look over the chromed look. I like chrome as an accent – and anyhow, I want to bring this S1 back as close to “factory” as I can.

Here’s another, closer-up view of the S1’s heart:


So far, everything is going very smoothly. I haven’t had a single bolt snap (or refuse to turn). One reason why may be that I’m taking it very slow and easy. I soak down every fastener with PB Blaster (this stuff is the ticket, by the way) and let it sit overnight before even attempting to turn it out.

Another thing I’m doing – and always do when tearing a bike (or car) down into its bits and pieces – is to carefully, precisely and thoroughly document what went where and keep it all organized. All fasteners (for example , the engine-to-frame mounts) are first cleaned, then tagged and bagged. Each bolt is numbered, with the number corresponding to a hand-drawn diagram of the assembly, the number showing on the diagram where the bolt went. If you have never done a teardown before, please – listen to the Voice of Experience and do this. You will not – cannot – remember what went where, especially months down the road, when you’re trying to put it all back together. A little bit of cataloging today will make your life – and your project – much easier. Trust me. Please!

O k, that’s it for this installment. Look for Part II soon!

Throw it in the Woods?



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