26 June 2014

I rode it, it rattled. The project IT175D SAGA!

Here is probably the penultimate thrilling instalment...

Jerry Rulf

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Yes, and “saga” is one of two Icelandic words commonly used in English - do you know what the other one is? Geyser. It's all them like volcanoes and all that what they've got..

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I rode it, it rattled - more of a clicking really, it sounded to me like a small end or gudgeon pin, so I took the top end off. A bit of necessary investigative surgery if you like. Happily, as on the rest of the bike, all nuts came undone easily, thanks to dry USA air. This is a lovely view down the exhaust port, all looks ok so far except the remains of rust corrosion on the bore (right hand side of pic if you can see it).


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Copper head gasket was re-used after annealing. Unusually, these and DT models don't use through studs, but separate studs for the head and barrel.


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Head looks unmarked, suggesting it hasn't been run without air filter, which is good.


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Tapped the barrel (it's located with dowels) and slid it off to reveal a piston that has more scars than a Prussian aristocrat. It looks tired and damaged (like all of us) but not like it's had a bad seizure.


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Same on this side. Yuk!


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The gudgeon pin was tight, so I improvised a puller/pusher with a 2 legged puller, a bit of metal, a big nut and a rag- it worked fine, and the suspect small end turned out to be ok, but for a couple of quid it seemed prudent to assemble it with a new little end bearing from Wemoto.


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This is the matching damage in the bore- as there is rust, I think it might be from turning it over/running it after being stood idle for years, and the fine corrosion shown here has smeared into the piston. Not having time (or the dough) for a rebore and piston, I rubbed the bore down with very fine abrasive paper and took out the rust and marks- I did it at roughly 45 degree crosshatch pattern as in the original honing pattern. Cleaned bore thoroughly! Don't want to leave any abrasive in there...


All re-assembled, started fine, ran fine- but still clicked! I now think it must be the piston/bore making the noise, something to sort out later if feel it's necessary.

So it's nearly there, just a few minor details like the MOT! Watch this space for how the IT gets on with that.

Any comments? Email: [email protected]

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