Author Topic: Cylinder stud 'tall o-rings' -- too small?  (Read 481 times)

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Offline drumstyx

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Cylinder stud 'tall o-rings' -- too small?
« on: January 04, 2017, 02:24:04 pm »
I got the gasket set from cyclex for my '78 750K, and it included those tall o-ring packing things that go in the cylinders to seal the oil passages (12115-300-000), but they seem a good bit smaller than the originals, they wiggle around in there quite a bit.

1: Are these ok to use? I'd assume not, because if I'm going to all this effort, it might as well fit right

2: Can I reuse the old ones if they're in good shape? They seem to be...nearly as flexible as the new ones even.

3: If not, where can I get these? They're extremely expensive from Honda it seems...something like $7/piece USD, probably something like $10-12 each in Canada.

Offline flybox1

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Re: Cylinder stud 'tall o-rings' -- too small?
« Reply #1 on: January 04, 2017, 02:51:37 pm »
They are not needed.
I omitted them in my build without issue.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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Offline drumstyx

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Re: Cylinder stud 'tall o-rings' -- too small?
« Reply #2 on: January 04, 2017, 04:56:00 pm »
On closer inspection...Are these just return passages? If so I'll probably just use the old packing, since it seems the only fiction they could reasonably perform is preventing return oil from getting near the cylinders. Even then, there's plenty of gasket there to deal with it...