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Yamiya CB750K0 Fork stanchions

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AshimotoK0:
Anyone used Yamiya early 750 stanchions? I fitted mine but noticed the bottom piston and valve ring was sloppy fit on the stanchions.

The attached pic  is what I found when I measured them.

 Going to take this up with Yamiya but they are hard to get a reply from  as far as I know and I bought them a couple of years ago via Saisei

Opposite to DS ones as his are chromed at the bottom and parts don't fit on

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UK Pete:
Do you think it's enough to make any operational difference once  assembled and on bike

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AshimotoK0:

--- Quote from: UK Pete on September 25, 2018, 05:34:38 AM ---Do you think it's enough to make any operational difference once  assembled and on bike

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--- End quote ---

I am not sure Pete but the clearance between the  the bottom piston to the alloy fork bottom wall is definitely critical so any play between the stanchion and the inner wall of that piston should also be significant as far as I can tell.  Also how is 0.2 mm extra clearance  going to affect the  operation of the damper valve ring?

I have emailed Yamiya but so far no response. If I get no joy from them,I am not sure if someone could hard chrome just the bottom section and grind to correct size. Another other option would be  to have damper rings and bottom pistons manufactured with undersized bores. Only other more bodgy method may be to Loctite some 0.1mm  shim to the stanchions to take up the extra clearance. I also noticed that the very  bottom circlip was mighty difficult to get onto the stanchion but conversely,the piston/damper ring retaining clips were a looser fit than the originals .

Why the hell can't these people faithfully reproduce the original Honda parts ?  So we have DS selling them that are oversize and Yamiya selling them undersize. To be honest I would have preferred them to be oversize so that I could have machined them.  Should have taken Triggers advice and sent my originals to Phillpots for hard chroming but my old ones were VERY heavily pitted at the bottom yoke clamping region and I assumed the Made in Japan ones would have been spot on correct.

UK Pete:
I here what your saying ash , it's beyond belief in this day and age of manufacturing tolerances how F-ing hard can it be
I don't think silver's sells them anymore
Lots of originals have very deep pitting and corrosion which is beyond repair so we are having to overcome this bloody problem


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AshimotoK0:
I have just messaged Philpots to see if they can selectively build up the undersized area and grind back  to correct size.

My Man-in-Japan's wife is Japanese so if I don't get any joy I can probably ask her to speak to Yamiya  directly on my behalf. I can't believe that this has not be talked about before ... unless mine were just a single wrongly machined set....I find that hard to believe though.

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