SOHC.co.uk Forums > The Black Bomber Board

Bits of metal found near inlet valve

<< < (8/8)

K2-K6:
Interesting Ash, about the teeth. They usually wear generally if given a chain pitch out of ideal tolerance.  Suggesting that the culprit us primarily of cam chain lubrication.

It would be interesting to see the original chain on this one, wrapped around one of the sprockets, then the opposite side from the two ends pulled up to assess for wear.

The design of these looks to be marginal in that later designs (750 as example) move to more curved guide rails, ultimately this mitigates chain "twang" which can be significant contribution in cam drive arrangements.  Reducing noise too.

nairb:

--- Quote from: K2-K6 on December 02, 2025, 08:39:22 AM ---Do you have more detail in photos of the failed parts ?

--- End quote ---
Here are 3 more pics.  Nothing rotates or turns.  It all seems seized up.
[ Guests cannot view attachments ]

no 2
[ Guests cannot view attachments ]

and finally
[ Guests cannot view attachments ]

Still not replaced the wheel yet.... Do I drill or unscrew the centre part.

It gives the impression of lubrication failure.  But all the other wheels seem fine.
I have cleaned out the centrifugal oil filter.  It was not too bad.  Maybe I will simply re-build the top end.  I think it was factory finished and not been apart.
I did mean to add that a brand new did chain will be fitted.  I have not checked the old one.  At 12.k miles on the engine, I think it should still be service-able..... But I should check

 

AshimotoK0:



[ Guests cannot view attachments ]

Navigation

[0] Message Index

[*] Previous page