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Discussion Starter #1 (Edited by Moderator)
Hi! I was so tired of leaks in my beautiful Triumph America.

Decided to kick-off a reform project to redesign and manufacture a set of new Camshaft holder caps, which are the main issue for leaking Triumph twins.

Made of HQ aluminium. There is a set of 10+ pieces to be sold to cover my design, material & CNC-costs. Hoping this will solve the issue with other Bonnie riders as well.

EDIT: Link removed.

Best regards,

Jari (Finland)
 

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Top caps are not interchangeable between our motorcycles. The head is bored with the caps in place when the head is assembled. No two are exactly the same. You can't just buy a replacement off of eBay.

And not all the caps are the same shape anyways.

That part number in the listing is for sure entire head. If you look it up you'll note that caps aren't sold separately, for the reason above.

Can anyone with experience building these motors tell me this isn't simply a scam?
 

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As previously noted by Bonnie Black above.
Cam shaft bores as well as crank shaft bores are all line bored with factory caps in situ.
They cannot be replaced with out having the assembly re-line bored with all caps in place. Further, you would need to skim cut the head to reduce the effective inside diameter to allow for the new inside diameter to be bored back to factory size OR an oversized bearing would be needed.
You may be able to hone them to OEM size IF the replacement part was specifically made with a reduced inside diameter BUT the hone stones will favour away from the excess material potentially resulting in an oblong bore shape hence the need for single point rough boring prior to finish honing.

not something this ticketed automotive machinist or the matching CNC machinist ticket sitting next to it would recommend.
 

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Camshaft caps "are the main issue for leaking Triumph twins"??? Seriously???

Leaks of what? And where?
 

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@Back2-2 deleted it,

I really wanted to know if I was wrong about these caps not being interchangeable. And if they're not, wanted everyone to know that.
you are 100% correct.
it sucks to think some unfortunate eBay shopper may ruin they’re perfectly fine engine by attempting to install these to fix some “internet” problem.
I agree with leaving the posts up as an information source or warning.
Owen
 
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