Jump to content
Sign in to follow this  

2001 YZ426 Cylinder Markings

Recommended Posts

Hey, I am redoing my top end and found these markings in the cylinder.

Does anyone know what the mean?

I just installed a standard size piston on a little worn cylinder.

I haven't run it yet.

1448388447290.jpg

1448388463131.jpg

Share this post


Link to post
Share on other sites

They don't mean anything to anyone outside the factory.

 

There is only one size piston available from Yamaha because the bore cannot be resized.  When you imagine the cylinder wearing to a larger size, bear two things in mind: The most it is allowed to wear before it needs to be replated or replaced is .002", and the wear only happens in part of the bore.  If you put a larger piston in to fit the loose part, it would be too big for the rest of the bore. 

  • Like 1

Share this post


Link to post
Share on other sites

They don't mean anything to anyone outside the factory.

There is only one size piston available from Yamaha because the bore cannot be resized. When you imagine the cylinder wearing to a larger size, bear two things in mind: The most it is allowed to wear before it needs to be replated or replaced is .002", and the wear only happens in part of the bore. If you put a larger piston in to fit the loose part, it would be too big for the rest of the bore.

Thanks for the info Gray.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×
×
  • Create New...