Vertex piston clearance?

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bjacobsen
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Vertex piston clearance?

#1 Post by bjacobsen » Fri Dec 29, 2017 3:02 pm

I’m getting ready to have my cylinders bored to a new set of vertex pistons (cast) and I’m wondering which piston clearance I should use as the vertex differs from the oe recommendation. Vertex recommendation is .0019” to .0023” and oe recommends .0024”-.0026”. My inclination is to use the middle of Vertex’s recommendation and go with .0021”. Any of the engine guru’s here have any reason to do somthing different? These are 3rd over 64.75mm.
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Brett

hondaror
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Re: Vertex piston clearance?

#2 Post by hondaror » Sat Dec 30, 2017 4:58 am

With stock cast Pistons, I used to run 0.003" clearance, which according to Yamaha was a worn spec. Those Pistons are no longer available from Yamaha.

Follow the manufacturer of the Pistons specs. Always. Newer Pistons have newer properties, and are made with newer technology.

In the end, proper warm up will help reduce wear and problems.
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T.RexRacing
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Re: Vertex piston clearance?

#3 Post by T.RexRacing » Sat Dec 30, 2017 9:37 am

Always use manufacturers clearances. Unless experience shows you otherwise.
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evan_calgary
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Re: Vertex piston clearance?

#4 Post by evan_calgary » Sun Dec 31, 2017 5:31 am

middle of range is way to go as well.

bjacobsen
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Re: Vertex piston clearance?

#5 Post by bjacobsen » Tue Jan 02, 2018 4:07 am

Thanks, going with .0021"

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JanBros
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Re: Vertex piston clearance?

#6 Post by JanBros » Thu Jan 04, 2018 4:26 pm

with the new Wiseco's, you no longer have to worry about that ;-)

http://blog.wiseco.com/one-size-fits-al ... ke-pistons" onclick="window.open(this.href);return false;
if it runs, you can race it !

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Re: Vertex piston clearance?

#7 Post by Palolo » Thu Jan 04, 2018 5:08 pm

JanBros wrote:with the new Wiseco's, you no longer have to worry about that ;-)

http://blog.wiseco.com/one-size-fits-al ... ke-pistons" onclick="window.open(this.href);return false;
That's interesting info about Wiseco. Maybe their new pistons are as good as or better than Wossner. I found the application chart, it did not include our favorite bikes (RZ's, RD's, Kawasaki triples).

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Re: Vertex piston clearance?

#8 Post by waltmil » Fri Jan 05, 2018 6:02 am

Sounds like those are meant for plated cylinders.
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