Author Topic: 836cc forged piston to bore clearance  (Read 1952 times)

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Offline Davez134

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836cc forged piston to bore clearance
« on: November 13, 2014, 02:42:45 PM »
I've read a couple of posts about the clearance of Wiseco 836cc forged piston to bore clearance. I'm planning on dropping cylinders off next week to my machine shop and just would appreciate any personal experiences and opinions. Box states ".0020" clearance, which seems great, then I get to researching/over analyzing and driving myself nuts! I read a few posts from hondaman (and have his book) referencing .0022 to.0024 clearance, then Big Jay from APE, who obviously is very familiar with these Pistons referencing .0015 to. 0020 max. Bike will have webcam41, already stage2 ported head by JMR, ridden often, not raced in Las Vegas where it gets quite hot. I am not an experienced builder, but I am trying to learn. I basically understand the "why" of the clearances, different materials heating/ cooling at different rates, oiling, heat transfer. Looking for some personal experiences and suggestions. Thanks for taking the time!

Offline 754

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Re: 836cc forged piston to bore clearance
« Reply #1 on: November 13, 2014, 07:24:21 PM »
How old is the kit?.. They used to run 2 1/2 thou or more, now they run a lot less.. Depends on the alloy of the pistons.
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Offline Davez134

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Re: 836cc forged piston to bore clearance
« Reply #2 on: November 13, 2014, 07:43:14 PM »
How old is the kit?.. They used to run 2 1/2 thou or more, now they run a lot less.. Depends on the alloy of the pistons.
Brand new kit. pics of the pistons here:
http://forums.sohc4.net/index.php?topic=139768.msg1622252#msg1622252

Offline BPellerine

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Re: 836cc forged piston to bore clearance
« Reply #3 on: November 14, 2014, 12:42:05 PM »
read somewhere that m reick likes the weiscos for their reduced clearance ,you might send a pm to him.bill
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Offline calj737

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Re: 836cc forged piston to bore clearance
« Reply #4 on: November 14, 2014, 01:45:14 PM »
My Wiseco pistons also list .0020 for clearance. I followed it to the letter, so to speak.
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Offline Davez134

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Re: 836cc forged piston to bore clearance
« Reply #5 on: November 14, 2014, 07:07:34 PM »
read somewhere that m reick likes the weiscos for their reduced clearance ,you might send a pm to him.bill
Ok thanks. He did my head work and said those pistons would work well for me. Will hit him up on his experiences with them.

Offline Big Jay

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Re: 836cc forged piston to bore clearance
« Reply #6 on: November 16, 2014, 06:43:38 PM »
.0015 to .002"

Offline Davez134

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Re: 836cc forged piston to bore clearance
« Reply #7 on: November 17, 2014, 05:36:39 PM »
Thanks! Dropping off tomorrow