Identify piston size by numbers

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Apr 18, 2018 | 08:33 PM

Jlait1982

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Weekend Warrior

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Identify piston size by numbers

have a piston that came out of an 86 polaris trail boss 250 it has the W stamp under it which tells me it is a Wiseco but then numbers on top are A6717 or maybe the 1 is an I. Can’t really tell. Anyways can anyone tell me what this piston is?

Apr 18, 2018 | 11:22 PM

user493

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From: Michigan

The 5 pistons they make for it are part numbers 536M07200, 536M07250, 536M07300, 536M07350, and 536M07400. The last 4 numbers are the diameters from 72.00mm-74.00mm. 72.00mm is stock.

Apr 19, 2018 | 01:53 PM

Jlait1982

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<div style="text-align:left;">But this one does not have those numbers on it only the ones I stated </div>

Apr 19, 2018 | 05:24 PM

user493

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From: Michigan

I searched for A6717 and A67I7 and couldn't find anything for either number.

Apr 19, 2018 | 08:28 PM

polman500

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You have to measure it...Or...might try contact Wiesco and ask them?

Apr 20, 2018 | 09:24 AM

old polaris tech

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From: North Texas

If you had a W on the piston U took out,probably a Polaris cast piston. Stock piston had just the W mark. Oversizes had the .25 or .50 on the opposite side. May be rubbed off. Really doen't matter what piston U have in it, just have to measure the cylinder for the over size size Wiseco that will clean up the bore.

Apr 20, 2018 | 02:54 PM

user493

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From: Michigan

That explains it. I've been wondering if the W mark actually meant is was made by Wiseco, and if it was, why the number didn't match anything they make.