250-500cc Another Piston Thread

Paul D, engine looks awesome.

I rode out of AC campground a few weekends ago. Did you do that one?

Yup I was there. That was a great ride. I was wondering if you were there. Once your up and running we should meet up for a ride. I mainly run singletrac at a mellow pace.
Let me know if you want a hand measuring your piston and cyl as I have a set of micrometers and a dial bore guage.
Good luck with your project

Thanks. I bought all the parts already and am just waiting for them to come in next week.

That was a ton of single track. I was shot afterwards.

I FINALLY order my parts, but I went OEM from Hall's. After talking with the shop doing the Nikasil plating, www.powersealusa.com , Power Seal and following their suggestion I went with OEM parts and staying with the "A" size my cylinder currently is.


Mike Bru and PaulD, You guys breaking the "Fight club" rules?!!?!?

No way! I was brief!

Woo-hoo!!! I'm making blue smoke again! She fired on 3rd kick. Let it idle for two 5 minute sessions. Sounds real good. Topped off coolant ready to go put around the woods easy for a while. Lots of Damn snow in the trails tho. Gonna run a full tank easy at 32:1 before letting her rip

Nice. My Wiseco stuff is back ordered until 2/20, as of now. Ordered a week ago.

Where did you order it from? I like to search for the part number then look for the same part at Amazon.com and they all ways have fast shipping and usually the best prices.

I used mrmotocross_parts off of eBay. When I ordered it said they had 2 in stock. Then told me inventory wasn't updated fast enough with walk in customers. Whatever. I'll wait it out since I wont be riding until March anyway.

I'm expecting to get the call from www.powersealusa.com in the few days telling me the cylinder replateing is complete so I can reassemble my motor...

So while I'm waiting for the piston kit to arrive later this month I opened the Athena gasket kit. It has 2 identically shaped base gaskets (name correct?), one thicker than the other.

Do I just measure the existing one and match it?

I'm not looking to change power characteristics or anything like that. Thanks.

Mike I ran into the same issue. The thicker of the two measured exactly the same as my old one so I went with it. Was gonna do the squish measurement but didn't have the correct adapter for my dial indicator. It is running great. Don't hear any pinging or knocking.

Thanks, I'll do the same.

15 degree high with a lot of wind chill in NJ this weekend. Even if it was together, I'm not going to lie, I'd be inside!

Ha i used the thicker one too only because i have had the head machined so squish is @ 55 thou.

so what is the recommended squish for these motors?

Think it was around 110 thou like over 2mm wich is where the squish is doing nothing!
Hence me getting mine to actually do what its supposed to.

So the Wiseco piston is now back ordered until 3/1. Was 2/20. Who knows if it will be extended again.

RMATV has this Vertex. I also have the $25 gift card from Dirt Bike mag burning a hole in my pocket.
https://www.rockymountainatvmc.com/p/3245/32254/Vertex-Piston-Kit-Standard?v=9986

Will this Vertex work in my C size cylinder without any issues?

Thanks
Mike