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cr250 single ring?
Posted: July 28th, 2010, 10:15 pm
by M.F.D.B.
Any of you MX guys running a late model cr250 with a single ringer? What kind of life times you getting?
Posted: July 28th, 2010, 11:52 pm
by 100hp honda
get oem. thats what i used in mine before it sold and ran tits. normally i wouldnt use that kind of piston but i made a exception

. probly still got a used one laying around. might be in good shape if you need it.
Posted: July 29th, 2010, 2:22 am
by 2strokeforever
i bought oem for my 02 cr 125 because i could hear piston slap and i wish i didnt go with oem i had a A cylinder so i got a A piston and
IT CAME WITH 7 THOUSANDS OF AN INCH CLEARANCE AT THE TIGHTEST POINT WTF its suposed to have 1.5-3
so if you go with oem for any late model honda smoker make sure it has the proper clearance before installing it
later i ended up putting a 02 RM 125 pro x piston in that bike with 2.25 thou
no more piston slap, and the wrist pin was 1.5mm lower which lowered the port timing a bit, gained a lot low mid and i didnt notice any loss in the top
it wasnt just 1 piston because i had 3 oem pistons, 2 new and all were out of spec before they were even installed
no the cylinder was not worn... i measured it
Posted: July 29th, 2010, 5:43 am
by Roostius_Maximus
i always run namura pistons in our 02+03 250s, Chad that i do alot of work for runs a single ring on his 500s, on wisecos or oem, plated or cast liner. Just prepping a pair of RC pistons for a nik'd cast liner 500 for him.

Posted: July 29th, 2010, 8:02 am
by M.F.D.B.
No OEM for me they had a lot of problems with cracking skirts. And this motor is super low hours and already has tons of blow by. Its going forged all the way for me. I run this bike MX only so im more worried about performance than getting 3-5 years between top ends like my 500.
One thing I dont want is a blown motor half way up the face of a huge jump like the one that killed a riding buddy of mine recently...
Posted: July 30th, 2010, 9:54 pm
by 2strokeforever
No OEM for me they had a lot of problems with cracking skirts. And this motor is super low hours and already has tons of blow by
$5 says all the problems are because the piston has way too much clearance
prox works good because you choose the size down to 1 thousands of an inch, and its oem kinda
whatever you get make sure it fits properly
Posted: July 31st, 2010, 12:09 am
by asteroid500
Like "ALL" high performance parts there shelf life is "ALOT" shorter then a generic or standard part.
Hell my owners manual on my 250, say's to change the OEM piston & rings every 8 hrs...yeh righty ho.
Posted: July 31st, 2010, 12:30 am
by M.F.D.B.
Yeah if I followed that BS in the manual id be doing a piston every other weekend. The reason i was asking is 05+ bikes came stock with a single ringer...
Im considering sending this jug off to Eric Gore for a port and race gas squish so ill prolly do the single ringer at the same time...
Posted: July 31st, 2010, 4:03 am
by Tharrell
I just put a new topend on mine a couple of weeks ago. I'm interested in hearing more after you get it back.
Posted: July 31st, 2010, 6:50 am
by asteroid500
if you race & find yourself up the pointy end often, with a good maintanance schedule then do it......if your a social rider then i'd go for the double ringer for longevity & reliability....IMOP
Posted: July 31st, 2010, 1:30 pm
by M.F.D.B.
I dont race yet as I dont feel my cardio is up to it. But a few of my buddies have been pressuring me to do some GP's with them so it may be in the near future...