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CRF250l Wiseco Higher Compression Piston

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Has anyone used the Wiseco 11.5-1 stock bore piston in the 250L?  If so can a difference be noticed and did you add the ejk to it if stock?  Was wondering if it was worth the $400, still a cheap MOD tho since Wiseco says you can just drop it in and go.  My bike is still stock and figured it couldn't hurt, especially seeing if it will take care of that annoying chattering/tapping sound the motor makes between 5000 and 6000 rpms.  Noticed the majority of 250L owners and CBR 250 owners complain about it.  Couldn't find a thread on the pistons so if you know of one lead me to it please.

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I think if a guy also had some head porting and maybe valves and cams and flow benched then tuning on a dyno and having an EJK installed you could get some pretty good gains and maybe last longer than the 305BB ....  :thinking:  I am just not sure how much gains just adding a piston would net with a EJK. The noise you mention is cam chain noise. 

 

Hard to say tho .... my 305 is running pretty strong these days and combined with the clutch upgrade running 13/44's I can easily clutch up 3rd gear wheelies and have not really thought of trying to clutch up 4th. It might take more effort and better timing ... we'll see the next time I get to ride. We have lots of rain in the forcast. 

Edited by gnath9
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Thanks for the info.  Mines a 2016 and you would think by now Honda would have fixed it but I have seen where the legal department at Honda says it's normal sound for the motor and wasn't anything to worry about.  My goal with the bike is add ejk, exhaust and K&N, but thought raising the compression just a tad bit with same bore size would indeed last a whole lot longer than big bore. Wiseco even makes a 283 or something like that but not interested in boring out.  I can power up first gear with 13/42 but would really like to power up second.  I really think on pavement it will with the 3-5 HP gain of full system. I have seen via YouTube that the main kink in the hose is the header. Plus I've seen a lot of long term issues with both brands of 305.  I've seen a lot of people say "you should've bought a different bike instead of trying to turn yours into something else.". #1 I'm no Ryan Villopoto and will never ride the 250L at full potential #2 you have $1500 of parts you can put on it before the price of WR #3 I can't jump on the highway with a R model.  However, I do enjoy toting the front tire and if I can get this sucker to power up 2ND it will be the perfect bike for me. I know the higher compression will make more power but I don't want to make it too much for the OEM clutch even tho I have a mad scientist mechanic who is a genius which is hard to come by, especially one you trust. No offense to anyone who is one on here but I sold parts for Harley Davidson at one time and know how shops can really get ya.

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 I lost some low end compression after installing stage 2 cams. The 11.5.1 did seem to help though. I remember another tt member trying it and liked it but not a drastic change. Since then got some head work done and dyno at 24.6. Was hoping to get 26hp

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I had to go to a 1 over piston and could not find a OEM one, so have over 10 k km on my wiseco. Runs great, as it always did, did not dyno it, but seems as peppy as always, and onlu cost $115 on ebay

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