CR Need a new top end?

Bic

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Aug 12, 2007
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#1
My 2003 CR250 does not have steady roll on throttle. It takes a while to "catch" and start to pull. When you give it throttle in first it basically Bogs, whomp whomp vroom. Its not steady at all. I had the carbs cleaned and a new plug which helped a considerable amount but it is still doing it. The tech who cleaned my carb said he pulled off the exhaust and said it looks like the piston and rings are worn, but he wasnt positive and was going to charge me an arm and leg to take it apart to give me an estimate. Could this be the problem? Any suggestions? I use high test octane and run 32:1 with HP2. Please help, thanks! :whoa:
 

Backslayer

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#2
You should check your compression on the piston but it sounds to me like your jetting is off
 
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#3
might sound a little stupid but have you checked your chain?? Is it loose??? It might be the reason... Just a suggestion. Otherwise yeah what backslayer said
 

Bic

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#5
I had another tech test my compression and he said it was fine. Would a worn top end cause this to happen? Once it gets past the hestitation at a little higher RPM it runs fine. Like i said it was a lot worse before the carbs were cleaned. Also, whats a power valve, i thought that was on 4 strokes?
 

IndyMX

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#6
If you have good compression, the top end isn't worn.

Either your jetting is wrong (too rich) or your Powervalve is stuck open..

Get a service manual. 4 Strokes have intake & exhaust valves, 2 strokes have Power Valves... Honda generally calls them RC Valves.