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Idle, cranking, & compression release questions on 08 450x

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My 08 crf 450x has developed a slightly rough idle (when riding at very low rpms), and it is having difficulty cranking quickly right after turning it off.   Mine is street legal and I turned it off at a long red light (to keep from over-heating since no fan) and it took 30-40 seconds to get it to crank with electric start.  The second time it gave me a little trouble after turning it off and trying to crank it quickly, I pulled the choke and it cranked instantly.  After about 10 minutes it cranks instantly.  It cranks instantly when cold.  (all of this is with electric start)

Is the rough idle riding at very low rpms and the cranking issue related?  If so, is it valves starting to get tight?  Other? 

Also, I cannot kick start the bike at all.  It does not feel like the compression release is working?  It is a beast to kick down on.  Is there a way to test/adjust the compression release lever?

Thanks everyone for your help!!

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It turns over fine, but it doesn't fire instantly.  I just viewed a video on adjusting valves and from what he is saying, I don't think it's valves..???  I have a ton of compression.  I'm wondering if I have a little trash in a jet or in the carb?  Can you slide the carb around and remove the bowl without taking the seat and tank off.  If so, I could check the bowl and clean the jets from the bottom.   Also, would running a tank of race gas through it help?

Thanks for the quick reply!!!  I appreciate it.

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three things come to mind:

a. Are you using the hot start?  I know on my 450x, if I don't use it when hot, it doesn't start.

b. You may not be cranking over as fast as you should.   If you've never changed the battery out yet, it's overdue.

c. You may have some junk in the carb if the idle has gotten rough as you suggested.

Jim.

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Honestly, I don't recall a hot start button.  I put a dual sport button on it, and all I recall is the start button and the kill button.  I was told the small lever by the clutch lever was the compression break lever, but it does not seem to help reduce the compression.  Is that the hot start button? Let me look tonight for the hot start button.  That could be part of the issue.  Thanks again!!!!

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I just checked the PDF owner's manual and what I was told was the compression break is actually the hot start lever.  I have been using it.  That explains why it does not help reduce the compression when kicking it...lol.   It would take a seriously strong person to kickstart this bike.  I can get the kick start lever down, but I have to be standing on the bike on the kickstand to do it, and I still can't give it a hard kick.  I'm 6' and 175 lbs and never had this issue before.   I think we're down to a fuel issue at this point.

Thanks again!!!

 

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um....well one thing with the hot start, you need to release it as soon as the engine starts to catch. If you hold it in, the motor will die right off.

Jim.

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