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2004 crf250r compression

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so i have a 2004 crf250r and it is takes close to 40 kicks to start. the other day i couldn't get it to start at all, and it feels like there is no compression when i am kicking it. i can literally push the kick starter down with my hand. the first thing i did was check the valve clearances and i have one bad intake valve. my question is, does one bad valve affect the compression of the piston? or could my piston rings be bad?

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I also have a 2004 crf250r.... Just took it in for a new top and bottom end. If you have no compression you need a new top end so I would take it to a shop and have the "pros" do it for you.... It won't be a cheap repair but if you want your bike to start you need to. No compression, no riding. This just happened to my buddies quad where it has no compression.

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Yes one valve can cause you to loose compression because it's not seating all the way.

Most likely you do not need a new top end. Reshim your valves (if there is still room to shim them) and see if it will start. It takes 30 mins to Reshim them. If you are at the smallest available shim, then you will have to have the head redone with new seats, guides, valves, springs, keepers, and if your that far put a new piston in it.

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Like said above shim the valves and see if it starts. Check the clearances again after a couple hours, if they have moved again in short time you should change the valves before you get to the snallest shim, it wont be long anyway.

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say my problem was the one bad valve, if fixed will it be less of a problem starting (less than 10 kicks)?

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say my problem was the one bad valve, if fixed will it be less of a problem starting (less than 10 kicks)

you answered your own question.

 

without compression a motor wont run properly if at all.

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see if your local auto parts store has a loan a tool program and get a compression tester from there if u don't already have one just make sure its the one with multiple adapters,  

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