[mhughes250]

HEY GUYS I AM NEW TO THE DIRT BIKE WORLD I JUST BOUGHT A 2004 CRF250 AND THERE IS A KNOCKIN NOISE COMING FROM WHAT SEEMS LIKE THE TOP END AREA. I HAVE TRIED TO READ AS MUCH AS POSSIBLE. I SAW SOMETHING ABOUT A CAM SHAFT BEARING, DECOMPRESSOR ANY IDEAS WHAT THIS COULD BE? THANKS FOR THE HELP.

[Asmith]

Welcome to the site!

Is the noise more noticeable at low rpms?

[mhughes250]

yea when i am at idol the higher the rpm's the the quieter the noise then it seems to go away when you give it some throttle.

[Asmith]

Then what you are hearing is the decompressor. Perfectly normal noise.

[mhughes250]

thanks for the help. I read alot since i found the fourm yesterday. And saw someone talking about it being a worn out timing chain could it be that? i read someone talking about taking the cam cover off and lubeing the decompressor arm pin is it hard to just replace this part?

[124]

The decompressor will make some noise, but not obvious enough to think something is wrong. Hearing sensitivities vary from person to person. Do you have another 250R to compare to? Is it more of a "clack, clack, clack" at idle? Pretty much goes away when you rev it? You have a classic noisy decompressor.

Check your PM's mhughes...

[mhughes250]

its higher at lower rpm's i dont have another 205r to compare to. its a noticable noice that my frined with a 450 noticed i am going to lube it up today and see if it helps.