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98 cr 125 weird noise from new rebuild

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My top end went on m 98 cr 125, the needle bearing clip came out and broke apart and shrapnel got everywhere and blew it up. I cleaned out the top end and washed out the crank with the bike upside down. the bike starts up great and seems to run fine but im getting a weird di-di-di-di-di-di-di noise coming from the motor. i tried adjust the power valve and tightening everything but the noise is still there. Here is a link to a video where you can hear the sound. It gets louder as rpm's get higher and at really low rpm barely idling it goes away. I am pretty new to bikes and 2 strokes so any help would be appreciated.

https://youtu.be/msfU8WCXg8E

Edited by deanmellor

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If it is a wiseco piston or a forged piston they will knock like that until they heat up. (Like 4 min) don’t ride until fully heated up also while letting it heat up don’t let it stay at 1 rpm but don’t go over 1/2 throttle

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12 minutes ago, Jace Perez said:

If it is a wiseco piston or a forged piston they will knock like that until they heat up. (Like 4 min) don’t ride until fully heated up also while letting it heat up don’t let it stay at 1 rpm but don’t go over 1/2 throttle

yeah its a wiseco pro lite. thank you that helps me a lot 

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Yea than that your problem I have 02 cr125 same thing happened after I switched to wiseco forged piston they last long just make sure to let the warm up or you will have a cold seizure and lick up your topend

*lock up

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HMU with any other problems with the bike I’m like a cr125 guru I took apart and rebuilt my bike from scratch just HMU and I’ll be glad to help with any problems

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Just now, Jace Perez said:

HMU with any other problems with the bike I’m like a cr125 guru I took apart and rebuilt my bike from scratch just HMU and I’ll be glad to help with any problems

sweet man perfect thanks a lot for the help and i probably will

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If your talking about the clatter noise, its normal... For future refs, install the c-clips with the opening either up or down, never or back.

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On 1/24/2018 at 9:55 PM, Jace Perez said:

If it is a wiseco piston or a forged piston they will knock like that until they heat up. (Like 4 min) don’t ride until fully heated up also while letting it heat up don’t let it stay at 1 rpm but don’t go over 1/2 throttle

Wow thanks,

I've always been worried about a similar knocking I hear coming from my top end when I am warming up my '95 yz 125 - that also has a wiseco piston in it.

Good to hear its nothing bad!

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Wow thanks,



I've always been worried about a similar knocking I hear coming from my top end when I am warming up my '95 yz 125 - that also has a wiseco piston in it.



Good to hear its nothing bad!


No problem

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I have a 98 rm250 and it sound the same. The bike has never been blown up or damaged. 

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