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Joshy1992

Joined:

Jul 12

Posts: 5

Joshy1992 says:

KMX 125 PROBLEM PLEASE HELP!

Hi everyone. I have a kmx 125 which i love! But the only this is that when i full throttle the bike. It over revs after 6-7 thousand ( not powerband lol) and looses power. Now i thought this was the clutch so i go a new one. But then after recieving it. Its impossible NOT to stall the bike. And took it to my friends grandad who is a master with all motocross bikes. I.e after every race my friend has his whole engin re-furbed and cleaned new oil ect. He wasn't too sure what it could be. I think it could be my power valve sticking open after looking on web. But not 100% sure on how to fix this. Im pretty sure its not restricted as i can still hit 80+ no prob. Just have to fether the throttle so it doesn't spin!! HELP! :)

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  • Posted 2 years ago (27 July 2012 14:03)

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jaffa90

Joined:

Mar 09

Posts: 8787

kcmc

Joined:

Jan 08

Posts: 7076

kcmc says:

Hey

Jaffa wind yea neck in :lol: ooooo, i do luv two strokes

 

Hi Joshy1992 and welcome to the site:smile

 

Am sorry mate,i don't understand what you mean at all,are you foreign and translating into English ? what is your country of origin?maybe Master Grandad should take another look see!

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Joshy1992

Joined:

Jul 12

Posts: 5

Joshy1992 says:

kcmc

haha im not foriegn!!! lol. Basically. if i start from 0mph and full throttle 1st 2nd 3rd ect.. when the bike picks up from say 6-7000 rpm. Its looses power and goes from that 7000 straight to 10,000rpm. Almost like the clutch is slipping.. but the clutch is fine. had it out and checked all over. Only thing left is power valve. but not sure what to do here. Grandad has moved away so hard to get to now! :(. Its not clutch because its impossible to NOT stall it.

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kcmc

Joined:

Jan 08

Posts: 7076

kcmc says:

Kawasaki KMX 125 year?model?

Hi again Joshy1992

I would not say this is a power valve problem,if the valve was stuck open you would feel a lack of drive at the bottom end of acceleration,if it was stuck closed(which is the most commen situation)you would feel or have no top end RPM and the engine would not get into its power band as effectively the exhaust port is partially blocked with two barrel type power valves.So i hope you understand this?,so now its down to have you rebuilt the clutch properly?and have you put the correct oil in the gearbox?(what oil did you use?) if you are confident you have then i would say with the very sketchy information you have given its more than likely the chain jumping over the sprockets as it hits the power band. Check the engine drive sprocket for severe wear or teeth missing and the rear for much the same.Good Luck

KCMC:tongue: 

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Joshy1992

Joined:

Jul 12

Posts: 5

Joshy1992 says:

Reply to KCMC

I took the bike like a said to my friends grandad. He already had the stuff to hand. as he has 1 kmx 125 1 kx 125 1 kx250 four stroke. and 3 KTM 250 two strokes. Which he enjoys to play with! lol. Anyway im not too sure what stuff he uses. On the mot recently it had new chain and sproket hit so doubt its that. But when i take the powervalve cover off (right hand side not the one with 'kips' on it) and rev it. it does open but stay slightly open a bit when letting off the throttle. Almost like its sticking? But i believe taking it to a motorbike garage wont help as when i took it to the local garage. He goes -  needs hell of a lot mate. I said like what. He said not sure but can imagine a list. Took it to my mates grandad and he called them and said he's coming down to discuss. They didn't want to know then. But now the old F***er has moved away and left me in the dark! :-(.

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eatcs01

Joined:

Aug 02

Posts: 3251

eatcs01 says:

KMX

If the revs jump from 7000rpm to 10,000rpm WITHOUT any increase in speed, then either your clutch is slipping (that's my bet), the chain is jumping over the sprocket teeth (it would make a hell of a noise too), or you're spinning the rear tyre up (the bike ain't powerful enough for that).

Just because it stalls doesn't mean the clutch ISN'T slipping. I reckon the clutch is goosed.

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Amateurcynic

Joined:

Jun 09

Posts: 1039

Amateurcynic says:

Just a thought

If, as you say you've fitted a brand new clutch (after soaking the plates etc) have you checked the condition/routing of the cable? If it's frayed or kinked somewhere it may cause the symptoms you're describing

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kcmc

Joined:

Jan 08

Posts: 7076

kcmc says:

As

the guys say.

Its one of these that's been mentioned,But which one?:smile

Its a Mystery:shock:

 

http://www.youtube.com/watch?v=hgee3IGYZsU

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Joshy1992

Joined:

Jul 12

Posts: 5

Joshy1992 says:

Reply to all.

Thanks for your help guys! I never actually fitted the clutch as he said it didnt need it! I take it this is going to be my problem!! Can anybody advise what i'll need. I already have new clutch plates at home..

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preunit

Joined:

Dec 10

Posts: 11879

preunit says:

"Can anybody advise what i'll need"

A spare weekend and unlimited tea.:biggrin:

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