RM125 quick question about adjusting power valves on a 01 RM125

B

badseed

2001 RM125 power valves...

one full turn "clockwise" is the stock setting....

will adjusting it get me a little better bottom end(hole shot)?

do I wan't it tighter "clockwise" for a better bottom end response?
or looser "counter clockwise" for better bottom end response?

Bike runs great 1st through 6th....but out of the hole I can hardly get it to spin the tire....
once it's rolling that tire is spinning!!!
but I can't get it to pull a holeshot....tire will not spin from a dead stop(it falls flat on it's face if I try to spin the tire from a dead stop..even in the sand).....


power valve adjustment?
or something else cause that problem?

has a new top end...
new plug...
new air filter...
fresh gas...
jetting is pretty much dialed in...
running 32:1 premix...
brand new clutch....

and can't spin the damn tire from a dead stop...it will fall on it's face or just plain stall....(even in the sand)

any idea's of suggestions ???
 
Mihylo33

Mihylo33

Non adjustable powervalve. It's an MX bike and a 125 to boot so there is no lugging this motor just 13000rpms of screaming and putting power to the ground. :drool:
 
B

badseed

Mihylo33:
Non adjustable powervalve. It's an MX bike and a 125 to boot so there is no lugging this motor just 13000rpms of screaming and putting power to the ground. :drool:
Click to expand...

Ok, thanks.....

Been riding bikes since I was a kid....I can't believe this thing won't spin the tire from a dead stop...not even in the sand :thumbsdown:....Thing is a embarrassment off the line :picard:
 
Mihylo33

Mihylo33

badseed:
Ok, thanks.....

Been riding bikes since I was a kid....I can't believe this thing won't spin the tire from a dead stop...not even in the sand :thumbsdown:....Thing is a embarrassment off the line :picard:
Click to expand...

This thing should be throwing you to the ground from a dead stop.
 
jackson409

jackson409

Who rebuilt it?

Oh and I'm not sure about the 125 but you can adjust the PV. Mine is only 1/4 turn from no tension so just as the tension starts i stop and I crank it down. If I turn mine one full turn the it runs like a YZ250 turd.
 
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Mihylo33

Mihylo33

Does it start easy and idle?
Without it being in gear does it rev easily?
Is the powervalve installed correctly?
Are the reeds in good condition?
 
PALMER84ONE

PALMER84ONE

jackson409:
:busted:Who rebuilt it?

Oh and I'm not sure about the 125 but you can adjust the PV. Mine is only 1/4 turn from no tension so just as the tension starts i stop and I crank it down. If I turn mine one full turn the it runs like a turd, I wished I had a YZ250 rebuilt by "THE DOCTOR".:hug:
Click to expand...

"ANY" 125 properly rebuilt, and jetted with a good clutch will throw your ass on the ground. :prof:
 
B

badseed

Mihylo33:
Does it start easy and idle?
Without it being in gear does it rev easily?
Is the powervalve installed correctly?
Are the reeds in good condition?
Click to expand...

Starts first kick every time....
Idle's great, in neutral it rev's fine (nice and crisp)...
reeds are in excellent shape, no cracks, chips, nothing...they have a nice snap to them, and can't see no light when looking through them(they have a great seal)....

I did the top end myself...arrow pointing towards the exhaust ports...(that's the correct way?)
had my local bike shop hone the cylinder for me.....
yes, the power valves are in correct....

If I take off slow then get on it once it's rolling...that back tire is spinning and the front tire is lifting....runs like a bat out of hell 1st through 6th gear...

if I try and take off spinning that rear tire (even in the sand) it will fall on it's face and/or stall...and that's with me sitting on the gas tank too....

never seen anything like it....can't spin the tire from a dead stop??? but once rolling it's spinning that rear tire while the front tire is lifting...

I have tomorrow off work, if the rain holds off I'll take it out and grab a video of it so you can see for yourself....
 
P

PawPaw

What gearing are you running?
You can add 2-3 teeth on the rear sprocket to gain low end response.
Also, remember to feather out the clutch on starts. These are very high reving engines, but they don't have much torque. Don't just drop the clutch at the start. Easy out with the clutch to keep the rpms up at the start. If done correctly, you will find better starts in second gear and feathering the clutch at the start.
Read this old post from another site. Look for videos at youtube.com as well
http://www.allthingsmoto.com/forums/f-28/feathering-clutch-34789/
Paw Paw
 
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