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Posted

when power valve kicks in bike starts to stutter, can the power valve get stuck? how do you go about fixing it?

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Posted

Nice intro :rolleyes:

what you mean nice intro

Posted

If you cant see what i mean then it doesnt matter, try a Haynes manual

thanks for the help!

Posted

So, is the power valve the intake valve or the exhaust valve? :blink::mellow:

  • Moderator
Posted

So, is the power valve the intake valve or the exhaust valve? :blink::mellow:

Its a well proven servo driven rotary valve in the exhaust port that makes considerable changes to the exhaust port size and profile.

Its probably just a duff plug or low battery voltage.

  • Moderator
Posted

So, is the power valve the intake valve or the exhaust valve? :blink::mellow:

Its a two stroke engine, the power valve effectively changes the height of the exhaust port to give maximum power at different RPM's, ie a lower port for low RPM's and a higher port for high RPM's, it mas an electrical servo motor to match the power valve position correctly to the current RPM value.

Posted

Its a well proven servo driven rotary valve in the exhaust port that makes considerable changes to the exhaust port size and profile.

Its probably just a duff plug or low battery voltage.

But it would make a BIG difference on a 125, the valve that is?

  • Moderator
Posted

But it would make a BIG difference on a 125, the valve that is?

Gives the motor more flexibility, better power output over the range of revs, rather than just one defined power band, at least thats my view of it.

  • Moderator
Posted

But it would make a BIG difference on a 125, the valve that is?

It makes the low rpm power (relatively) much stronger on a restricted 12hp bike. On the full power versions its vital to keep the motor rideable, without it you have one extreem or the other.

Posted

Its a well proven servo driven rotary valve in the exhaust port that makes considerable changes to the exhaust port size and profile.

Its probably just a duff plug or low battery voltage.

been happening consistantly for a long time now. plugs alright battety is fairly new.

  • Moderator
Posted

Gives the motor more flexibility, better power output over the range of revs, rather than just one defined power band, at least thats my view of it.

Yep, you put it better than i did OG. I can hear the valve on my TDR changing as i ride. At least at lower sub warp rpm.

Above 6000rpm on a large throttle opening i frankly couldn't give a monkeys what its doing so long as it keeps doing it.

  • Moderator
Posted

been happening consistantly for a long time now. plugs alright battety is fairly new.

Hows the air filter.

Does a bit of choke make it better or worse.

And, when was the last time it had a good l o n g blast to clear out the tubes.

Posted

Hows the air filter.

Does a bit of choke make it better or worse.

And, when was the last time it had a good l o n g blast to clear out the tubes.

choke makes no odds, it kicks in the revs get to redline and it's like the power shuts of then comes back repeatedly till you grab the clutch

  • Moderator
Posted

choke makes no odds, it kicks in the revs get to redline and it's like the power shuts of then comes back repeatedly till you grab the clutch

Its supposed to do that, its the rev limiter stopping the engine from destroying its self.

Posted

How do you know the power valve is at fault?

Did you have the cover off and watching it to see or what?

EDIT: sorry Cynic didnt see your post. Yes it is supposed to do that.

  • Moderator
Posted

How do you know the power valve is at fault?

Did you have the cover off and watching it to see or what?

EDIT: sorry Cynic didnt see your post. Yes it is supposed to do that.

:D i had the same on another topic with OG.

Guest MaD.VeZ
Posted

Its supposed to do that, its the rev limiter stopping the engine from destroying its self.

Strange as mine just revs and revs, no fluctuations like a rev limiter would cause. Destroyed the odd engine or two before now  :blush:.

After though: Unless its the model with the speed restriction. http://www.dtr125.net/tuningf.htm < try here nedery , select your year at the top. (if you haven't already). 

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