yz426f 01 - 3/4 to Full throttle power loss

2 replies to this topic
  • Guest_kokinyapussbiarch_*

Posted May 02, 2005 - 04:59 AM


G’day all.
I just purchased 426 01 and the bike is pulling well through the bottom end and mid range :D , however it looses power about ¾ throttle onward :D .
When it does this, there is no backfiring; only a noticeable power loss.
Surely this can be typical... I reckon I’ve have a problem :naughty: .
Having said this though I’ve never owned a four stroke before.
What do you blokes reckon :D ?

( :naughty: Ps, The bike is stock. Idles well starts first kick (hot or cold). Got a new spark plug, fairly clean oil and filter, premium fuel and is being ridden at about 300 meters above SL)

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  • grayracer513

Posted May 02, 2005 - 06:43 AM


At 3/4 onward, you're on the main jet pretty much exclusively. Start by checking the jet for an obstruction.

If you bought it from someone who lived at a highere altitude, it may be too lean for where you are.

If the jet's clean, I'd try going up a size and see what comes of it.

  • Guest_kokinyapussbiarch_*

Posted May 02, 2005 - 02:44 PM


Cheers mate

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