im losing all my power low down in the rpm range is there anyway to get more power down here? it feels like its peep is gone no pick up at all? its a intermitted problem ive looked at the coils but seem fine ? could it be fuel? carb? spark? problem anyonw else got this problem with the SP gear box any remidies or ideas thanks

Power valves stuck open?
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

yeh it feels like that cos this morning it was running like a slug then all of a sudden it fixed itself again and wow what a difference! it sounded like a tennis ball had just fallen out of the intake plume and it cld breath life again? do you think i should take it to a spanner happy mechanic to have alook or will some valve cleaner in the fuel fix the problem?

No, and no.

Check the cable tension. It should have a little play, but not much. About 5mm deflection I believe.

Check that the valve is actually rotating - swivel it by hand with the igntion off, and then turn on the ignition. The valves should return to low setting.

Check they 'jiggle' a bit when idling, and move when you gently blip the throttle.

Have you cleaned them at all? Carbon builds up and makes them very stiff to move.

Beware!! if the motor struggles to move the valves for whatever reason, they draw a lot of current, and have a tendancy to kill the PGM, which will cost you up to £500 to replace.

Check these things and get back to us.
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

This morning was running fine again, where is the power valve located is it on the intake manifold, I havent worked on a NSR before what is the exact location of the valve so i can have a look?

sorry im a bit clueless when it comes to engines

Exhaust side of the cylinder. There's a pair of cables going to a pulley on each. Can't miss it!
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

thanks for that yeh i see the cable was loose tightened it up and its running better!, is ti worth taking the valve out for a clean cos its proably never been done? just unbolt it from the manifod do I?
also is there one on the upper cylinder as well?

cheers alex

Yes there is one on the upper cylinder. Since it worked loose probably is worth checking the adjustment. Clean it if you like, can only make things better, but if they've never been done they can be a little tricky to extract. Adjusting will take no time at all if you use the markings and/or the alignment holes. If you follow the more accurate procedure described on this site it could take significantly longer though if it's the first time.
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