Hi all, can any1 help. ????? 1999 R1

I have low down power, all fine, but i have now started losing top end power. I used to be able to sit at about 80mph in top gear and wind it on and the bike wuold lurch forward with the speed, but now seems when i do this there is nothing and it takes time to get the power on. I have also noticed alot more vibration threw the bike.

Im running akroprovic can and kn filter, it has been fine but has just now started losing the top end power, any1 got any solutions

regards Daz

Hi all, can any1 help. ????? 1999 R1

I have low down power, all fine, but i have now started losing top end power. I used to be able to sit at about 80mph in top gear and wind it on and the bike wuold lurch forward with the speed, but now seems when i do this there is nothing and it takes time to get the power on. I have also noticed alot more vibration threw the bike.

Im running akroprovic can and kn filter, it has been fine but has just now started losing the top end power, any1 got any solutions

regards Daz

probs needs a rebuild and a you should have had it dyno run with those exhaust and a K&N you may have posibly damaged ure enguin buy runing it lean because of the modifications could be quite costly

my guess would be worn main jets, as these tend to wear out. Is the end of the silencer sooty? does it strumble getting on the revs? If you do replace, dont use a dyno jet kit. google allens and jets.

It could be seized exup valve, electrical (plugs or coils) or maybe the valve job needs doing (something like evry 24,00omiles on an R1 can be sooner though if ridden properly) or even an air leak (manifold rubbers perish).

how mechanical are you? you could start to look at individual things and try to track it down. A dyno run might be worth a punt, would certainly say if the bike is rich.

good luck.

Hey there. I had the same problem with my 2000 R6. It would be fine upto around 100mph but after that it juddered and wouldn't carry on. I changed all the spark plugs and it was fine after that. I think one was dead. Hope this helps. Phil.

thanks for replys, bike was set up on dyno wen filter and can fitted. i have taken the exup apart and all if free, and working, servo tested electically, all working. Plugs are a nice tan colour and done compression test and all 4 within the specs. Valves sound the same, slight rattle but then again thats better than too tight.

So any more ideas please?

pitted pistons ???