lower performance in gears

[legsroses]

Hi,
my 2010 bike reached lower speed than standard.. not 50mph but 40 (1gear), not 87mph but 63 (2gear), not 106mph but 84mph (3gear).. for dealer is all ok, diagnostic is ok too.. so I don't know as solve it, someone can suggest something about..
Thanks

 

[steve59]

is the engine reaching redline?

 

[roame]

any chance your clutch is slipping?

 

[legsroses]

is the engine reaching redline?

I perceive physical sensation, like when it reach redline.. moreover I feel roar sound like so..
it seems however begin before when it should do..
I think but, effectively, I'm not sure.. so because I don't use, since 2011, any tachometer..
which stock odometer-rev counter wires

 

[legsroses]

any chance your clutch is slipping?

I'm enough sure it isn't so

 

[Jag]

Clogged fuel filter?? Would be my guess.

 

[legsroses]

Clogged fuel filter?? Would be my guess.

I'm pretty sure it isn't.. fuel pump, as other things nearby to it, it's ok

 

[rocketjohn]

If the engine is good condition overall, there remain only three things.....air, fuel, spark. Among these you may need a clean air filter, a new fuel filter, and/or new spark plugs. Or you may need all three.

 

[R-III-R Turbo]

The speeds you report all come in at 5500rpm.
That's pretty accurate point to reach top speed per gear, so that sounds like you are hitting a limiter.

Are you getting these speed readings from the speedometer or a GPS device?
What specification rear tyre are you running?

Assuming speedo readings; given your bike's modifications I would point first at the accuracy of the speedo. You can use an app on your phone to get accurate speed, and verify speedometer circuit accuracy.

After that - have you got tuneboy or tune ecu?
Hook it up and see what your rev limit is set to.
And while you're there, check speedo calibration adjustment (assuming you read your speeds from the speedo and not a GPS)

Also on my 2010 Roadster 6500rpm in 2nd is about 80mph, not 87. The other 2 speeds you give correspond however.

 

[legsroses]

If the engine is good condition overall, there remain only three things.....air, fuel, spark. Among these you may need a clean air filter, a new fuel filter, and/or new spark plugs. Or you may need all three.

engine ok, except this.. this July I bought new spark plugs, since then I did few miles moreover.. I use washable K&N, I removed bearclaw and airbox too, with other filter and one sensor too.. K&N Rubber Base Filter for Air Temp Sensor | Flipmeisters Specialty Products K&N Rubber Base Crankcase/Vent Filter Replacement | Flipmeisters Specialty Products fuel filter instead it's always the same