HELP!!! My GS650G Tops out

[mybadkat]

Hi I have just done up the top end of my 650 Kat thinking a valve prob was causing the ole girl to flatten out at 80kph at around 5000 t0 6000 rpm but this hasnt change anything .
It has perfect idle, faulters a little at very low rev when taking off but absolutely stings from then till I hit mid range then looses power until I slow down to around 3000 t0 4000 rpm and stings again
Then It happens all over again
Balanced the carb butterflies YES
Checked cam timing YES Fuel seems to get through to carbs fine.
I'm at a loss ,any ideas?

[Dave8338]

Hi I have just done up the top end of my 650 Kat thinking a valve prob was causing the ole girl to flatten out at 80kph at around 5000 t0 6000 rpm but this hasnt change anything .
It has perfect idle, faulters a little at very low rev when taking off but absolutely stings from then till I hit mid range then looses power until I slow down to around 3000 t0 4000 rpm and stings again
Then It happens all over again
Balanced the carb butterflies YES
Checked cam timing YES Fuel seems to get through to carbs fine.
I'm at a loss ,any ideas?

Sounds like you're running out of petro! Have you gone through the fuel system to ensure that there are no kinks in the line? Air vent in the fuel cap open? Are you runing an external fuel filter? Have you checked your float height setting? Any air leaks anywhere....anywhere? Stock airbox or pods? Stock exhaust or piped and jetted...jetted? If all comes back as yes and stock, you may have to bump your jet needles up a bit.

Let us know.

[prxbadger]

sounds like a slight blockage in your main jets

its the transfer between pilot jet and main which causes the falter

i bet if you whack back the throttle at 5000 rpm it will take off again

[brveagle]

I'm betting your plugs are chalk white... Is the jetting stock?
Stock pipes/Air filter? Do you have the airbox on? Lid too?

[chef1366]

Might be a bad petcock or as said a kinked fuel line. Try running it on prime and see what happens.

[8trackmind]

You have an intake leak.
The boots between the airbox and the carbs to be exact. (Carb to engine boots would cause a high idle)
One of your boots is either not seated, (center, no doubt) or torn. Believe it or not, it only takes a very small leak to cause CV carbs not to work properly.
If you do end up replacing the boots, get new clamps too.