No power at mid to high revs

[2beta_than4]

Hi guys been having trouble will my zx9 2001.

In top gear at 120km I give it gas to to pass and I might get to 130km if Im lucky and it wont go my more. Its not sputtering it like a massive flat spot.
Or if I chop it down a few gears and get the revs up it has more power but as soon as I button of the bike dies then have to sit on the side of the road and crank it over for a while.
At low revs and up to 120km if feels normal and has the normal power.

It started doing it about 2 years ago but had to it stored for a while ( Dam wedding and kids coming along.)
Got it out and put new plug in it last summer and thought it had solved it or I was to chicken to go that fast again. Until last weekend it starting missing and went back to do its thing again.

Turned around and got back home and all the plugs where black and the exhaust pipe too. The fumes stunk of gas.
Cleaned the plugs and took the air filter out and tied again. Same thing happened. Ordered new filter.

Any idea on what to try next?
Havent played around with 4 carburetor before. Yet.

Thanks

[The Reibz]

Possibly a lean condition from a leaking seal. They crack a bit and go hard after many years. Check those before diving into the carb

[pete-blen]

If yer motor will rev out..but is making no power... 90% of the time it's Lean...VERY LEAN..

[Rhys]

Blocked main jet

[Akzle]

fuel starve

[mossy1200]

Low level fuel sensor playing up or unplugged? Bike into limp mode.

[skippa1]

Turned around and got back home and all the plugs where black and the exhaust pipe too. The fumes stunk of gas.

Thanks

The conditions above would point to rich not lean IMHO

[ducatilover]

New petrol
Check for intake leaks.
Make double certain the ram-air is sealed (where my money lies)
Clean the carbs, sync them too
Check for fuel flow
Check coils/leads
Do wheelies



Flat/no power but still revving is usually lean. Rich feels very boggy and stuttery.

[skippa1]

Flat/no power but still revving is usually lean. Rich feels very boggy and stuttery.

Rich also stinks of gas and carbons up everything

[ducatilover]

Rich also stinks of gas and carbons up everything

Ultra lean can too if it can't ignite.
But it's as common as muck for something to go wrong in the ram air.

[actungbaby]

Hi guys been having trouble will my zx9 2001.

In top gear at 120km I give it gas to to pass and I might get to 130km if Im lucky and it wont go my more. Its not sputtering it like a massive flat spot.
Or if I chop it down a few gears and get the revs up it has more power but as soon as I button of the bike dies then have to sit on the side of the road and crank it over for a while.
At low revs and up to 120km if feels normal and has the normal power.

It started doing it about 2 years ago but had to it stored for a while ( Dam wedding and kids coming along.)
Got it out and put new plug in it last summer and thought it had solved it or I was to chicken to go that fast again. Until last weekend it starting missing and went back to do its thing again.

Turned around and got back home and all the plugs where black and the exhaust pipe too. The fumes stunk of gas.
Cleaned the plugs and took the air filter out and tied again. Same thing happened. Ordered new filter.

Any idea on what to try next?
Havent played around with 4 carburetor before. Yet.

Thanks

bring over to palmmy i look at it and store it in my garage hehe no charge

what did the spark plugs look like they should be like 50 cm long white etc

[F5 Dave]

Hi guys been having trouble will my zx9 2001.

In top gear at 120km I give it gas to to pass and I might get to 130km if Im lucky and it wont go my more. Its not sputtering it like a massive flat spot.
Or if I chop it down a few gears and get the revs up it has more power but as soon as I button of the bike dies then have to sit on the side of the road and crank it over for a while.. . .


That bit makes me think fuel starvation. Crud in tank becomes crud in carbs, blocked tank vent, tap, & the evil aftermarket fuel filter that always causes a kink in the fuel lines, just enough to be a problem (Right Angle ones look a better bet).




. . .
Got it out and put new plug in it last summer and thought it had solved it or I was to chicken to go that fast again. Until last weekend it starting missing and went back to do its thing again.

Turned around and got back home and all the plugs where black and the exhaust pipe too. The fumes stunk of gas.
Cleaned the plugs and took the air filter out and tied again. Same thing happened. Ordered new filter.
. . .
That bit makes me think those dreadful Mikuni carb (think ZX used) which blight several Yams & Snoozukis. Emulsion tubes wear oval & wreak havoc fouling the plugs. Once fouled they may or maynot (usually not) recover even if they spark in free air test.

Pull the carbs out & give proper clean, remove & blow air through every jet (don't poke wire). Take out emulsion tubes & inspect with very good light & mag glass if poss. Replace if slight ovalising. new plugs.

Check factorypro website, have to dig in a little, but search emulsion tubes. Dynojet needles used to be great for damaging tubes as they were so rough.

Hmm here you go, Keihin not mikuni, look on left & follow links.

http://www.factorypro.com/

[2beta_than4]

Hey guy, thanks for the all the advice hopefully I can start looking at bike this week.

Could it be the throttle position sensor?? Is there a way the check this as the manual says to take it to the shop as you need the proper tool.

[F5 Dave]

I doubt it, but if you feel like it its just a potentiometer.

Unplug it & measure the resistance at the plug with any multimeter you can lay your hands on (~20 at supercheap perhaps) switched to ohms. Twist the throttle & see that the value changes & doesn't drop out at nothing during operation. That should be as good a test for a starting point.