HELP!!! 07 ZX6R Won't Rev Past 10k, Seems to be Running Hot and Lean!!! | GTAMotorcycle.com

HELP!!! 07 ZX6R Won't Rev Past 10k, Seems to be Running Hot and Lean!!!

burg226

Well-known member
I recently acquired a clean 07 ZX6R Track Bike from a very meticulous owner. Before winter storage last year he changed the spark plugs, oil, filter, air filter, fresh V-Power and stabilizer.

When I went to buy the bike we were running it in the garage and it wouldn't rev past 10k. It would rev up to 10k then rev down to about 9k and eventually hold around 8k. I tried this a bunch of times and it continued to do this. I still bought the bike and got an even better deal on it now knowing that there was this issue.

After bringing it home I got rid of the old gas and put some fresh V-Power and SeaFoam in it. Still wont Rev past 10k. When running it for a few minutes in the garage I noticed the header and cat were literally almost melting (they were bright orange and almost melting the lower fairing). But the rest of the exhaust was regular temp and not red hot.

After tearing it down a little last night this is what I am finding:

1. Fuel lines not obstructed and connected properly
2. Air lines not obstructed and connected properly
3. All wires and harnesses connected properly, plugs and plug caps connected properly
4. Fuel pump is cycling and working properly
5. Battery is new and fully charged
6. Brand new air filter
7. 4 brand new spark plugs (NGK CR9E) but appear to be running lean (Pics below).
8. Fresh oil and filter
9. No error codes or flashing lights

Does anybody have any ideas what is going on here? Why won't it rev any higher than 10k? The redline is 16k. Why is the header and cat glowing red hot? Is there an obstruction in the cat possibly? Injector issue? Any other ideas? Anybody else experience this before? Do you agree that these plugs show that it is running lean?

Bike is all stock except an Akropovic slip-on.

Any help would be most appreciated.
 

Attachments

Evoex

The God
Site Supporter
Damn! Interested to see responses to this.
 

miggs

Well-known member
Site Supporter
Does the ZX use a secondary throttle valve?

I remember this was a common issue on mid 2000's gsxrs.

The sensor would fail and not allow the throttle body butterfly's to open fully and allow the bike to rev past about 7000rpm.
 

HERBXX

Well-known member
I would check your fuel pressure if you can for a clue . If its low it will cause the above issue .. Look up the correct reading and get a gauge , I have no idea if yr bike has a test fitting on the fuel rail or not ..
 

GreyGhost

Well-known member
Site Supporter
Plugged (melted?) cat could cause your symptoms. Try running open header and see if your problem is solved (it will be LAF so pick a time where you will piss off the fewest neighbours). A power commander or bazazz is probably cheaper than a new cat and will get you mo powa if that turns out to be the problem.
 

Blackfin

Well-known member
Site Supporter
My guess would be the cat as well.

Super-hot EGTs can be caused by retarded timing but the way you describe the engine settling back down to ~8K suggests a buildup of backpressure and a retention of a great deal of heat, probably caused by a plugged or collapsed cat. If it's a track bike, heave it and save the weight.
 

burg226

Well-known member
Thanks for the replies everyone. Please keep them coming. I will inspect and clean the fuel filter inside the tank hopefully tonight or tomorrow and test the fuel pump at the same time. After I put it back together I'm going to tear off the headers and cat to see if they are blocked or melted.

The previous owner stated it ran perfect before he stored it (and I believe him as he is a very honest seller and well known track day enthusiast) so I'm somewhat leaning towards it being a clogged fuel filter or fuel pump.

I'll keep everyone posted. Please keep the replies coming in the mean time!
 

burg226

Well-known member
Fuel pump is on order. Hopefully this does the trick. Seems like a common issue on these bikes. I rented a fuel pressure gauge and the reading shows much lower than the spec. I also did a flow test and it is flowing at less than half the machines spec.

Fuel pump should arrive and be installed later next week. Fingers crossed this does the trick!!!

The bike runs and idles amazing besides this RPM/revving issue.
 

HERBXX

Well-known member
Fuel pump is on order. Hopefully this does the trick. Seems like a common issue on these bikes. I rented a fuel pressure gauge and the reading shows much lower than the spec. I also did a flow test and it is flowing at less than half the machines spec.

Fuel pump should arrive and be installed later next week. Fingers crossed this does the trick!!!

The bike runs and idles amazing besides this RPM/revving issue.
Thanks for the feed back !
 

Top Bottom