Engine stops pulling at 7k

[jwhelan65]

Ok here is where I'm at..

Swapped igniters still is bogging at about 6-7k

Ran it with the cap off and it still boggs out..

Completely dis-assembled gas cap, cleaned and put back together but I am still getting a hiss when I open the tank.

Bike fires first try

Float levels maybe?

[goggleboy]

did someone mention fuel filter, petcock screen, and fuel line routing from the petcock yet?
(didn't read every post)
I'm having the same issue right now, and I'm about to chuck my fuel filter and run a straight line down to the carbs.
.....I read the poll thread on fuel filters and it was very interesting

[jwhelan65]

did someone mention fuel filter, petcock screen, and fuel line routing from the petcock yet?
(didn't read every post)
I'm having the same issue right now, and I'm about to chuck my fuel filter and run a straight line down to the carbs.
.....I read the poll thread on fuel filters and it was very interesting

Its possible, but the petcock and lines are all new..

[atb1998]

engine stops at 7k

I was starting to wonder the same thing about petcock and fuel lines.. If the petcock is new, does that include the filter inside the tank? If the gas cap looks that bad what does the inside of the tank look like? Had a very similar problem on a yamaha. Under high rpms it would starve out. After cleaning out the gas tank really well. Never had another problem. Had gunk and rust sitting down low where it could not be viewed without a scope. Was surprised how much stuff flushed out. I also went thru a VERY long list of problems to find it was something stupid simple

[jwhelan65]

I was starting to wonder the same thing about petcock and fuel lines.. If the petcock is new, does that include the filter inside the tank? If the gas cap looks that bad what does the inside of the tank look like? Had a very similar problem on a yamaha. Under high rpms it would starve out. After cleaning out the gas tank really well. Never had another problem. Had gunk and rust sitting down low where it could not be viewed without a scope. Was surprised how much stuff flushed out. I also went thru a VERY long list of problems to find it was something stupid simple

Tank was treated with POR 15 no issues there.

[srsupertrap]

What was the result of the voltage drop test at the coils at various rpms, above and below the problem rpm of 7K. Okay I take it

[waterman]

Tank was treated with POR 15 no issues there.

Are you using an in line fuel filter? If so, try running without. My KLX wouldn't rev out do to a slow flowing fuel filter. May try a temporary gas tank on a test run to rule out tank filter and petcock. Just strap temporary tank down securely, hitting 9 K while holding tank isn't very fun or safe.

[jwhelan65]

What was the result of the voltage drop test at the coils at various rpms, above and below the problem rpm of 7K. Okay I take it

Have not done this yet

[Spyderman]

sounds like the problem i had with my 1000
see this thread

http://www.thegsresources.com/_forum/showpost.php?p=1035600&postcount=1

the fix for me was to increase the fuel line size and i put a high flow fuel filter from a late model CBR1000 in place and presto my problem was gone never to return i have no problems now pulling to redline in 5th at WOT
might be
that you have the same sort of problem with fuel flow
just a thought

[Nessism]

Hey Joe,

This bike had a header before right? Did you verify the jet numbers are the same as stock when rebuilding the carbs and switching back to a stock exhaust?

[jwhelan65]

Hey Joe,

This bike had a header before right? Did you verify the jet numbers are the same as stock when rebuilding the carbs and switching back to a stock exhaust?

Yes I purchased the stock jets from Z1..I just noticed the vent hole is plugged from the POR 15 tank treatment near the top of the cap...do you think maybe that could be it?

[hikermikem]

Yes I purchased the stock jets from Z1..I just noticed the vent hole is plugged from the POR 15 tank treatment near the top of the cap...do you think maybe that could be it?

Yup, you need that vent hole open to allow air into the tank as the fuel is leaving.

Poke it open & see what happens when you go for a ride.

[Nessism]

Yes I purchased the stock jets from Z1..I just noticed the vent hole is plugged from the POR 15 tank treatment near the top of the cap...do you think maybe that could be it?

Joe, thought you said in a different post that the bike was performing the same way without the gas cap installed? If so, I doubt that hole is the problem.

[jwhelan65]

Joe, thought you said in a different post that the bike was performing the same way without the gas cap installed? If so, I doubt that hole is the problem.

I ran the bike with a shop rag in the cap hole thinking that would allow air and it reved out to about 9k and than it progressively went back to the same problem. I'm going to try I few different things today and see if I can pin this down.

[jwhelan65]

Ok same problem

Igniter replaced

Tank vent cleared

The problem is now intermittent..carbs are coming off again.