Custom Fighters - Custom Streetfighter Motorcycle Forum banner

1 - 5 of 5 Posts

·
Kyle M.
Joined
·
6 Posts
Discussion Starter · #1 ·
Hi All,
I have a 1991 GSXR1100. Right at 4500 RPMs the bike losses power. This is a bit annoying because it is right around 60-65 MPH a nice cruising speed. It happens through all gears. If i hammer the throttle through it it is fine, but if i just hold it steady the exhaust pops and the bike kinda spits a sputters. If i slowly roll by 4500 RPMs it pops a couple of times then carries on as normal, and if I slowly roll out of 4500 RPMs it bogs down for a second or two then i regain power. Ill attach picture below of some of the mods i have. Exhaust, two k&n air pods, carbs are jetted. new plugs, DYNA 2000 ignition, wires, and coils. I thought maybe the new ignition system would cure it with a stronger spark. Still the same as without the aftermarket ignition system. Carbs and fuel system was just cleaned as well.
All suggestions welcome, PLEASE HELP! THANKS!!!

 

·
0.o i didn't do it
Joined
·
1,892 Posts
If it has an adjustable needle you could drop the clip down one notch. That would enrich the mix some in that area. The other possibility would be to raise your float level up a mm and see if that helps. Try either one and test. If one dosent work try the other.there are carb tuning guides out there. Factory pro has a good tuning guide for cv carbs. GL

Sent from Motorcycle.com App
 
G

·
Its just come fully on to the main jet at that revs, its definately a carb problem you need to smooth the crossover (from pilots to mains) by richening the mixture via air screws or dropping the needle or even both
 

·
Registered
Joined
·
740 Posts
I would try...

Lift the needles one clip (move it one slot closer to the pointy end)

Enlarge the pilot jets one size (eg 50-> 55)


You might also cut 1-2 turns off your diaphragm springs. This can be done on any bike safely to slightly reduce spring pressure, which leads to a crisper response and the needles opening slightly earlier.

4500 is right at the transition between pilot and main circuits. The needle restricts the main from about 1/4 to 3/4 throttle, WOT it's totally lifted up and fuel is governed by the main size. If WOT pulls and top end are OK, your main jet is fine.
 
1 - 5 of 5 Posts
Top