96 GSX-R1100W with possible 41 Flat Slide Keihin Carb issues

[MediAndy]

 

I purchased a 1996 GSX-R1100W with 7k original miles on her about two month ago out of Baltimore (I'm from NC). She has an aftermarket exhaust and 41mm Keihin flat slide carbs with direct air intake (without a filter).

 

She died on me the first time that I took her out for a ride right after I got her home, so I gave her to a local shop and told them to do whatever she needs to get her right. They did a full service, and it turned out that a bushing on the alternator was bad, which was the reason why she died on me. They also replaced all plugs, which all showed a black carbon buildup on the electrodes. I am running 93 octane, ethanol free fuel with a Techtron fuel cleaner added.

 

So I rode her this afternoon, she did fine as long as the rpm's were around 3k plus, and if we were not stuck in stop and go traffic. I rode into the city, and had to stop an many occasions due to red-lights and heavy traffic. She started to give off a couple of "Puffs" sounds, almost like she got vapor locked, which lasted while we were stopped at a light, and then the puffs stopped after we got going again. It did take some higher rpm's to get her cleared up however. It seems to me that she is getting way to much fuel, and therefore sputters and putters at low idle speeds, but absolutely takes off like a rocket as soon as the rode is open like on the highway. There is absolutely no hesitation when you get on the throttle and speed up. There are also no issues when running at 70mph or faster. She runs as smooth as smooth can be.

 

So, my question is probably the obvious! Are 41mm flat slide carbs to aggressive for lower city speed riding? If not, should I get the carbs cleaned and re-jettet, or would I be better off selling the 41mm and get me some more down to earth carbs? I don't know anything about this bikes history or the carb specifications, so I am a little stuck here. I do know that she was sitting in storage for almost 13 month before I bought her.

 

I am lso a little concerned about not having any filters on the carbs, so does anybody know if my carbs could be retrofitted with a filter system?

 

But I do like the way the 41mm Keihin Flat Slides sound and performs, so I hope that keeping them and having them re-jetted and cleaned will be the answer.

 

Thanks,

 

Andy

[banoffee]

Moved to water cooled.

[KATANAMANGLER]

I dont know much about Keihins but a carb is a carb. Try to identify which throttle position is at fault rather than RPM. The throttle position will tell you which circuit is at fault. If it's overfueling from closed to 1/8th -1/4 throttle then chances are the circuit at fault is the pilot circuit. Sounds like the needle and wide open throttle circuits are doing the do from your discription.

The pilot circuit is metered by the pilot jets and can also be adjusted by leaning out the mixture screws. If the mixture screws are wound to less than 1 turn chances are you need to go down 1 pilot jet size.

A flatslide race carb with bellmouths  is never going to be as civilised accross the board  as a standard CV standard carb with an airbox, full stop. They are designed for doing what your bike appears to be doing well. Taking off like a scalded cat.

You could consider some foam socks for the bellmouths if you are worried about the intakes but  not before you cure the over rich idle circuit because any reduction in air flow would just make it worse.

[Sheep]

They still do 93 Octane fuel!!