Factory Pro Stage 3 jetting HELP! makes no sense

[race2win]

In need of help!

I have a 93 gsxr 750 with a stage 3 factory pro kit K&N air cleaners on it. New emulsion tubes maye 500 miles max on them. The kit comes recomondation setup is with 147.5 main jets. The bike will not pull to ******* with these mains so I went to 145, a little better 142.5 is the best yet. I can make a pass pull a plug and it looks a little on the rich side still but not bad. Cruising trough the pits the bike wants to bog alot I have to give it almost 1/4 gas to clear it out. The bike has stock pilot jets in it!? After cruising back through the pits then pulling a plug its sut black? I have cleaned the carb many times, new plugs, just installed new igniton coil and plug wires still does the same thing any ideas? Thanks

[johnnyracer]

Float height correct? Their jet kit needs to have the correct float height to be right on. Or maybe the air screws on the bottom end. Does it start good and idle fine? I am still working on my stage one. to get it right.

[race2win]

just put 140 mains in it did a few highway pulls top end feels much better and the plug looks awesome. cruised back to the shop felt it chuggin again checked plug and sut black. sooo I was just thinkin what you were saying I matched what FP wanted 15mm but I think im going to lean the floats out now and see what kinda difference it makes. What kinda bike are you running?

[race2win]

also when the bike is at a idle when I rev it up around 3 or 4k i get some dark smoke it clears right out think float height? the bike idles great so I dont think pilot jet?

[fj1289]

Did you reset the idle mixture? Is the low speed problem worse with the engine cold or hot? Will it start without choking it? Also, check to make sure the chokes (actually enrichers) aren't hanging open slightly.

Sounds like the needles are OK, just the idle is rich.

[race2win]

did some riding around after adjusting the floats it feels slightly better but still has a boggin spot, if I crusin in say 3rd gear around 3500 or 4000 rpm and give it just enought gas to keep it going at that speed its fine soon and I try rolling slowly into the gas to accel then it bogs till i give it enough gas then it takes off fine.

THe fuel mixture screws are at 2 1/2 turns and doesnt use much choke at all to get it started

[race2win]

I really think its all in the pilot jet at this point but do not understand why I would need to change this Factory Pro doesnt say anything about maybe needed to make pilot jet changes?? All I can think right now though.

The problem does get worse as the engine gets warmer

[johnnyracer]

Factory pro directions say to get the mains right first, then the mid range(needles) then the idle. They should have given you a troubleshooting guide with the directions. My problems are related to added motor work that I have done and dont have time to work on since i am in the midst of a points chase right now and dont have time to test or dyno. Wish i did. Went back to old set up.and know it works, plus have other issues. Need to know where I am at before I get after it.
If I were u go to 2 rounds on air screw or maybe try a little less float, but make sure your main is correct before u do.

[WAR MACHINE 13]

maybe a combination with the pilot jets and the needles . have you checked syched the carbs ?

[fj1289]

If the problem gets worse when the engine is warmer, it is rich. Sounds like it is at the transition to the needle from the pilot circuit. I'd try dropping the needles a notch (move the clip up one notch).

Like johnnyracer said, need to get the mains right first. If you get the needles right and then swap the mains, you may have to readjust the needles.

[race2win]

thanks for the info. it doesn't take much like last night it was maybe lower 50's here and i almost couldn't feel like hesitation. During the day though mid 80's and the you can really tell. I did go from 2 1/2 turn to 1 1/2 turn on the mixture screws and it seemed to help but the idle kept getting hung up so I just ordered some smaller pilot jets. Thanks again for all the info.

Also when I do to the track I have a small turn down I run for exhaust after the collector, on the street I just run a split on muffler. Will this make a big difference in the main jet and the track?

[johnnyracer]

It sounds like you are rich in that transition, like fj1289 said. Lean the needle one and/ or lean out the float. Cant remember where u are at. Like we said get main correct, then mid, then bottom. They also say not to go less than 2 rounds on air mixture.9 That is how factory wants you to do it! If you change the exhaust it will change the tune up. How you tune it is how you should run it. Factory Pro customer service is very good. Talked to them at length about my situation and very helpful, if u have questions give them a ring also.

[race2win]

Yeah lowered the needle one and it seems to have helped. But after just cruising up and down the street the plugs are still pitch black I have new pilots coming it tomorrow going to try that and see what that does to it. Thanks for the info I might try giving FP a call and see what they say also

[fj1289]

How does the bike act when you blip the throttle at idle? (after it's warmed up!)

If you rev the engine and it slowly returns to idle, you are too rich. If you rev the engine and it drops down below idle speed then comes back up to the correct idle speed, you are too lean. The idle mixture is right when you blip the throttle and the RPMs drop right back to the idle speed.

You also may want to try a new set of plugs - once you've gotten them good and sooty, you may have to go overly lean to burn all the crap back off of them. New plugs will show better. But, unleaded gas doesn't color plugs like leaded gas.

[race2win]

Just going off the top of my head right now I thought when the throttle gets hung up after blirpin the throttle the mixture screw is to lean, which is what happened when I went to 1.5 turns on mixture screw so I opened it back up. Going to throw a new set of plugs in it tonight do some riding see how it goes Ill make sure I throw a update up Thanks for all the advice everybody