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I bought the pipes...............bought the Jet kit..............Did everything they said (and more) and I cant get the thing running right. I tried every situation imaginable. (Stock Pins/New Jets.......Stock Jets/New pins......Every combo of Jets/new pins)

Every time i fo this the carb has got to come out, so you can imagine how pissed one would get.

Here are the items I have, Bike is a 2001 and it only has 2500 miles. Bike ran great when stock, and ok w/out jets (only exhaust). Once I put the jets in I get alot of bogging down and a rough hesitation while cruising at 55 or so.

Part # BLV92-1274

Cobra Streetrod Slashdown Exhaust for Spirit 750 (01-Up)

The best combo that the bike ran was w/Stock jets and new pins set at 3rd slot. Still a slight hesitation. Any help here would be great, does anyone have this situation or at least this bike that could give me some insight?

Are you still using the stock air filter?

Just what I was going to ask Minty

This is a stage one jet kit. Designed for tha addition of exhaust pipes, with the useof the stock air box, and stock filter.

So the answer is yes. I'm borderline going in to get this thing Dyno tuned. Not something I thought I would have to do, or wanted to do.

Any thoughts now?

Is the air filter CLEAN?

Bogging down seems to indicate too much fuel and not enough air in the mixture, so take a very good look at your air intake system before throwing some bucks at a dyno run.

Also, I have heard that some jet kits that run stock airbox and filter require some drilling to open the box up slightly. If the bike was running super-lean I could understand just putting in bigger jets to solve the problem but more juice and no more air could be your problem.

I hear ya man, and i agree w/your thought process. But after taking the Carb out for what seems like the 50th time, I dont even put the airbox/filter on the bike when I take it on the road to fine tune it. So air I dont feel is the issue here.

I agree it seems like to much fuel, or not a comstant pressure of fuel, bit I dont feel its the breathing of the carb thats making it do this.

All I know is that its pissing me off.

any chance it could be a weak spark? I changed the plugs, and the wires and all that other stuff is no more that 2 yrs old. Either way I doubt it, It ran perfect w/the stock jets w/the after market exhaust (except for the backfiring). As soon as I cnaged the jets it got all whacked out

Did you adjust your air/fuel mixture screw to suit the new jetting?

they say to lightly seat the mixture screws and back em out 3 turns for the new jets/pipes. I do this and find that 3 3/4 seem toi be better............BUT........................that oes nothing for the hesitation.

I mean I went out riding w/ a screw driver in my pocket and tried everything. I adjusted every chance i could and still cant stop it.

You WILL NOT get the stumble out of it while running it WITHOUT the air box. Please put the air cleaner assy. back on before you try and tweak it's running problem. When doing services on these bikes at the shop and synchronizing the carbs with the air filter cover off, the bike stumbles off idle.
Usually after the mixture screw is turned out past three turns, it's adjustment is done. Maybe go bigger on the idle jet.
I don't see why you would need to do being in New York.
I have done many of these and have never had a problem using the recommended settings.
How are the diaphrams, are they pinched?
Have you had the carbs synch'd? Taking them out as many times as you say you have can easily and probably have changed the setting.
Do not modify your airbox to try to get it to work. There is no need for that. The jet kit you have does not require any mods.
I will look tomorrow when I get to work and look through my notes on jetting for this model. I use Dyno-Jet which I think should be the same.
I hope my memory holds up, if it does, I will post with my settings.