I am almost finished with my bike, so far I have replaced shims, rebuilt carbs, replaced hoses, and have adjusted my air:gas screw, yet my bike dies instantly if it goes below 2000 rmps and sputters and coughs a whole bunch when running. any ideas to help me out?

Does it smell like gas? Sounds like it's running rich. We need some more info for a better diagnosis.

Define "rich". Not too sure what that means. But what else would you like to know?  That's all thats all I can think of.

Any time you rebuild carbs and adjust air fuel mixture, there is plenty of room for further adjustment. Rich means there is more fuel in the mixture than needed. Lean is the opposite, too much air in the mixture. Another way to tell if you have a rich mixture is sooty plugs, but I don't think you have ridden it enough for that.

Does you exhaust have a "gassy" smell to it?

As a matter of fact it does, so should I screw the air/fuel screw in futher?

Tightening the screw leans the mixture, so it's a good place to start.

Keep in mind you have changed/adjusted/replaced a lot of things at once so it's harder to diagnose a problem. I would do the carbs first, ride it and observe. If o.k. I'd do the valves, ride it and observe, etc.

Start with the screw and see what happens. Other possible problems could be valves adjusted incorrectly, something missing or replaced wrong in the carbs etc.

Quote from: SonsaFrantic on March 09, 2010, 03:48:14 PM
I am almost finished with my bike, so far I have replaced shims, rebuilt carbs, replaced hoses, and have adjusted my air:gas screw, yet my bike dies instantly if it goes below 2000 rmps and sputters and coughs a whole bunch when running. any ideas to help me out?

your no where near finished with your bike if you dont have pics posted on here. hell you dont even have a bike without pics.

Lol sorry but I dont really have anything to take pics with..... But I'll be tinkering with the screws for a while, then move to the valves... thanks Ghost

Quote from: SonsaFrantic on March 11, 2010, 03:47:18 PM
Lol sorry but I dont really have anything to take pics with..... But I'll be tinkering with the screws for a while, then move to the valves... thanks Ghost

BTW, did you rejet? Add exhaust or K&N? If not and your stock, i believe 1.5 turns out is about right.

Just a thought. Are the pilot and midrange jets in the correct places?