I pulled the slides and made sure that the diaphragms are o.k.
When revving it to full throttle, both slides are going wide open. Just like before; idle is great,starts great, but as soon as you approach 1/2 throttle, it will burble and only maintain the current speed. The part that really baffles me is that it seems to rev further with the airbox off.(only slightly better).
WTF. I don't know what else to check, but I'm pulling my CDI off next.

 

Crazyrc
Hopefully you did not over tighten your pilot jet, may want to check.

Definately go back to the stock CDI and be sure all your hoses to your carbs and airfilter are connected correctly and your manifold screws are tight on both your carbs, and your ram air/snorkel to your airfilter is not blocked

Before you install your airfilter, Take a low pressure air gun (5-10 psi) and spray air to middle vent hole (brass colored on 650 prairie) in your carb inlet to purge carb lines. hold head away, gas will purge straight up from adjacent hole. [img]i/expressions/face-icon-small-cool.gif[/img]

 

this may sound dumb but how can you drain the gas on the 02 prairie 650?

 

Disconnect your fuel hose from the shutoff valve near your airfilter and turn on the key.[img]i/expressions/face-icon-small-smile.gif[/img]

 

Any other suggestions...If no one has anything else to try I'm going to have to take it to a dealer. I've tried everything I can think of and I've had no positive results.

 

I know exactly what your talking about, we tried a jet kit on my brothers 400 and had the same problem. went back to stock and still have the problem. Has half the power it did before we touched it. weve had it apart at least 20 times and cant figure it out. I finally gave up on it and told him to go to dealer. Does anyone know? if the floats were bumped and knocked out of adjustment would it cause this? Im out of ideas. crazyrc, if you find the problem keep us posted. I will do the same.

 

I talked to a mechanic this morning and he said to have a look at the tube that the main jet threads into. I've never actually taken it out. He said if it is removable, that you simply push it from the needle side of the carb. The main jet has to be taken out first. I'm going to pull it apart one moe time and see what I can find. He said on some models , the tube is perforated on the sides and could be plugged up. I'll let you know.

THis is just my luck my 29.5's show up and now it doesn't want to run.

 

Thanks, that might be my problem as well. I noticed it seemed like the main jet didnt screw in all the way and didnt feel just right. When I took out the stock jet the tube came out with it. When I put the tube back in it didnt seat all the way.