After I have been riding for a while (about 20-30 mins) and I put the bike in neutral or even when I just pull the clutch in the engine starts to slowly rev up until I let the clutch out and load the engine again. Starting at low idle, if you start counting to 20 by the time you hit 20 it is revving very high. I don't know what it is. I've pressure lubed the throttle cable twice and it works like hot butter. There is nothing in the carb slide that's catching. The only thing I have done lately is install new reeds and a reed spacer. My idle screw is backed out 1 turn from closed. Any help here, I am puzzled. I am probably overlooking something simple. Thanks!

 

Could the reeds be set loosely and injecting more fuel over time like a runaway locomotive? Or... could the spring inside of throttle slide on the carb be a little weak? I don't know, I am just thinking out loud here.

 

I was thinking that myself! Good idea. That's the only thing that I have changed in the fuel mixture system. I even swapped in another carb and it does the same thing! Anymore ideas, anybody?

 

Could be too much air...like a leak. Check all connections. Be sure to tighten the cap on the carb, if it is lose it will make it rev like you said.

 

Have you tried to adjust the idle screw under the seat yet? Have you loosened up your throttle cable alittle to see if that helps? Do all this while it is at fast idle so you can tell the effects. You might also have an air leak some where.

 

Where is the idle screw under the seat?

I switched carbs and it does the same thing!

Where else could I have a leak?

 

Did it start doing this after you changed the reeds? If so, has it backfired hard since changing the reeds?

Check the clamps on the hoses going into and out of the carb. Make sure the rubber hasn't been torn and it is getting a good seal.

Have you modified you airbox any? Is your jetting right? ...just some suggestions.

 

As a matter of fact, after changing the reeds we went out riding after about an hour of riding it backfired for the first time ever. Then I started noticing that the idle was creaping up!! What is it!!

My airbox has 6 -- 3/4 inch holes in it. With the new reeds and reed spacer, should I plug the holes back up?

 

A couple of suggestions: I have heard of a backfire melting or harming the reeds. You may want to check them. If they're ok, you might try covering the air holes in your box lid. Or at least put in those small circle filters. My brother's Blaster was doing the same thing. He covered the six holes in the top of his box and it stopped the fast idle. Good luck.

 

I agree with MDP49, it does sound like an air leak.... or lean condition. My first though would be around the manifold and carb area since you were just working to change reeds. Also, did you change jetting after installing the reeds or leave the jetting alone? Might need to be fattened up (larger jets).

Rude Dog