carbs won't rev up unless choke is on.

[toymechanic.]

Cleaned and rebuilt carbs and the engine won't rev up after it is warm unless the choke is on. I have screwed the air mixture screws out and it is getting better, but they are out now about 5 or 6 rounds. Any ideas what the problem may be? Are my idle jets too small maybe. I soaked the carbs in Berrymans over night! Then spray them with carb cleaner in a spray can. So i am pretty confident that they are clean. Oh yeah let me mension I added a K&N air cleaner but it has stock exhaust! I have ridden for 57 miles and in order to take off from a stop the choke has to be on! Once it is under way it is fine with the choke off. It has 7785 original miles on it.

Thanks in advance!

Gary

[tconroy]

do you stil have the stock airbox? You might try putting it back on and see what happens

[SqDancerLynn1]

If you put K&N filters on you are running way too lean Their is not enough adjustment in the mixture screws to make up the difference YOU need to put bigger main jets in the carb Raise the needle at least 1 notch & try a 125 main jet

[toymechanic.]

do you stil have the stock airbox? You might try putting it back on and see what happens

I still used the stock air box. I just put a K&N oem replacement in the stock air box! SO even with this I would need a bigger main jet?

[tconroy]

what about your adle adjusment screw?Have you checked for leaks around your intake boots.Will it idle smoothly?Did you set your floats properly?

[toymechanic.]

what about your adle adjusment screw?Have you checked for leaks around your intake boots.Will it idle smoothly?Did you set your floats properly?

As I mensioned before the Idle adjustment screws are 5 or 6 turns out and it was getting better the farther I screwed them out. I did not check for cracks on the boots when the carbs were off!

[tconroy]

Idle adjustment screw located in the back inbetween the carbs,not the air adjustment screws.Did you bench sinc the carbs when you had them off?check for leaks with wd40 around the intake boots and air chamber side of carbs also.You might have a cracked boot or bad o-rings in the intake.

[toymechanic.]

Idle adjustment screw located in the back inbetween the carbs,not the air adjustment screws.Did you bench sinc the carbs when you had them off?check for leaks with wd40 around the intake boots and air chamber side of carbs also.You might have a cracked boot or bad o-rings in the intake.

The boots are fine I just removed the carbs and check the boots.

I sychronized the carbs with a mecury balancer. Idle adjustment screw? do you mean the little knob between carbs two and three?

[toymechanic.]

Oh yeah BTW it idles smoothly!

[toymechanic.]

So with the dead spot between 1500 and 4000 RPMs. Does this all mean I need a bigger main jet or a bigger pilot jet. It doesnot cut out on top end. I feel the floats are set right, the idle is smooth, The passage ways are clean, and with the mixture screws 6 to 7 turns from seated is shimming the jet needle up going to solve the problem or do I need a bigger jet?

[jgordon]

So with the dead spot between 1500 and 4000 RPMs. Does this all mean I need a bigger main jet or a bigger pilot jet. It doesnot cut out on top end. I feel the floats are set right, the idle is smooth, The passage ways are clean, and with the mixture screws 6 to 7 turns from seated is shimming the jet needle up going to solve the problem or do I need a bigger jet?

With your air screws out so far it means you need...

Bigger pilot jet ( probably a 47.5 )
I would raise the needle 2 notches or shim up the equivalent
Probably around a 122.5 or 125 main

This depends on where you motor is at. Cam timing and such can change the requirements for your motor.

These are just suggestions. Jetting can get quite expensive if you have to keep buying jets as you probably already know.

[toymechanic.]

So with the dead spot between 1500 and 4000 RPMs. Does this all mean I need a bigger main jet or a bigger pilot jet. It doesnot cut out on top end. I feel the floats are set right, the idle is smooth, The passage ways are clean, and with the mixture screws 6 to 7 turns from seated is shimming the jet needle up going to solve the problem or do I need a bigger jet?

With your air screws out so far it means you need...

Bigger pilot jet ( probably a 47.5 )
I would raise the needle 2 notches or shim up the equivalent
Probably around a 122.5 or 125 main

This depends on where you motor is at. Cam timing and such can change the requirements for your motor.

These are just suggestions. Jetting can get quite expensive if you have to keep buying jets as you probably already know.

Jgordon,

My whole bike is stock with only 7785 miles on it the camshaft timing is as it was from the factory.

Do you really think I need to shim the jet needle and put bigger main jets in than the 115 it came with?

Gary

[hungryman]

You adjust the main with WOT runs. Once you get that, then you can tinker with the needle adjustment. If I remember correctly, Mikuni and a few other sites detail this procedure.

It sounds like you need to raise the needle a bit for sure.

[ccratin]

You shouldn't need a rejet. You should pull those carb intake boots and replace the o'rings. You may well be getting too much air. I didn't see if you have done a carb synch, but that's important. Do you have a better description of why you rebuilt the carbs? What was happening before? Did you ensure that you blew out all passages in the carbs and that they were clear? It often takes a small piece of wire to clean out everything. Soaking doesn't always get it all. You have to make sure that pilot circuit is totally clear and that the pickup hole is clear along with the rest of the circuit. The K&N stock replacement shouldn't require a major rejet if everything is as it was from the factory.

[toymechanic.]

You shouldn't need a rejet. You should pull those carb intake boots and replace the o'rings. You may well be getting too much air. I didn't see if you have done a carb synch, but that's important. Do you have a better description of why you rebuilt the carbs? What was happening before? Did you ensure that you blew out all passages in the carbs and that they were clear? It often takes a small piece of wire to clean out everything. Soaking doesn't always get it all. You have to make sure that pilot circuit is totally clear and that the pickup hole is clear along with the rest of the circuit. The K&N stock replacement shouldn't require a major rejet if everything is as it was from the factory.

I bought it on 10/01/05 and it only had 7785 miles, so that told me it sat allot and I right off the bat took them apart and soaked them. I beleive 100% that the passages way are clear. I'm going to replaces the K&L pilot jet from the kit and install the original factory ones because the K&L have a .135 of an in ch and the factory ones have a .0145 of an inch. wish me luck.

Gary