Runs only when it's choked......

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dlopes

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I just rebuilt my carbs and set my float levels at 1.115" (Morley's advice) and sprayed carb cleaner in EVERY hole to make sure I had zero blockage. She starts up and runs decent with the choke on, but as soon as I take the choke off, she dies. I have tried many adjustments on the air fuel mixture screws (1.5 to 4 turns out) as well as the carb adjustment screws and she still dies. Could it be my float levels or is it something else?
 
Are your carbs sync'd? Is your idle thumb screw set correctly? Did you tighten the carb boost sufficiently? When you rebuild the carbs did you remove each pilot fuel jet for inspection and cleaning?
 
Are your carbs sync'd? Is your idle thumb screw set correctly? Did you tighten the carb boost sufficiently? When you rebuild the carbs did you remove each pilot fuel jet for inspection and cleaning?

How can you sync the carbs when it only runs while choked?

Not sure what the "correct" setting on the thumb screw is, but I did play with it.

Boots are tight.

I removed every part....every part. Plus, all the jets are new. I used 4 new carb rebuild kits.
 
Give it enough choke so it at least idles and then sync. Gradually decrease choke and continue to sync until engine is warm and in sync. Sometimes when removing carbs it causes carbs to be severly out of sync and it won't idle w/o choke. When I put my carbs back on the bike I slowly decrease choke, sync and adjust idle screw at the same time.
 
How can you sync the carbs when it only runs while choked?

Not sure what the "correct" setting on the thumb screw is, but I did play with it.

Boots are tight.

I removed every part....every part. Plus, all the jets are new. I used 4 new carb rebuild kits.

What "New Kits" did you use.... that may be your poblem. If you got those kits off eBay, some of them are crap. I have heard some bad stories about inaccurate jet sizes and what not. I had problems with those on my old V45 too.
 
What "New Kits" did you use.... that may be your poblem. If you got those kits off eBay, some of them are crap. I have heard some bad stories about inaccurate jet sizes and what not. I had problems with those on my old V45 too.

+1 to Jeff - when I read this thread, I thought the same thing - the Keyster carb kits on ebay are not very good

Mike
 
GREAT......yea....I used the kits off of EBAY. Why are they not good?

Some people who used those in the past had bad experiences - kinda just like yours I guess, where bits did not fit properly and bike would not run right.

I looked at those myself when I rebuilt my carbs, but on this advice decided aginst them and ordered just what I needed from Gary @ Mondak Motorsports (OEM Yamaha parts at a great discount for VMF members).

In carbs, everything works at such ultra low tolerances that any sub-par parts will only wreak havoc in the balance of things..

Sorry! :confused2:
 
Some people who used those in the past had bad experiences - kinda just like yours I guess, where bits did not fit properly and bike would not run right.

I looked at those myself when I rebuilt my carbs, but on this advice decided aginst them and ordered just what I needed from Gary @ Mondak Motorsports (OEM Yamaha parts at a great discount for VMF members).

In carbs, everything works at such ultra low tolerances that any sub-par parts will only wreak havoc in the balance of things..

Sorry! :confused2:


Thanks....I'll check out Gary @ Mondak Motorsports.....
 
If you carbs aren't overflowing, your needle/seats are o.k. to keep, and any other gaskets. Sometimes it is cheaper to buy those kits just for some of the o-rings and gaskets, knowing that you will throw away the jets later on. I would talk with Mark "maleko89" and let him know where you live (altitude) and what mods you have done to your bike - i.e air filter, muffler, etc. He should be able to get you pretty close with what jets you will need to get from Gary.
 
The biggest problem I have seen that causes idiling problem are the small pilot jets inside the jet block. The end is so tiny it gets plugged up very easily.

Sean
 
The biggest problem I have seen that causes idiling problem are the small pilot jets inside the jet block. The end is so tiny it gets plugged up very easily.

Sean

Diddo on that. I had done the shotgun fix for my carbs and got carried away with the carb cleaner into holes it shouldn't be sprayed. I ended up with a complete tear down and found the coasting enrichener diaphrams melted down from carb cleaner and redistributed bits from there all throughout the carbs - and the small pilot jets in the jet block were closed off.

Wouldn't run at all unless on full choke.
 
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