Revs out decent, spitting on low throttle

[ThrottleJunky]

The carbs have been completely rebuilt, and are clean as a whistle. The floats are adjusted, and I verified they are no longer leaking into the airbox. I've got a hesitation and popping coming out of the pipes off idle. Does this sound like a lean issue? The air/fuel screws are all set at 1 1/2 turns out as my starting point. I know I need to tune them and sync them, but I wanted to get it out on the highway first, and run it a bit.

[ThrottleJunky]

This is really bizarre. It's been a while since I worked on the bike, and last time I ran it for a moment, the leaking fuel thing was remedied. After running it today, I had some fuel dripping out of the airbox. I pulled the airbox off, and it looks like it's coming out of the second carb from the left side. The seat has a new o-ring, and the floats were adjusted and perfectly operable, sealing soundly when I blew into the fuel line. I tapped on the float bowl, and it seems to have stopped for now. Hmmm.

[bikerphil]

Sometimes a float will get stuck and one tap will fix it. If you are running lean, checking the plug color will tell you. Out of sync carbs will cause your symtoms, best off syncing them and go from there.

[DGXSER]

the tapping probably did fix it as Phil says (he is a very smart guy )

I would agree, take it out and get it warmed up good, then synch the carbs, run a bit more. Check plugs for color and adjust screws from there. If you have a colortune they are great for getting you pretty close on mixture screw setting. But I always recheck plug color and adjust for that.

[petejw]

if the fuel was leaking into the air box,
it will run the way u described,

if uve fixed the leak (possibly had a little crap
holding the needle open from the seat) are u running fuel filters?
and its still running like crap then you could
be running lean on the lean side.

also clean the plugs wont hurt if the cylinder was flooded.
and as the other boys have said, sync and adj mixture screws.

[DiverRay]

The only thing NOT stated is the floats MAY be "hanging up" on the gasket or bowel wall. I always check to make sure the floats will clear both. I HAVE had to trim gaskets to keep them from hanging up the bowels.

[ManagerMike]

The only thing NOT stated is the floats MAY be "hanging up" on the gasket or bowel wall. I always check to make sure the floats will clear both. I HAVE had to trim gaskets to keep them from hanging up the bowels.

Don't you just hate it when your "bowels" get hung up!

[ThrottleJunky]

Thanks for the responses guys. As you may know, I've had these carbs off 4 times now. The thing is, they are immaculate inside, and I'm really stumped as to why the fuel was leaking. If it was a sticky float, it would have to be quite stuck to where the fuel couldn't lift and "float" it so it could close, which seems difficult. With the bowls off, they were perfectly operational. I tipped the carbs back and forth to make sure the floats opened and closed smoothly, and blew into both fuel lines to make sure the seats worked great. This is really annoying in that I'm sure I've got a little fuel in my oil even though the level isn't higher.

I think I'm going to break down and buy a carb synchronizer. Anybody know anything about the Motion Pro unit?

[petejw]

it doesnt take much for a bit of gunk
or something else to hold it open, if youve
blown into the inlets with the bowls both on and off
and the needles have seated,
then it could b sum muck in the fuel line, t
hats y i asked if u have fuel filter/s fitted, they
help a lot.

[cywelchjr]

Don't you just hate it when your "bowels" get hung up!

It's even worse when things get hung up on the bowel walls.

[crazy steve]

Don't you just hate it when your "bowels" get hung up!

What's even worse is if your gasket needs 'trimming'...

[natemoen]

I think I'm going to break down and buy a carb synchronizer. Anybody know anything about the Motion Pro unit?

I would buy the carbtune over the motionpro unit. I have used both and the carbtune is way easier to use and more compact. Little more expensive but I say well worth it! Here is the website, you can also get a colortune plug with it is you want.

http://www.carbtune.co.uk/

[bikerphil]

Don't fprget to check for vacuum leaks. Sometimes it's as simple as a cracked cap on the intake boot.

[ThrottleJunky]

I would buy the carbtune over the motionpro unit. I have used both and the carbtune is way easier to use and more compact. Little more expensive but I say well worth it! Here is the website, you can also get a colortune plug with it is you want.

http://www.carbtune.co.uk/

I seem to remember reading somewhere that it can take months to receive. Is this the case? If so, I can't wait that long. I need to get this thing running well in less time than that.

[DGXSER]

Couple ideas on the floats, as others have stated, it does not take much to hang up one of the floats. I always trim the gaskets even with the float bowl on the inside lip, no gasket overhanging to catch the float.

As Pete stated, it does not take much to hold the valve open. At first I tried automotive fuel line with the soft rubber inner liner. When I was putting the line on the fuel Ts the barbs on the Ts would shred little pieces of that rubber off. And I had a leaking float valve over and over and over, but different one each time. They passed every test great until I put them on the bike. Once I finally changed out to vinyl tubing (Lawn mower fuel line from Home Depot), the valves sealed great.