Got her running, but

[prez342]

I'm the guy that had fuel leaking from the air inlets on the carbs on my 79 xs. I did the bread stick thing, The seafoam thing, and also adjusted the floats (only by eye so not perfect). Carbs were rebuilt last year.
It starts and will run when the choke is out all the way but when given gas it will die. Did I possibly adjust the floats so not enough fuel will get in? It will rev up to 4000 with the choke out. Also when I put the carbs back in I did not tightn the carbs onto the boots, could there be a air leak? I did have it running with the choke on the halfway point with white smoke comming from the 1 and 2 carb exhaust.
Help I just want to ride this one owner bike.
Rich

[DGXSER]

I certainly understand your wanting to get out and ride!! However, you really need to slow down and do few things to a little more detail.

Start by getting a metric ruler at least and making a gage to check float heights. Yes, really, you need to open the carbs back up and get that set correctly and evenly.

While you have the carbs off and opened up, CLEAN THEM. Take each part out and soak it, scrub it with a soft toothbrush, blow carb cleaner through all the holes and openings.

Then, yes, you NEED to tighten the clamps holding the carbs to the boots. Letting the enginge suck air in here instead of through the carbs will cause it to run lean, thus the white smoke. Do that long enough and you will have missing sections of your pistons known as holes in them!! This is a BAD thing!! They really do a poor job of creating compression when they have holes in them. Your rings will struggle ALOT to keep up then.

After you get these things accomplished. You NEED to synchronize the carbs. It will make a difference. Even if you just get one gage and build the PVC plenum in the tech tips and just move the one tube from carb to carb you can get pretty close.

[XJOK2PLAY]

[Quote: previously posted by DGXSER "Do that long enough and you will have missing sections of your pistons known as holes in them!! This is a BAD thing!! They really do a poor job of creating compression when they have holes in them. Your rings will struggle ALOT to keep up then."


This is true!! (BUT TOO FUNNY, DON... LMAO...)

[tarzan]

Floats cant be set by "eye"

Sure you can try and get them to look level with the mating surface,but you don't have a very wide margin of error with float height.Too high she floods,too low she pops and farts.
Also,who rebuilt these carbs last year?Have you seen it run good?
If no to these two questions then I would recommend you remove them(you have to anyway to set the floats) then clean them thoroughly and inspect all jets,orifices,needles,seats,diaphragms,etc.
There are lots of great threads here to guide you.
A couple of tips,1.dont soak carb bodies in cleaner unless you can leave the throttle shaft above the fluid,there are plastic bushings in there.
And do one carb at atime so you don't mix parts between carbs and you can look at another carb if you forget where something goes.
Good luck and have fun.Hope you get her going soon.
Rick

[petejw]

You might also want to check and see
that there arent any mixture screw tips
broken off, that can cause the troubles your describing.

[prez342]

Sure you can try and get them to look level with the mating surface,but you don't have a very wide margin of error with float height.Too high she floods,too low she pops and farts.
Also,who rebuilt these carbs last year?Have you seen it run good?
If no to these two questions then I would recommend you remove them(you have to anyway to set the floats) then clean them thoroughly and inspect all jets,orifices,needles,seats,diaphragms,etc.
There are lots of great threads here to guide you.
A couple of tips,1.dont soak carb bodies in cleaner unless you can leave the throttle shaft above the fluid,there are plastic bushings in there.
And do one carb at atime so you don't mix parts between carbs and you can look at another carb if you forget where something goes.
Good luck and have fun.Hope you get her going soon.
Rick

I rebuilt them last year and she did run fine for a year. Not perfect syncro though. I used the seafoam trick to see if that would work, something might have caught up inside. I will clean them out though.
When adjusting the float height is it measured with the gasket in or not? and what is the best way to bend the tang?

[tarzan]

Floats are measured without gasket.
I bend the tang with a small screw driver.Just be careful not to put any pressure on the needle while doing it.

[trbig]

Gasket off.... and I use needle nosed pliars on the metal piece the float attaches to, not the little tang that actually goes against the float needle. It's doubtfull that both floats are level anyway, so just bending the tang isn't going to get you where you need.


And with that... Tarzan becomes the newest Guru!!


Tod

[CatatonicBug]

It's doubtfull that both floats are level anyway, so just bending the tang isn't going to get you where you need.

That's a good point! I never thought of that. The 2 floats on each carb are not necessarily both even, and cannot be treated as a "set". You have to adjust them individually.

Congrats Tarzan!