77 gs750 Carbs are blowing air out?

[Guest]

So I rejected my carbs last night since I have straight pipes and I'm running pods, put in 117.5 from 105. Put it back on and tried to start the bike and it wasn't starting so a buddy tried to hit it with some ether quick to see if it just wasn't getting fuel. When he sprayed it, it sucked in some but blew a lot back. He then put his hand over the carbs and pulled away with gas on his hand. I'm guessing this is a timing issue but any other ideas as to why it would do that? Also the number two carb is pouring gas out the over flow tube, can only assume that's a float issue.

[hannibal]

Was it running before rejetting?

As for #2, check the float height. If lowering the fuel height doesn't stop the overflowing, you may need to chexk the float valve needles.

[jdvorchak]

I've seen this before and sometimes it's the spark plug wires on the wrong spark plugs. 1 and 4 run off of one coil and 2 and 3 the other.

Putting your hand on the carb that IS working will wet you hand. That sometimes happens.

[R3lease1t]

It would run, but it was really hard to start. I replaced the piston rings this winter and have been fighting it ever since to get it to start and run like it should.

I rebuilt part of the carbs earlier too but got the wrong size mains, I wonder if the pilots I replaced are smaller than what I had before as well. When I put the new float valve needles in they didn't even raise the floats so I put the old ones back in. Might need to put the new ones in and adjust the float height instead.

[R3lease1t]

I checked my plug wires a couple times when I put them back on, they are on the correct plugs. It would run with the old jets in, just really hard to start. Can't imagine it would run if I had the wires switched

[2BRacing]

A faulty petcock could be dumping gas down the vacuum line to number 2 carb.

[R3lease1t]

A faulty petcock could be dumping gas down the vacuum line to number 2 carb.

I replaced some parts on the petcock last year like the seals and diaphragm. Shouldn't be bad. I'll look into it though.

[jdvorchak]

I checked my plug wires a couple times when I put them back on, they are on the correct plugs. It would run with the old jets in, just really hard to start. Can't imagine it would run if I had the wires switched

trust me it will run with 3 and 4 swapped... I've made that mistake before..LOL

[phydeauxmutt]

So I rejected my carbs last night since I have straight pipes and I'm running pods, ...

Sounds like your carbs are "rejecting" your straight pipes. And rightfully so.

... a buddy tried to hit it with some ether quick to see if it just wasn't getting fuel. ...

One of the BEST ways to blow up an engine.

I'm guessing this is a timing issue but any other ideas as to why it would do that?

It IS a timing issue, but not an electrical timing issue. Sounds like the valves are in need of adjustment, which means that they are opening early and closing late.

I rebuilt part of the carbs earlier ...

Why only "part of the carbs"? If you go through the effort to do some of them, why not the rest?

A faulty petcock could be dumping gas down the vacuum line to number 2 carb.

I could understand that if he had a vacuum line to the #2 carb.
He has VM carbs, which have the vaccum line on #3.