After it is warmed up.

[ddoonnaalldd]

Hi! New to this forum, and this is my first tread.
I have a 1978 GS750E.
Just had the carbs synced and jetted.
Problem as best I can describe is-
Bike starts great, let it warm up a few minutes, Go riding everything is good. After about 15/20 minutes the bike gives me a lot of trouble from a stop, wants to stall. Once you get in to it, it's fine. When I come to a stop and rev the engine on the way down it almost stall's. Could this be the head gasket starting to go bad?
I ask because when the guy who put in the valve cover gasket was cleaning the engine it stalled when he sprayed degreaser in that area.

[Dave8338]

Have you pulled the plugs to have a look? Sounds like the bike was over jetted from what you describe ie. getting too much fuel.

[doctorgonzo]

Yeah, if I'm remembering correctly idle rising when warm is lean, idle dropping is rich.

[TheCafeKid]

Depending too... a rich pilot setting will cause the idle to drop below desired RPM on a blip...but then it will slowly, if left sitting, rise to above desired RPM.... "Signing off" between shifts, or upon slowing to a stop is a sign of richness..

[chef1366]

If he was spraying anywhere the intake you have a leak.

[Steve]

What mods have been done to the bike that required the carbs to be "jetted"?

.

[ddoonnaalldd]

The mods that were done- 4 into 1, and I'm told it has carbs from a Kawasaki. When I come to a stop it does idle fine. If I twist the throttle slowly (at a stop) it revs up fine and revs down fine. If I twist a bit faster it will bog a bit, but still rev up, and when it revs down it will almost die but will regain idle. It does none of this when I first start riding, only after about 15 minutes of riding. Could it be over heating?

Sorry it took so long to respond.

[Steve]

Not necessarily overheating, but I wonder what carbs were used from a Kaw?

Not saying that they won't work, but there are differences in the carbs from one make to another that make them work differently.

Since they are different carbs, any jetting suggestions you receive here might not work.
The overwhelming majority of us still have stock carbs, so we know what works with them.
When you start throwing in some unknown stuff, all bets are off.

.

[Larry D]

Can you post up some pics of the carbs ?

[ddoonnaalldd]

Not necessarily overheating, but I wonder what carbs were used from a Kaw?

Not saying that they won't work, but there are differences in the carbs from one make to another that make them work differently.

Since they are different carbs, any jetting suggestions you receive here might not work.
The overwhelming majority of us still have stock carbs, so we know what works with them.
When you start throwing in some unknown stuff, all bets are off.

.

They are Mikuni carbs, I thought they were original but a trained eye told me other wise. I would love to but back original carbs but wouldn't know were to begin with that. The bike does run good once you get her rolling

[Larry D]

Never trust anyone's eyes but your own.

[ddoonnaalldd]

Can you post up some pics of the carbs ?

I will post some pics, it won't be till Saturday, I am away from home.