Road trouble

[Anonymous]

I have a 79 GS750L that will idle just fine,give immediate throttle response, and run just great---until I put it in gear and try to ride. Then it will miss, sputter, and act like the gas has to catch-up to the throttle. What do I need to do?

[Anonymous]

Re: Road trouble

I have a 79 GS750L that will idle just fine,give immediate throttle response, and run just great---until I put it in gear and try to ride. Then it will miss, sputter, and act like the gas has to catch-up to the throttle. What do I need to do?

does it happen in second gear or other gears as well??

[Anonymous]

This seems to occur in all gears.

[Anonymous]

This seems to occur in all gears.

take out your plugs and tell us what color they are

[Anonymous]

Plugs 1-2-4 are dry-sooty black and I clean them often. I have tried to adjust the air-screws and replaced the air filter with a k&n unit. Because of the running(riding) problem there has been alot of "idle" time on this bike and not alot of riding.

[Anonymous]

Plugs 1-2-4 are dry-sooty black and I clean them often. I have tried to adjust the air-screws and replaced the air filter with a k&n unit. Because of the running(riding) problem there has been alot of "idle" time on this bike and not alot of riding.

Did you lose plug #3 and ir is starting to sound like your spark is bad

[focus frenzy]

one remote possibility, a bad ground! with the bike still and in neutral it gets enough ground through the transmission gears, but moving the oil film on the gears prevent it from grounding through them, check the point where the ground wires attach to the frame, clean and make sure they are tight.
I have seen this once before, it is rare but happens

[Anonymous]

I checked and cleaned all of the plugs today. All of them were sparking just fine, and plug 3 is showing signs of use. I simply assumed the air screw was set just right for the #3 carb.

[Anonymous]

Listen to leon. this smells lie an electrical problem to me. Just a feeling
after that the carb freaks will have to jump in

[argonsagas]

I think in your '79 you have standard ignition....what you are describing could be caused either by bad condensors or just maybe by wrongly spaced points or even a weak coil...but the latter would mean TWO weak coils, so I would look elsewhere.

As you said it runs fine with no load, but poorly under load, by all means check the points, but I would lean towards replacing the condensors.

(Note....it does not matter when you installed them....reality is that sometimes condensors last minutes, instead of months or years.)

[Anonymous]

I replaced both of the coils(a month ago),and this morning both condensors and both points. I checked and rechecked the points gap and the setting is fine. I checked the ground wire(at the battery case I assume, it was the only ground wire I found) and it seemed to be fine as well. Some more tinkering with the air screws as well as the idle seemed to help some but the onset of night will delay anymore play until tomorrow.

[Anonymous]

Taking a tip from another post I let the bike run a few minutes then checked the exhaust and found I could fully grab the third pipe while the other three were too hot to touch. What do I need to do? The plug is firing and just to check I swapped it out with another and the third pipe was still cool while the fourth ran hot after the plug swap.

[Anonymous]

Taking a tip from another post I let the bike run a few minutes then checked the exhaust and found I could fully grab the third pipe while the other three were too hot to touch. What do I need to do? The plug is firing and just to check I swapped it out with another and the third pipe was still cool while the fourth ran hot after the plug swap.

seems like you have ruled out the electrical theory. Now see if the carb to the cold cylinder is getting fuel or if possibly it is clogged internally and also if the float level may be stopping gas from getting to that carb. Here is a thought. If it is not firing number three then that plug should be wet if it is getting gas.

[Anonymous]

Is there a way to check the fuel intake on the carb without having to remove the whole bank and disassemble the whole unit? I hope!

[Anonymous]

Dead Cylinder

Don't overlook the possibility that the #3 plug wire boot could be jumping fire to the head. This is extremely hard to see in the daylight. I had the same deal with 1 cold cylinder and 3 hot. I found it after starting it after dark one night.