G2 engine run rough at low speed

[TechBill]

I took my G2 to camping with me over the weekend and it ran great for 3 days then today when driving at low speed ( barely depress gas petal). Engine start acting weird, rpm speed up then drop down and speed up again. But went petal fully pressed down it seem to run fine.

Look like it not able to drive around smoothly at lower speed without jerking the cart. Also when it shut down, it want to crank over one or two more times before stopping. Before engine would shut down instantly when releasing petal


I already tried the mixture screw by screwing all way in. ( was 2 and half turn in) then back out one and half turn out. Does not improve anything


Bill

[TechBill]

when we drive at low speed, it slow, fast, slow, fast, slow etc. Driving jerky etc

Bill

[smallblock450sl]

Might take the primary clutch cap off and check the weights

[TechBill]

Originally Posted by smallblock450sl

Might take the primary clutch cap off and check the weights

Okay, I will go check the weights.

Bad weight can cause engine rpm to act weird at lower speed?

Bill

[TechBill]

I took off the cover and did not see anything that seem broken however I could wiggle the outer clutch (one that cover is screwed onto).

Is it suppose to be able to wiggle loosely by hand or firmed and tight?

I record a video of it on iPhone while it running, I will try to upload the video when I get home tonight since I am Deaf and I hope the video also record sound on it

Bill

[TechBill]

Here a photo and a YouTube video of the primary clutch in action. I put it in neutral and stepped on the petal briefly.

https://www.youtube.com/watch?v=oUHCV7LJSj4


I hope the sound works in the video, I can't tell since I am Deaf and someone could help me out here to determine if my clutch need fixing or it something else that causing this issue.

Thank you
Bill

[TechBill]

I am looking around at prices on clutch in case if the clutch that is bad.

I have a question, must it be replaced with a G2 only clutch or can newer clutch from other Yamaha models fit on a G2 or is there a aftermarket clutch for G2 engine. Would those aftermarket clutch fit on other engine shaft if I decided swap engine in future?

Bill

[smallblock450sl]

Nothing out of the ordinary. Disconect the airbox hose at the carb, run it and tell us if there is any change.

[TechBill]

Originally Posted by smallblock450sl

Nothing out of the ordinary. Disconect the airbox hose at the carb, run it and tell us if there is any change.

So it look like that the clutch is okay? No horrible sound or rattling etc?


Right now it at the campground storage shed which is close to 3 hours drive away.

I thought it wouldn't run at all if the airbox hose is disconnected from the carb since the fuel pump depend on the vacuum from it to operate. I rebuild the fuel pump completely with the new gasket sets and installed a new fuel filter in the tank last month.

When I go back to the campground, I will disconnect the airbox hose, what should I expect when I disconnect it?

Bill

[TechBill]

Can a bad petal switch do this? It felt more like when I drive it at a low speed that it would run then shutdown and run then shutdown causing it to jerk back and forth while driving low speed.

Once I press the petal all the way down, it run normal and seem to drive good.

Bill