Low end vibration on 150cc GY6

Posts: 127

My 150b engine vibrates excessively on the low end and runs smoothly at higher rpms. Could this be something loose or a bad roller in the variator? I just changed the rollers at the end of last season, so they have little hours on them. If not the variator, what else could this be?

Posts: 6278

How low rpm are you talking about? Idle?

Posts: 29

im having the same problem, but what mine is is the exhaust mount.

On the side of my CVT cover is a shaft (dunno its purpose) but it has a mount that is bolted on (a clamp style that squeezes on) with a hole in the end to hold the exhaust bolt. Well, it seem that I cant get that mount deal tight enough so it rattles real bad at lower RPMs. I thought it was the pipe hitting the cvt cover at 1st, then checked to make sure it wasnt a roller, only to find it is the little mount deal. Once Im at speed, I cant hear it, may just be the engine, or it may have stopped at that point, but it is very annoying at low rpms. I am going to put some type of new clamp, or something to shield it from the cover, but you may look there!

Posts: 1869

The shaft out of your CVT cover is the kick starter. You can remove that assembly and replace it with a long bolt to stop the rattle.

Posts: 9

PGHRUBY,
You say you can REMOVE the kick starter without consequence on this engine? Does that mean the whole assembly: post, gear, spring??? See photo.

SECESH TIM

Posts: 1869

There are many pieces to the kick starter. The gear behind the variator on the same shaft should stay, but the rest of the pieces can be removed.

You would install a bolt with head inside the cover held in place with a nut. Two additional nuts would hold your exhaust hanger.

I am responding on my phone, so I cannot provide a link to that thread or view your attachment.

Posts: 127

I don't believe the vibration is coming from the kick starter/exhaust hanger on my engine. I plan on taking the cover off the cvt and removing the the variator and making sure all is intact. If all looks good there what else could it be? By the way, low end for me is when you first give it gas to around 5mph. When you get going faster than that the vibration goes away. When you get back to the lower speed, the vibration returns.

Posts: 127

Thanks Rustyking, you were right! The vibration was in fact coming from the exhaust hanger vibrating against the cvt cover at low rpm. I took off the cvt cover and removed all the kickstart internals, used a 4.5" long 1/2" threaded bolt and with nuts, flat washers and lock washers put in a more substantial and STABLE hanger attached to the cvt cover. No more low end vibration! One more issue solved. Never did figure out why my lights stopped working though. Runs good otherwise, at least for today.

Posts: 1869

Make sure you reattached the the ground strap to the CVT cover. The engine will run, but accessories and lights will not without this properly connected.

Posts: 127

Grounds reattached. All accessories except the lights work (turn signals and horn). FYI, this has been an ongoing/unsolved issue on my buggy. I have already replaced the stator and flywheel (upgraded 6 pole) and regulator trying to get the lights working. I can't find any lose wires, but there is no power to the light switch up front. Any other ideas? Just stopped working one night.