G1 drive belt wear symptoms

[Routweiler]

I just purchased a Yamaha G1. It is pretty slow going up hills. Not to the point of being terrible, I just want it to be a little better.

The service manual shows that a new drive belt should measure 1.22" and should be replaced when worn down to 1.06".

Mine measures 1.12". A bit more than half worn out.

My question is this,
Is this enough wear to considerably affect the carts hill climbing torque?

The motor has 120 compression and leaks down to 101-102 after a couple of seconds so not exactly new but not worn completely out either. Other than the hill climbing, it runs pretty good. I have also read here that these carts are notorious for leaking crank seals.

Which(or both) is more likely to do this?

Not sure what symptoms to look for as far as the belt.
Thanks for any advice you can give.

[sho305]

Bad crank seals usually hard starting needs lot of choke to start. It should run ok with that belt but lot of other things can slow it down, one of the clutches not shifting right, check the ramps on the back of the secondary, lube the shaft inside the spring there with lithium spray or other spray grease. The biggest issue is the mufflers plug up with carbon after all these years, I would run a large wire up in the tailpipe and move around see if anything comes out. You can replace them, bonefire them, you can take them loose from the engine so you have a big leak without removing it, then very short test drive see if it does any better on power.

Another issue is if the sheaves (sides of the clutches that belt runs on) get really worn in from the belt they don't shift right and you lose power. Eventually they wear through and tear up the belt or break. Actually a 1.25 wide belt will run better on those, it will take up the space of the worn away metal and it will shift better.

G1 should go up about any hill until it spins, sure it will slow down some but they have good power for a cart.

[Lochlin]

Originally Posted by Routweiler

The motor has 120 compression and leaks down to 101-102 after a couple of seconds.

This leak sounds fishy. That compression should be holding steady pretty much indefinitely without a load on it. That's a pretty good compression drop after a couple of seconds with no load. Add the load of pulling a hill and it will be even more compounded.

If you are running good flat then you fuel draw is good and your crank seals are probably ok. Just one guy's opinion but I think you have a top end issue.

[Spicyunicorn]

Leak down and compression test are different it's probably just the schrader valve in the compression gauge leaking