Freshly Rebuilt G1 w/90 lbs Compression

[jimdurt]

Well I have been through 2 different piston kits on my G1 and the compression has never been higher than 90#. First piston had too much ring gap. I used my old rings in the new cylinder after careful filing of the ends to meet specifications and still no improvement. I am in the process now of removing the head gasket and lapping the head to the cylinder with grinding compound. I will then use Form-A-Gasket #3 (Aircraft Grade) sealant in place of the gasket. This should increase my compression.

Any other thoughts?

[sho305]

Cut the head they usually don't charge much to do it at an engine shop. Better yet if you can cut the cylinder on the top iirc the piston does not reach the top of the bore? That will raise comp and your ports. I had my head cut, timing advanced, I worked the top of the exhaust port a little, worked over the primary clutch (the old one, I shimmed the spring to take off harder), forget what else but it certainly went far over 20mph on stock tires. Totally stock then no its not going to do that much without larger tires to give more gearing. Mine really screamed at top speed, vibrated kind of funny too lol, I think the secondary was bottomed out it sort of hummed when in overdrive like that.

[jimdurt]

Okay first, what does iirc mean?

Second thanks for the info. I believe my clutch needs work. My cart scream when WOT down the road but low end torque is bad. Primary is engaging too soon. I will shim the stock spring first and grind some weight off the weights.

I have already hit 23mph on stock tires. The blaster pipe helped a lot. Just have to get my low end grunt back.

[BigBlockMan]

Might want to have your original cylinder bored and put a YAMAHA piston and rings in it. I bet money your 20 year old OEM jug is better material and probably better condition then the one you just bought. Not saying your problems are funny but It's stories like this that make me laugh when guys say a clone is same quality as a Honda. Some import parts are ok, Two places you should never scrimp is your motor or you suspension.

[sho305]

iirc, if I recall correctly. I was running G1s when they were pretty new....had 60 of them. (not really mine of course)

[jimdurt]

Where can you buy actual YAMAHA pistons? Everything Carts is where I bought the last two.

[sho305]

Dealer does not have them? Some stuff they are not that expensive on. The one here is http://www.boylansales.com/ They show $58.26 for '83 up piston.

I get some parts from TNT golf, I am sure there are others but will have to ask them who made the parts. The clutch sheave I got at TNT sure looked yamaha but the old one was too trashed to find any marks on it so I don't know. However yamaha might not even supply that clutch it was the old G9 style not the roller.