G1 not running to well

[rangerroy1]

Just purchased a 1983 G1.( my first cart) My problem is that it would only go about 2 miles an hour and runs like crap. Some one cut the exhaust header and welded on a dirt bike muffler. I pulled the carb off and cleaned it and tried the cart and it still ran like crap.So out came the sawzall and off with the dirt bike pipe. Tried it with the straight pipe and it seemed to help out some but still not running to well. Then I tried it with the air filter removed from the carb and it seems to run better. Can any one tell me what my next step in checking would be, And also how many turns out does the air fuel screw need to be set at. And I also need to know if I need to unhook the oil injection and start running a pre mix and what ratio. Any help would much apprecatied. Thanks

[Mike Mac]

I only have 4 cycle experience, but I believe cutting off the muffler has up set the air fuel ratio. You either need to have the correct muffler on or jet the carburetor up to match the increase in air flow. The air filter canister has to be sealed for air leaks as well. If it leaks air, the air fuel mixture will be off and it will run poorly. If your going to run with both, air cleaner and muffler modified, you need to jet up the main jet in the carb. to get back to the correct air/fuel ratio. The idle mixture screw should be turned out 1 and a half turns as a starting point, then fine tuned from there.

Hope this is a start till the big guys get here with all the experience.

Sorry don't know what the oil mix should be.

[GMB74]

Sounds like you have covered the air inlet and air outlet situation, now we need to look at what happens in between. The engine will run better with the proper exhaust, but should run OK with a wide open pipe. Something else is going on. How much compression does your engine have? It should be a minimum of 100 psi. Is your throttle linkage opening the throttle up all the way? Do you have clean, fresh fuel and a clear fuel filter? Cover the basics first. Is the engine revving up but the buggy not moving very fast? This would be an entirely different situation. Give us some more info and we can help you out.
You do not "need" to remove the oil injection, but let's get you running properly first before we get into that.

[Mike Mac]

Thanks GMB!

[rangerroy1]

I HAVE A CARB REBUILD KIT ON ORDER, SO WHEN IT COMES IN I WILL GET IT PUT ON AND SEE WHAT KIND OF PROBLEMS I HAVE THEN. IN THE MEAN TIME I AM GOING TO TRY A REWELD THE PIPE BACK ON THE FACTORY MUFFLER. tHANKS FOR THE INFO SO FAR.