1984 marathon 2pg has no power

[tirefixer]

I would like more power from my 1984 marathon. Since I bought the cart I have done a complete engine overhaul. I made sure the square hole in the piston is facing the intake side of the cylinder. I installed a new muffler and both the drive and the driven clutches are also new.The cart has the same amount of power in reverse as it does in forward. I have eliminated the governor and the oil injection. I have been using 100 to 1 oil mix. I recently installed a shorter belt. I installed a new carb,gas lines and a rebuild kit in the fuel pump. I have been reading this forum for quite a while. I might try shimming the driven clutch. I have not checked the timing yet so that might be another option. I am running out of ideas. The cart has stock size tires and no lift kit. I am looking for power not top end because I would like to use it around my farm and I take it to swap meets.

[TheGDFP]

Having the head milled is cheap and easy, adds a lot in the middle.
Stock reed cage is restrictive, can be modded.
Larger carb, 88-spec, and pipe zoom things up.

[tirefixer]

I think there is something wrong with one of the stock components because my cart has a hard time getting up hills that aren't very steep. So before I start altering parts I am hoping to find the problem with the stock parts. Today I drove the cart around with the seat off to watch the clutches work. They seem to shift up to high gear very fast and then when you come to a hill they stay up in high gear and the engine bogs down and the cart slows way down. Tomorrow I will pick up some washers for the driven clutch and see if that helps. Compression on the engine is 145lbs. I have a carb from an 88 2pg engine. It didn't run any different with that carb. Thank you for the response. Eventually I will shave the head a little.

[misterpowertools]

How you described the clutch behavior is typical of a stock setup. There are HP clutches available... CPP... Also, the 88 carb without the 88 muffler would tend to run rich... maybe could be adjusted.

[tirefixer]

I put the original carb back on. I do have a comet clutch for the drive clutch. I checked the CPP website and they don't offer any upgrades for the driven clutch on my 1984 marathon. All of their upgrades are for 1989 or newer. Thank you for the info. I am having trouble finding the right size washers that I need to shim the driven clutch. Does anyone know where I can find them? Another thing I might check is my reed valves. I don't know much about reed valves. How will my cart act if they are bad? Maybe they could be the cause of my low power.

[misterpowertools]

You can send CPP your driven clutch for machining... $50 and they make it a 28deg unit which keeps it in lower ratios longer.