Im thinking a minor variance in valves... what got me was the statement "no difference in performance" when he changed jets...


If he went 130 to 145, there should have been SOME degree of difference, whether or not it is just a tiny bit, there should be some difference, like we said earlier, popping, back firing, or something with a fat jet...


only other issue I can think would be an internal issue with the carb... I have seen it with a couple tomberlin karts that the carb had a bad casting, causing the buggies to run like dirty diaper! then we swapped out for a carb of a perfectly running buggy, and they were fine! maybe you have a poor valve body in the carb to direct the fuel, or a bad/hanging float (maybe not the float), but something is not allowing enough fuel to reach the chamber! if not an air leak, check your valve lash and spark plug gaps and make sure they are in spec!.,


good luck!!


john

BIGE,

Don't you ever get sick of being right? Lol So the problem was two fold. The intake boot was all jacked up. The O-ring gasket was crushed beyond repair, and there was all kinds of gasket debris on the matting surfaces between the intake on the cylinder head. I cleaned up the mating surfaces with steel wool, and that was that.

the other 10% of the problem was the MRP CDI running too advanced for my buggy. However, the difference between the MRP CDI and the OEM CDI are like the difference between a 150cc and 250cc. No joke, this buggy is like an un-caged animal with the MRP CDI. Because of this, I am willing to live with the remaining 10% and try and compensate with jets. This thing is a blast. I am hooked. Thanks everyone for all your help!

Good for you!!!!

I told you it was'nt right. Those leaks can be a bugger to find as well as restricted flows. Awsome brother

I think I may have got my Neighbor hooked as well. He brought his son over late afternoon yesterday and I let them ride. Didn't see them or the buggy for 20 minutes.

Anyhow, I showed them the new Carter Revo coming out. Boy I wish I could convince the boss (aka wife) to let me get one of those. Well, hopefully I can convince my neighbor to buy one, and then I can ride it.

Convince the neighbor to buy yours because "you really like" fixing them up and this one is all fixed up now, running perfect.

Well i do have the air intake leak because i sprayed carb cleaner at the intake neck and the engine sped up.

Tomatolord

I like the way you think

Seriously though, I have been struggling with this lean condition since the buggy was new. I finally have it under control, but not necessarily resolved. I don’t think either intake boot is real great. Neither the one that came with the buggy or aftermarket one I purchased seem to work very well. I am currently running a #45 pilot and 135 main. The big pilot jet seems to compensate for what little intake leak still remains.

I have a 30mm CV carb on the way. Not sure if I am going to install it right away, now that I have the current setup dialed in.

On a different note, I am very pleased with the Coolster 6250 Dbl. It has been a great buggy thus far. I’m thinking about purchasing a donor 150 kart next Spring and installing a 440cc snowmobile motor. That should be fun.

Have you upgraded your fuel line or is it stock?