I have installed a new 30mm pumper carb on my HH250 last week and tuned it in, the buggy was running perfect and getting a top speed of 46.5mph. The engine was running smooth with no backfire spitting or lag.

Today I was just going over a few things and noticed my manifold to carb was not done up tight, I tightened it and tested the buggy, now I only get to 43.5mph and the buggy spits and farts when I back off from WOT.

I assume when the manifold was leaking it was sucking in air and now that I have stopped the leak there will be less air getting into the engine.

What do you guys think?

Would it now be running too rich?

Thanks

might have to drop down a jet size

Probly. You probly will drop a jet size or so. Your pumper can supply more fuel that a stoker which means you can go smaller on the jet

Your to fast Eric

[Your to fast Eric [/quote]

thats what she said

Thanks guys, just what I thought.

I just changed the main jet from a 145 to a 140 and the buggy doesn't seem to be spitting anywhere near as much, may have to put in a 137.5 main jet (will try this next week as it doesn't seem perfect like it was when the manifold was leaking).

My top speed didn't change much and it seems as if it wants to go faster but can't, at top speed it has a high pitch noise (any ideas?) and sounds like it is hitting a rev limit. It didn't do this when the manifold was leaking and I got more speed. Maybe I should allow the manifold to leak (haha).

I assume it is the stock CDI that is rev limiting the buggy, but way wasn't it doing this when the manifold was leaking?

I will be getting a new adjustable CDI next week and will give it a go.

I wil be starting the CVT upgrade next week too.

You may be to big still. To much fuel will slow you down and wash the rings if not carefull. Look at your pilot as well being a pumper. I'm not sure how much extra is to be gained out of these carbs. I replaced mine more for throtle responce than speed.