Carb Issues

[skypilot]

Hey trikers, i know this is probably a common question, but here goes. I have an 85 honda 250es big red. Runs great except for carb problem? I had the stock carb rebuilt back to factory specs by local honda shop. I added a new UNI-filter air filter and a complete cobra exhaust, and now the engine seems to have intense heat. Burnt all the paint off the headpipe, and turned it white! If this is a carb issue, do i need to jet it, or can i adjust it somehow? Could it be outta time a little, or the valves need setting? I'm sorta mechanically inclined, just don't know what the problem is. Is the trike running rich or running lean? How can I tell? Trike seems to pop and backfire alot on deceleration.

[Macs]

You added more air flow so now it is running a bit lean it sounds. Do a plug chop and see what color your spark plug is. that will answer the question for sure. Also do a search for jetting 101 and it will explain everything step by step.

[pirate122]

I will say your cobra exhaust is the problem(back pressure) but if your pilot screw is not adjust correcly yes it can cause problem. just make sure your pilot screw is open between 1.5 and 2 turn not more,factory is at 2 turn and if it still overheat your cobra is your problem.

[cbx1170]

I have jetted many bikes trikes 4 wheelers etc. Dynojet kits Factory etc etc. If it were mine with new UNI a/c and Cobra pipe I would go up 1 size to 135 maybe 138 on main jet, up to 50 slow jet OR move needle clip to 3rd groove from top OR shim the needle up ~0.020 inch, mix screw 1/2 to 3/4 out from orig factory setting and run it hard!!.

[skypilot]

Whoa, the guru at the honda shop said carb couldn't be jetted? What is that all about? He says it was worn badly. I had the carb rebuilt to try to solve this issue in the first place. Air filter and cobra pipe were in place, so i don't know why they didn't do this . As for moving the needle clip to the third groove, does this work? Please explain step by step what i would need to do? Help!