Please can someone help me

[Slater]

Hi guys, new here. I have a 1986 250 Big Red. I am having problems with it running rich. I put a new carb on, valve clearance is good timing chain is tight, new plug, new coil, gas cap is fine any thing I do makes no difference. I can get it started and it runs rough then the plug fouls up. I don't know what else to do I hope someone can help me. I was thinking of just selling it and be done with it but I have owned it since new and I really love the thing.

[shortline10]

New aftermarket carburetor is probably not jetted right , most are junk , if you have the original carburetor rebuild it or get it rebuilt by a professional.

[Slater]

I rebuilt the original but it didn't make any difference so I bought. New one but that didn't change anything either. Thanks for your help though.

[shortline10]

Other things you can check are compression / leaky valves or worn piston and rings .
Weak spark can also cause your systems , bad CDI or stator and grounds .

[Slater]

Compression is good, if it was cdi it probably wouldn't start, I am getting a nice blue spark but I will check the stator. Thanks for the help.

[Slater]

Anybody know the range for a static test on a 250 es stator?

[big specht]

Or a bad coil I’ve had bad a bad coil before even tho it had good spark or junk spark plug I’ve had had junk new plugs too

[Scootertrash]

New aftermarket carburetor is probably not jetted right , most are junk , if you have the original carburetor rebuild it or get it rebuilt by a professional.

This would be my first suggestion as well.

How many carbs have you rebuilt in the past?

How far apart did you take the carb to do your "rebuild"?

Did you use one of those welding tip cleaners to clean the jets?

Did you use all new gaskets and seals? OEM parts?

Float level correct?

If it were me, and I've rebuilt quite a few carbs, I go back to the old carb, disassemble it and make sure everything is where it's supposed to be and your initial adjustments are correct, then install it and go thru the jetting procedure.

Do you have a manual?

Here is a link to the jetting procedure at the top of this page:

https://www.3wheelerworld.com/showthread.php/55086-Carb-Jetting-101-Terms-Tips-and-Jetting-Theory

Sometimes it's better just to go back to the very beginning and start from scratch.

[Slater]

I put a new plug in and a new coil. I rebuilt the old carb but it didn't do anything so I bought a new one. Everything.I do seems to make no difference. I took the cable off the fuel enhancement so it would go down to its seat. I'm no mechanic but I I think I tried everything. I sure appreciate all the help but I think I will sell it the way it is. Kinda out of options.

[Shep1970]

Throw away any parts u bought from china. Start there.

shep

[YTZ drew]

Bring home some fresh fuel in a known clean can, and try running it on that, fed from a remote tank. Could be bad fuel or contamination in your tank. I can't even count anymore how many times I've helped people with running problems and it has turned out to be bad fuel.

[Slater]

Tank was taken off and totally cleaned. I only use Shell 91, has no ethanol. I always remove my gas every winter.

[newc14]

So I know a couple people along this thread have asked similar questions, but I think some specifics might be getting left out. I'd hate for you to sell your trike when it could be something simple. I've dealt with over-rich issues and by and large it is often carburetor related. I know you said you rebuilt it already, could you go into detail what went into that? Did you buy a kit and where from? What parts did you replace vs clean and reuse? Do you know what # jets you used?

The aftermarket carbs are hit and miss. I've had some work great and some you could fight with forever and never get it right. The best option is to go back to the carb that *was* working and start there.

None of this is meant to belittle your efforts or anything, but getting a carb to work right is half mechanical know how and half magic, and I want to make sure you have the right ingredients before you throw in the towel.

Edit: Stupid question, but just to check. Have you messed with your idle screw at all?