XR250L carb question

Hello to all.

I am new to this part of ThumperTalk as

I have just purchased a 1993 XR250L, completely stock.

to start commuting with before my truck drains my wallet.

When I got it home, it would not want to run unless I have the choke on full.

Turn the choke off and it dies. I took the Carb off (almost harder than my CRF250X :naughty: ) and took it apart and cleaned her out.

Smell of old gas was apparent, so I new it was sitting for a while.

I got her all back together, put fresh gas in and she fired right up.

I took her for a spin and after she was warmed up I got her to a nice idle.

My problem is that she takes a long time to come down to set idle and

keeps her RPMs up between shifts. Very slow decelaration.

When I put the carb back together, I set the air screw to 2 turns out.

For some reason Honda made it so you can't reset the air screw without turning the carb (good luck) or take it out.

It only allows you to turn it one way or the other about a half turn.

The hand book does not say where the starting point for the air screw is....

(1 turn out? 1-1/2 turns out?)

Anyone have some insight as to what my trouble may?

With all the air pump hoses and BS they cram in there, I don't know

where to start.........

:naughty: Thanks in advance.


cut the tab off with a pr of cutters, it will allow you to adjust it without removing the bowl every time . All that tab is is a stopper which was crimped over the brass screw.

2.5t out should do it, anything past 3 t out will require rejetting

the reason that its not returning to idle between shifts is likely the throttle cables are gummed up internally,lube them or better still change them.

Loosen the tank to see if by chance the cable routing inhibits the proper usage of the cables

All that paraphenalia around the carb is all anti pollution stuff .

You have an accelerator pump on that carb, properly tuned it works great.


Thanks Stu,

I did check the cables and they are fine.

It really feels like an internal carb thing.

I am not sure about the accel. pump and if it has one.

I need to get a mechanics manual for it I guess.

It might be a slow jet issue, or I need to tweek the air screw a bit more.

I will be looking into a carb rebuild kit too.

Cracks in orings and gaskets might do weird things.

Thanks again.


As Stu says, the carb has an accelerator pump.

Check this out:

XR250L Project

:naughty::naughty::D RAMZ :D:D:cry:

yeah, check the intake boot close too, any place that might suck air, that will generaly make the revs hang abit

I will be looking into a carb rebuild kit too.

it comes with the mini O rings and the works , it might be a good idea, some of the parts are impossible to find on the carb itself.

Check sudco, they have several exploded views of carbs, you might find the right one , the Honda shop manual is an excellent idea


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