Adjusting idle

[yernkie]

On a stock carb (85 TRX250r) how do you adjust the idle? It is by turning the choke knob, right? Does the choke need to be up or down to do it? Which way would increase the idle speed? Do you have to loosen the nut below?

Stupid questions, I know. I have tried turning the know each direction and it doesn't make a bit of difference. Thoughts?

[265 sleeper]

When you turn the knob it will raise or lower the choke knob don't need any tools to adjust it .

[yernkie]

Mine doesn't seem to raise or lower the knob, which is why I thought maybe the nut needed to be loose. Any thoyght to why it wouldn't raise or lower?

[Meat]

Don't have to loosen any nuts. Keep the knob down, in the off-choke position. Warm up the bike really really good. Set your air-screw first, so its nice and crisp off idle. With the quad running, turn the choke knob in any direction and wick the throttle. Obviously if the idle goes lower, then turn the choke knob in the other direction. I forget which way raises the idle, but you'll figure it out quick. Don't be afraid to spin that choke knob a few times till you learn which directions to raise and lower the idle. But make sure your air-screw setting is in the right position first before you go fiddling with the idle. Ideally the air-screw should be 1-1/2 turns out from seated. And again, I gotta stress, you gotta set the idle after the engine is warmed up.

[yernkie]

I'll give it a try. Just seems odd because I went 2 or 3 full turns with no change.

[bloodswet&gears]

Have you cleaned the carb including all the passages? Take the choke out and see if it has a needle. May have a pwk choke in it.

[yernkie]

Originally posted by bloodswet&gears
Have you cleaned the carb including all the passages? Take the choke out and see if it has a needle. May have a pwk choke in it.

Yes, carb is clean. What would a pwk choke do? I am a total newbie to 250r's.

[leager-n-ky]

i had one do the same thing, cleaned it, turned it, and nothing. Ended up buying a new carb, some things just wear out.

[265 sleeper]

Just break down and buy a carb 200 bucks not bad for a new carb

[bloodswet&gears]

[QUOTE]Originally posted by yernkie
What would a pwk choke do?

A pwk choke has no needle. Just a seat. And it Just spins, has no adjustment.

A pj choke has a needle and seat. The needle screws up and down.

Take it out and post a pic. post one of the carb too. Sounds like something is missing or wrong or something clogged.

[yernkie]

Here is the choke. No needle. The carb is a Keihin. There are 2 screws on it. One near the top on the lower right and one near the bottom to the right of the bowl. I believe the bottom is the air/fuel mixture so it has been set 1.5 turns out from seated. I can play around with the top screw and get the bike to run, but only if I keep on giving it gas.

It was running fine yesterday, then I turned the choke thinking it would bring the idle down (because it was idling high) but then it died, It would only run after that by giving it by feathering the gas. I know now that turning the choke did nothing, so what could it be?

Edit: I drained the gas the night before because I didn't trust how the previous owner mixed it. Maybe in draining it from the tank some crap settled to the bottom and plugged the carb? But why would it run when giving it gas but not idle?

Edit # 2: I looked up the serial number. It is a PWK 38mm Air Striker.

[bloodswet&gears]

That is a choke from a pwk. If your carb is a 38 a/s then it should have 3 screws. One in the bowl to drain fuel. One air mixture screw. One idle speed screw that pushes up on the slide. An air striker will have fins on the side where the air first enters the carb. Inside at the bottom. Stock carb is a pj34.

So turn the screw in at the top of your carb and it should idle up.
Sometimes you have to cut half the spring off to get he screw in far enough. Or a short piece of vacuum hose that its real tight on the screw. You may have the wrong cable also. I like using a twist throttle with pwks. Seems to work better with pwks.

Pj's are more user friendly. You will need a smaller intake boot if you go back to a 34pj.

[bloodswet&gears]

Its running when you give it throttle because its running on something other than the idle circuit. Which sound like it may be clogged.

[yernkie]

Originally posted by bloodswet&gears
Its running when you give it throttle because its running on something other than the idle circuit. Which sound like it may be clogged.

I bet that is the issue. I'll pull the carb and check everything out. Thanks for the help.