Quad stalls if throttle applied to fast..........

[Rider-trx_250ex]

I have a uni air filter, outerwears airbox cover, removed snorkal and replaced with pantyhose, a slip on pipe, and put in a 110 main jet.......(i went by the 250ex performance faq thread) and the quad idles fines but if I try to give it gas fast the quad stalls...............I have to apply throttle very gently or else it will just stop. I tried cleaning out the fuel filter and it was alittle dirty but thats wasn't the problem.

The carb had some thin oil like substance on it but i cleaned that out too.

It seems that a bit of oil is coming out of the engine thorugh the pulse generator cable plug(the cable right next to the crankcase breather tube)

I cant ride the quad until i put on the brakes and tires but I checked the new spark plug I put in and it was a little black. What gives?

[gojk]

Possiblity of two problems. Could be your accelerator pump not working right, although I doubt that would make it die, you just wouldn't have the throttle response.

When this was happening on my 400ex the needle was a little rich.I would try moving the needle up one notch. That should lean it out a touch. If that makes it better but doesn't fix it, try one more notch.

[Rider-trx_250ex]

Originally posted by gojk
Possiblity of two problems. Could be your accelerator pump not working right, although I doubt that would make it die, you just wouldn't have the throttle response.

When this was happening on my 400ex the needle was a little rich.I would try moving the needle up one notch. That should lean it out a touch. If that makes it better but doesn't fix it, try one more notch.

I dont think 250s have an accelerator pump, only 300s and up and i tried moving the notch up one then up another but didn't work.............

[gojk]

Originally posted by Rider-trx_250ex
I dont think 250s have an accelerator pump, only 300s and up and i tried moving the notch up one then up another but didn't work.............

Does it stumble if you roll on the throttle?

[Rider-trx_250ex]

Originally posted by gojk
Does it stumble if you roll on the throttle?

Could you define roll on the throttle please.............like go from closed then to WOT?

it can do that being too rich or too lean, i've had it happen both ways. You have to see which it is and play around with it. Do a plug check on the main, run it WOT down the road or something and hit the killswitch, dont let off before hitting it. Dont start it back p or anything take the plug out and see what color it is. Now you know your main. Now mess with that and then play around with the needle to get it just right where it doesnt cut out or want to shut off when you hit the gas. I've been having the same problem with stabbing the gas and it cuts out and shuts off.

[gojk]

Go from no throttle to WOT without stabbing it hard.

Does it stall even if it is not moving? Or only while the engine is under load.

[Rider-trx_250ex]

Originally posted by gojk
Go from no throttle to WOT without stabbing it hard.

Does it stall even if it is not moving? Or only while the engine is under load.

Well the thing is I've got a concussion and I'm in the process of recovering so I try to work on the quad little by little when I'm feeling good but I don't accopmplish much at one time but I have to mount the tires still, and put on the front and rear brakes. So I can only rev the engine since there are no brakes or tires on.

But it does not stall when I roll on the throttle.

[pro-rider46]

wait until you can ride it, my crf does the same thing without load on the engine

[Drewltr450]

its your jetting

[05Z400rdr]

This may sound stupid, but is your fuel turned ALL the way on for sure? Yesterday I was helpin him on his quad and it was doing the same thing, then I looked and here the fuel was o nly turned partially on, so it wasn't getting enough fuel when it needed it.


Landon

[sc400ex_rider]

does it do it under load? mine does the same thing but in gear its fine. jetting is off a little but not very much.

reving the pi$s out of it in nuetral only impresses noobs. :rolleyes:

[Rider-trx_250ex]

Originally posted by sc400ex_rider
does it do it under load? mine does the same thing but in gear its fine. jetting is off a little but not very much.

reving the pi$s out of it in nuetral only impresses noobs. :rolleyes:

Idk if it does it under load.....i gotta put front and rear brakes and bleed the front brakes before i ride it.....wth are you talking about about reving the piss out of it?

[04TRX400EX]

I would think that it is running lean because rich would not make it die, it would just bog or "stumble" a bit. If it is running lean, the carb is actually starving for fuel and is eventually being overrun by air causing it to die. Since it is occuring while you are on the gas, I would say it is your main jet since that controls all fuel delivery from 1/4 to WOT. Do the plug check as noted above when you can get it back down on the ground and ride it.