XR woes

[nudemetalz]

Greetings,

I lent my '91 XR250 out to a friend so he could go riding with his father around Red Rocks. It's in not bad nick.

He said it got him right around as far as you could go (about Cave Bay) no worries. Then it started cutting out. It would die completely and then it would start up okay, go for a wee way and die again. He managed to get it back to the carpark but was a little concerned obviously.

This is the first time it's done this. The engine is normally very sound and goes like it should.
I'm going to strip and clean out the carb. It's got a new plug in it.
You think I should do the plug lead & coil also?

I know this should be in the "Engine Repairs" section but figured there would be more knowledgable XR riders here that have had it happen to them.

Any help is appreciated.

Cheers,
NDMz

[B0000M]

a mate of mine had a similar problem, would go ok for a bit, then start dieing, turned out to be the stator windings, not cheap parts either. im not sure how you test them tho

[merv]

Could be crap in the carb or did he get any salt water on the electrics such as plug cap - maybe its slightly cracked or something, similarly with other ignition parts? Try changing them as you suggest but if water caused it they'll be OK dry but probably do it again if they get wet again, so yeah if you troubleshoot the right thing, replace it.

Another classic is chaffed wires on the kill switch circuit just have to touch the frame somewhere and kill the bike. I had a bad case of that competing in an enduro way back on an XR in the Lismore forest out of Wanganui. Every time I turned the handlebars slightly right the engine died, turn left quickly it fired up again. Traced the chaffed wire and taped it up and rerouted it a bit. That was fun on steep slippery slopes I tell you - far worse than the gravel around the coast.

[nudemetalz]

Thanks Merv and B000M.
Shall check those.

PS when I get it running we must go for that ride like I suggested a while back, Merv.

[Paul in NZ]

Also check the tank vent is not blocked. Run it till it dies and whip out the plug - see if it's wet or dry??

[nudemetalz]

I did figure that, but the tank vent is fine (blew through it etc).

[Lurcher]

This is an outside possibility but......

Inside the sparkplug lead on an XR250 there is a screw, underneath this screw is a spring followed by a resistor. A lot of people toss the resistor and replace it with a small piece of either stanless steel or copper rod of the same dimensions. This helps with starting, and some people report an improved throttle response but this is varible but if the resistor has died replacing it might help.

[nudemetalz]

This is an outside possibility but......

Inside the sparkplug lead on an XR250 there is a screw, underneath this screw is a spring followed by a resistor. A lot of people toss the resistor and replace it with a small piece of either stanless steel or copper rod of the same dimensions. This helps with starting, and some people report an improved throttle response but this is varible but if the resistor has died replacing it might help.

Thanks for your response.
I have heard that also. I am going to replace the lead anyway.

Cheers

[sAsLEX]

a mate of mine had a similar problem, would go ok for a bit, then start dieing, turned out to be the stator windings, not cheap parts either. im not sure how you test them tho

About 10 dollars for the wire, and about four days labour counting the turns off , then back on again using the wrong wire the first time and having to do it again.......

[mc4aregreat]

Don't forget it could just be simply a faulty kill switch.

[nudemetalz]

Don't forget it could just be simply a faulty kill switch.

Thanks, that is worth a shot.
I'm going to go right through all of the wiring on it (not a hard job as not much of it )

[F5 Dave]

I'd drain the carb into a container & look for water rolling around. if so some meths in teh tank, or drain the whole tank. Surprising how some water can kill a single dead.

Maybe its an XR thing. Mine did it the day I went to sell it. Maybe it noticed a new bum on seat.