HELP!!! ???

Ok here is the story. Last year in july i finally got the jetting to the point i was very pleased. 180mj 45pj YZ er needle 3rd clip. the bike ran great no matter what the weather was from then all the way thru November. About December the problems started and I have not been able to fix it. spent hours on it today.

The bike runs great on until the load gets really heavy. If i get in deep sand or gravel arroyos the bike starts cutting out, popping, backfiring, from about 1/4 to 3/4 throttle. I can baby it thru with very little throttle or i can run it wide open but nowhere in between. so i thought it had to be the needle. (WRONG) I went to clip #2 it was worse so i tried #4 clip it was better than 2 but worse than three. next i tried original needle clip #3 no go again. tried number 4, terrible.

Can anyone help me I am supposed to be going on a ride tomorrow, but at this point i will have to cancel




y2k wr, airbox lid and baffle removed, 180 main, 45 pilot, 426yz er needle,

wr timing

I feel your pain. Maybe this bike is a little to much for your, Shall we say, technical abilities? :) I feel that it would be a good idea if you seek out and purchase a 1982 XR200. Much easier to maintain and you might even get a little faster! :D I would consider selling the WR before someone gets hurt or seriously embarrassed. Maybe your next door neighbor would buy it. Of coarse you would have to sell it cheap because of its running condition. Good luck on your WR and I cant wait to ROOST your butt tomorrow :D No excuses!! :D see-ya



try blowing out the carb & cleaning the APJ system up (bowl etc).

i think that your MJ is too big & should have been a 175.

you can check your APJ by pulling the airboot out the way & getting someone to whack the throttle while you look in the back of the carb. it should last about 2 or 3 seconds.


ok guys it seem to be getting tougher. first i checked the exhaust, everything was tight, no problem there. then i pullthe car clear out of the bike. acc pump seem to work just fine. i pulled the rubber boot oh the back side took out the two jets there, cleaned them and the holes they goes in. took out the needle and slide took off float bowl main jet pilot jet fuel screw. sprayed everything down withacrb cleaner and put it all back together with the jetting i started with. on flat roads no ploblems. but get in deep sand or gravel in 3rd or high and can not use 1/4 to 1/2 throttle. as long as i kept it out of that range i was fine but ant mean a lot of hard acceleration which is not always fun when trail riding. if i tried to run 1/4 to 1/2 throttle it loaded up real bad and the only way to get it to stop was whack the throttle and hold on. again not the most fun on a trail ride.

has anybody ever had this problem? i dont have enough confidence in my dealership to take it there.

is there something i forgot to clean somewhere in the carb?

thanks for any help

dave in abq


y2k wr, airbox lid and baffle removed, 180 main, 45 pilot, 426yz er needle,

wr timing

Have you tryed draining the fuel?? or how about the intake manifold maybe cracked, or clamps arent sealing tight on the manifold, some times if they backfire real hard, they will blow the intake boot loose?? you did make sure the pilot wasnt plugged ?

Have you tried ?:

-a new spark plug

-check the spark plug cap & wire

-check the throttle position sensor resistance

Suggest you use a smaller main jet #170, but it's not going to stop the current problem.


how do i chech the tps? do i need a multimeter?

tried everything else other than the manifold being cracked or loose, will check that asap


There is a procedure in the manual using a ohm meter.

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