I HAVE WROTE IN BRFORE ABOUT THIS PROBLEM AND RECIEVED ALOT OF GOOD RESPONCES. HOWEVER, THE PROBLEM STILL EXISTS. IT IS A 1986 LT250R ALL STOCK. TOP END IT RUNS WITHOUT A SKIP. DOES NOT LIKE TO IDLE VERY WELL AND LOADS UP TERRIBLE. IF I STAY ON IT AND KEEP THE REVS UP IT WILL KEEP A B7ES IN IT FOR ABOUT 3 TO 4 HOURS. B8ES IS OUT OF THE QUESTION. CHECKED REEDS, COMPRESSION, CYLINDER, TANK AND HOSES. MAIN JET IS 200. P[ILOT WAS 45 I CHANGED IT TO 40. NEW NEEDLE AND SEAT. NEW CHOKE PLUNGER. 1.5 TURNS OUT ON AIR SCREW. SLIDE NEEDLE IS IN MIDDLE, TRIED DIFFERENT NOTCHES WITH NO RESULTS. TOOK FACTORY SILENCER APART AND REPACKED AND SANDBLASTED. REWELDED BACK TOGETHER AND STILL NO CHANGE. GAS IS HIGH OCTANE FROM THE PUMP WITH 50/1 BELRAY MIXTURE. NEW UNIFILTER AIR FILTER. TONITE WILL BE THE CRANK SEAL AND THAT IS ALL I CAN POSSIBLY IMAGINE THAT IS LEFT. ANY IDEAS????? AM I MISSING SOMETHING STUPID???????? THANKS FOR HELP!!!!

 

umm, you didnt list any type of leaning the jets. If it wont idle, and loads up, its too rich. I dont know how to read a spark plug, but that is what you need to do. maybe someone can write in and say how to do it, cause i need to know too.

 

Come down acouple sizes in the pilot jet, this will lean it out at idle and not load up, also go back to about 40:1 mixture on the gas 50:1 is really unsafe it will blow up or melt the piston, especialy with that b7es go back to the 8's, If you have a clymer manual look in it it tell u how to jet ur bike in diff temps but start with the book, then go leaner from there
Hope this helps [img]i/expressions/face-icon-small-wink.gif[/img]

 

If your electrode is black, and your ground strap is a coffee with cream color, then you are a little fat, but that way if it drops 10 degrees, you dont have to rejet. A black sooty cabonated plug is rich, and a plugh that lookes sand blasted is lean.

 

I dont know the exact type of plug or a quadracer, but d*** thats a small plug, for a 2-stroke 250. If i were you I would try a BR8ES.

If the motors lean the plug will be a really light color, and if its rich it will be a dark color. If its perfect it will be a paper bad brown color. If it is loading up then it is probably to rich.

...If all else fails try a diffrent type of oil.

 

Dragracer, why is it better to use the resister version of the same plug?

Here is an awesome site for tuning a carb, http://justkdx.dirtrider.net/printcarbtuning.html.

 

Isn't that br7 a colder plug than an 8? I run the 8's in my LT250. And the 50/1 ratio mix makes your mix richer overall, I'd go to 32 or 40, and use the br8 plug, and try that first. Looks like you covered a lot of the other bases. Good luck!

 

here some hints.
when rejetting or sliding the needle make sure to blast down the road to clear things out and then check the plug.
i got mine jetted and got the plug to a nice tan color which is what you want. but after washing mine it wouldn't start and when it finally did i fouled the plug again...i am going to look into my electrical now to see whats up with that GRRRR it never ends

but my point is take a peak at your electrical also. you should be getting a nice spark down there. i also thought my seal on my crank might be gone. but it wasnt that
i also was going to junk my carb but after dropping the needle one notch and going to a 30.5pilot 210 main with the lid on belray at 50:1 it helped with the problem and i got a nice tan color. but i am still going to check into the electrical because i seem to lean on the pilot to get it to run right. my next guess on mine is maybe the coil isnt producing enough electricity? hoping to check it with an OHM meter this weekened. and i still have these headaches after a total motor rebuild [img]i/expressions/face-icon-small-tongue.gif[/img]

another problem i am having is when i go to start the bike when its cold it takes 10 to 15 kicks,then when warm 1 kick. but when cold if i change the plug usually fires right up. hehe

 

my blaster use to do the same thing,i got a 30mm carb with a setting installed so you did not have to jet ur carb,u just turned this adjustment on it,and it allso elimiated the T.O.R.S. (throttle, overide, switch) that is the thing with the idle,but the 30mm carb had a idle screw on the carb,i got this carb from vitos performance racing,SO IT IS EITHER THE T.OR.S.,SPARK PLUG,OR IGNITION TIMING,MAGNETIO KEY. maybe get a dyna ignition.

 

Take the side cover off and look at your pickup coil. Sometimes those get wet, and the water cannot escape from inside there. Happened to me before.