250r coil testing

[wanta86r]

i suspected my coil was bad on my 86 R. It had a misfire at high rpms so i tested it tonite. There was no primary coil resistance, and the secondary coil resistance checked out with my manuals specs. So knowing now that the primary resistance is not in spec, what would you guys think this would effect. Am I in the right direction or way off? i wanna know if the coil is the problem.

[wanta86r]

nobody knows anything about coils huh- strange

[wanta86r]

come on guys, i need your help!

[wanta86r]

Anyone With Any Info?

[slothminx]

i wouldnt say it was your coil if its only missing at high rpm sounds maybe more like a carburation problem but for testing the coil if you want, get your multimeter and test from the positive terminal to the negative the resistance should be around 20-30 ohms. If thats ok test from the negative terminal to the spark plug cap this should be around7,000-9,000 ohms. If your resistances are a small amount out you shud be ok, but if there way out i would suggest borrowing another coil just to test if you get the same problem

will

[wanta86r]

Ive already tested the coil. it doesnt read any resistancebetween the two terminals- didnt you read the post?

[slothminx]

sorry:( i didnt read it properly i though you wanted to know how to test it. i think its unliky to be your coil as they start showing that there bad when they get hot not at high rpms. i would try giving the carb a clean if you havent already done it, make sure your main jet is clear.

[wanta86r]

so your saying that even though the coil has no primary resistance, that it is still good. im not sure i agree with that. and the carb is brand new along with the top end, reed valve and pretty much everything else

[slothminx]

if it had no primary resistance the whole thing would not work at all. have you tried a new plug? 2strokes do miss at high revs if the plug is slighly fouled. if you dont think im right please just ignore me, but im only suggesting things it could possibly be

will

[TimSr]

First, it helps if you dont bump your post to the top every couple of hours. It makes you look obnoxious, and your thread will get removed by the moderators. Do you want intelligent answers or do want all the post whores to enter in their two cents worth whether they know anything or not?

If you have spark, your coil is working. The most common failure of a coil is insulation breakdown or cracking, which will not show up on any meter. The easiest way to check is to start the bike, warm it up, and then spray some water directly on the coil. If it spits and sputters, youve got insulation problems. 90% of the time, replacing the plug boot (about $3) will correct it. The other 10% of the time it may be a damged wire or coil insulation, in which case the coil needs replaced. (There are a few models that allow you to change the plug wire, but more do not) On some models, sputtering may occur from a bad ground, as the use the frame mounts as the ground.

[slothminx]

I hope your not refering to me as a post whore :cry: as i am certainly not i was only try to suggest some things that could be tried.

will

[wanta86r]

i have spark, and it ran except for the high rpm misfire. i tested all electrical mth a multimeter. the secondary resistance checks out with my manuals specs, however there appears to be no primary resistance. i thought maybe i just didnt know how to use the meter, but every other test i did(as shown in manual) checked out .

[TimSr]

I hope your not refering to me as a post whore :cry: as i am certainly not i was only try to suggest some things that could be tried.

will

I was NOT referring to you. I was referring to few people who see fit to respond to very post whether they have a clue or not. You do not fall into that category at all.

[wanta86r]

what do you think tim?