WaldoVH

Member
Nov 2, 2006
27
0
I'm stumped!

After being out of the dirtbike thing for 15 years I bought a 93 RM250 about a month ago. I got about ten minutes of ride time on it then bam no spark.

I replaced the Coil with a used one I bought on E-bay.

I put on a new stator coil, a new pulser coil. a new CDI box. I've checked all the wiring for shorts and for breaks, I'm pretty much stumped.

When kick the kickstarter with a multimeter on the wire from the CDI box (not the CDI wires that goes to ground) to the coil brings the voltage up to about 15 volts then slowly drains back down. If I keep kicking constantly it seems to go up and down between about 16 and 12 volts then slowly drains to 0 when I stop. I'm not sure if the voltage would stay the same or move if I was able to keep the engine rotating at a constant speed.

I have tried to measure voltage from the pulser coil but am unable get any voltage reading from either my old one or my new one on the bike. I can get the multimeter needle to move if I pass a stronger magnet past the pulser coil. The magnet on the rotor will stick to my screwdriver but isn't hugly powerful. I think it's OK because the magnet is about as strong as the one that is bolted to my Kart axle to measuer speed. I also don't think there is much a guy could do to break a rotor or wear out the magnet.

The only two things I think it could be are the rotor or possibly I bought a bad coil on ****. What do you guys think. (besides get rid of the POS and buy a new KTM 300 EXC)
 

jj canuck

Member
Oct 28, 2006
13
0
did you try changing your plug? if you buy a manual for the bike they should have all the risistance values in it. where did you get your cdi from? i had a hard time finding one at a good price!!
 

WaldoVH

Member
Nov 2, 2006
27
0
Changing the plug was the first thing I did, before I started spending real money.

I got my CDI box from ****. I don't think the old one was bad but this guy has a new old stock one for a buy it now price of $69 so I snapped it up.

Darn jj I noticed in another post that you had just been through electrical problems on a 94 and was hoping you'd have the magic bullet for me!

I'm waiting for my manual in the mail.
 

WaldoVH

Member
Nov 2, 2006
27
0
I've disconnected the kill switch. It just unplugs from the harness. It's not shorting anywhere and it works. I've tested it with a multimeter.

I don't think the spark plug was toast but I tried a new one just in case. Yes, I've had the plug out and grounded it to the head and kicked it over. I've even held it in my hand, You have no idea how happy I would be to get shocked.
 
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