HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
jasonlion54

1973 Yamaha DT 250 magneto test

5 posts in this topic

I have a 1973 Yamaha DT 250 with no spark. I have a suspicion that the magneto has gone bad, but the wiring harness is a mess and the coil doesn't look so good either. I can't get a reading on my multimeter anywhere, so I figured I would start at the stator and then work my way to the plug.

Where should I put the test leads of my multimeter and what numbers should I expect? Also, should I be able to get any voltage anywhere if I kick the bike over while using the voltmeter? Thanks for any help you can give.

Share this post


Link to post
Share on other sites

I would check the point gap first. You should be able to put your meter on the green or red wire and to ground and get something out of it. Make sure the point gap is set first or you will not get anything out of the stator.

Share this post


Link to post
Share on other sites

Figured it out. The bike was wired wrong. Testing the leads coming straight out of the magneto with a DIGITAL multimeter while kicking the bike over by hand yielded no results at all from any of the wires. Turns out that a digital multimeter doesn't register fast enough to pick up those short, low power bursts. I went and bought an ANALOG multimeter and sure enough, one of the wires coming out of the magneto was making the needle on the multimeter jump a little bit, so I hooked that wire straight up to the coil and fired the bike up.

Thanks for your help guys, and hopefully what I learned can be useful to someone else.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0