1974 Dt125 Spark

[big_dave]

I bought a old 125 enduro, and it has a Generator in it. The points looked rusty so I am getting new ones. There was no spark. Has anyone else worked on these generator model 125's? Any tricks or tips you could give me? I am looking for some good gas mileage for a around town ride.

Thanks... Big_Dave

[LoserShoes]

If the points don't help, try disconnecting the wire to the ignition switch. It connects the + side of the coil to ground to kill the engine in the off position. If the switch is bad, no spark. Super simple ignition system, with good points the plug should fire when the engine is kicked through.

Steve

[big_dave]

125 spark

Thanks Steve, I will try that.

Dave

[birch]

no spark

Hey, I had the same problem. I took the stater assembly completely out and sanded down the magnets on the inside of the left cover. Still nothing. I then found a small fuse under the seat. That was busted so I replaced it and thought that surely would be the fix. Still nothing. I then put some jumper cables on the bike and Walla!

Try jumping the battery. It will work.

Does anyone here know how to bypass the battery and get juice to the coil/points without the battery?

Casey b.

[big_dave]

DT125 no spark

I haven't gotten the new points in yet or checked to see if the Ignition switch is good or bad. I do have a BRAND NEW battery in the bike. Why Yamaha ever put a starter on a 125 I will never know. Just another thing to fail. I wished I had a magneto, and not the generator. I will try all the ideas I have gathered here.

Thanks... Dave

[LoserShoes]

If you have points, you have a magneto, the latter ones with CDI didn't have points, they had a pulse pickup. These needed the battery to run.

By the way, you do know that you need a puller to get the magnet wheel off?

I can give you the part number, but the Yamaha puller is pretty universal.

Steve

[big_dave]

dt125 no spark

My bike has a generator acorrding to the manual. I know it is NOT a CDI unit. I have pullers available if I need one.

Thanks... Dave

[birch]

Generator or mag?

When I was a kid, I had an dt80 and my father bypassed the battery. I ran that thing forever. Does anyone know how to bypass the battery and just run off the mag/gen. I was thinking it through the other night and thought that I might bypass the battery by running the hot wire directly to the coil. Will that work?

Thanks
Casey b.