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1974 Yamaha Enduro points...

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I just got my hands on a Yamaha Enduro DT250B from 74 (Orange Tank), the guy who gave me the bike also gave me a '75 Official Yamaha DT250B Shop Manual. I got this thing running like new (HAS 2630MI ON ODOMETER!) and it screams..man does it scream.

As soon as I got it running, I took it out for a spin, unfortunately it was misting out, light, light rain. Normal here in massachusetts. I ran it like a normal trail biker around the neighborhood, just to see how it ran, drove it for an hour. Spark dies.. I've gotten the coil and coil wire tested. Trying to diagnose the magneto, I have 2.0 megapixel pictures of the magneto. The right coil has a couple of light light blueish burns (the bigger of the 2 which im sure is the lightning coil). I've used a multimeter on the 1kOhm setting and tested it for continuity, it reads infinity. Not really sure if it's actually holding a charge though.

I'm looking for advice on rebuilding the magneto. I've already refurbished the coil contacts and magnet contacts, a little sandpaper and touch up wit the steel brush on the dremel. I'd like to get this running, it's alot more frustrating now that i've spent 1 week, getting the fual and air tuned, and spark shits out, but it was expected. At 30 years old. Pretty much after this all thats left to be done is a complete rebuild, rewiring and paint. Everything is in operational condition.

Everyone HELP! This is my first bike!

I'm waiting to try and get a hold of my friend to test for capacitance on that condenser.. can't really figure out what else to do?. Points were good after a little sandpaper.

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I Had a stator problem on a 85 YZ 250, the bike would run fine for 15 to 20 minutes then die out. The problem was traced to porosicity in the stator coating, as the coating heated up it would expand enough to create a ground...

The problem was a [@#$%&*!] to troubleshoot because it tested fine except when very hot.

You could have a simular problem, something to consider if everything else is good.

I would also give it a full tune up replacing plug, points and condenser.

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