So I have a green bike I've had for 2 or 3 months now and it runs a 19mm Dellorto PHBG carb with a manifold to match attached by a short 1" I.D. hose. There's no air filter on the carb either. It's also been raining here on and off for over a month (not a single day yet without rain)
So I've burned out 4 magneto coils so far. The first 2 times it wouldnt start, removing the cover, lots of water poured out. I figured I shorted it out. So after that, I sealed the crap out of it using a liquid rubber leak sealant, assuming a leaky gasket. Next big rain, riding around, bike died again, a good distance from home. Stopped at a store and asked for a screwdriver. The instant I removed the bottom-most screw on the magneto cover, water poured out. it poured and poured and poured some more, the amount looked to be enough to fill the cover halfway with water.
So I dragged it over to the shop (my gf was riding it, and I was riding mine) and I've since determined water is burning it out, and getting in through the uncovered carb. So I drilled a tiny drainage hole (something like 5/32") so water wouldnt collect, and replaced the magneto and rode it home. Then at home we covered it with a tarp and no longer ride it in the rain or wet areas.
Next clear day I had made some other repairs and modifications and went to test them, and the bike wouldnt fire. It fired intermittently as it did when the other 3 magnetos burned out. But this time... there's no water in the cover, the drainage hole would have drained it enough that it wouldn't touch the coil, and the bike was covered during the rains.
So I'm at a loss here, anything I should check?
EDIT: The thin steel plate under the magnet that separates the magnet from the oil seal is bent, probably from water forcing its way through. I smacked it back down with a screwdriver but it keeps popping up. I'll replace it but I doubt that would cause the issues, but I could be wrong? Green bike runs a stock CDI with a jaguar coil plug boot (the vibrations at high speeds would shake the stock boot off the plug.
Comparative note: The black bike I've been riding for almost 2 years now has been out in the rain, both uncovered, and even riding. Has no air filter either, and never burned out a coil. It runs a jaguar CDI.
So I've burned out 4 magneto coils so far. The first 2 times it wouldnt start, removing the cover, lots of water poured out. I figured I shorted it out. So after that, I sealed the crap out of it using a liquid rubber leak sealant, assuming a leaky gasket. Next big rain, riding around, bike died again, a good distance from home. Stopped at a store and asked for a screwdriver. The instant I removed the bottom-most screw on the magneto cover, water poured out. it poured and poured and poured some more, the amount looked to be enough to fill the cover halfway with water.
So I dragged it over to the shop (my gf was riding it, and I was riding mine) and I've since determined water is burning it out, and getting in through the uncovered carb. So I drilled a tiny drainage hole (something like 5/32") so water wouldnt collect, and replaced the magneto and rode it home. Then at home we covered it with a tarp and no longer ride it in the rain or wet areas.
Next clear day I had made some other repairs and modifications and went to test them, and the bike wouldnt fire. It fired intermittently as it did when the other 3 magnetos burned out. But this time... there's no water in the cover, the drainage hole would have drained it enough that it wouldn't touch the coil, and the bike was covered during the rains.
So I'm at a loss here, anything I should check?
EDIT: The thin steel plate under the magnet that separates the magnet from the oil seal is bent, probably from water forcing its way through. I smacked it back down with a screwdriver but it keeps popping up. I'll replace it but I doubt that would cause the issues, but I could be wrong? Green bike runs a stock CDI with a jaguar coil plug boot (the vibrations at high speeds would shake the stock boot off the plug.
Comparative note: The black bike I've been riding for almost 2 years now has been out in the rain, both uncovered, and even riding. Has no air filter either, and never burned out a coil. It runs a jaguar CDI.
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