Need help with electrics

Onecos · Post by **Onecos** » 18 Oct 2009 17:40

Several months ago I turned the key and smoke came from under the tank/seat of my 1981 250 2C. One of the transducers looked slightly melted. I purchased a pair of used transducers and a used pickup. I've done all the tests in the blue book. Have power from the magneto, can see juice into the transducer etc. However, no spark. I have a mechanic friend helping me but he's now in jail (5th DUI). What should I test next? I can't have 4 bad transducers... could I?

I purchased a pair of black OEM 3 1/2 silencers. Thought they would fit the 2C but the ID is 35mm and the 2C is 32mm. I'll figure out what I paid and will sell for the same. I think is was about $300 US. Probably a deal as the dollar is currently tanking. Hey, I still have a job....

mgill · Post by **mgill** » 18 Oct 2009 20:13

The 3Â½ pipes are 32mm.

hendre · Post by **hendre** » 19 Oct 2009 06:11

500 mufflers are 35mm

hendre · Post by **hendre** » 19 Oct 2009 06:13

as for electrics, there are a few stories of smoking Morini bikes when you reversed the battery terminals. Then ussually the power regulator is also busted but that does not interfere with your spark.

Do you have the correct transductors? Is there a part number anywhere?

EVguru · Post by **EVguru** » 19 Oct 2009 09:10

The green wire running from the transducers to the ignition switch is gounded to stop the bike. If you apply battery voltage to the transducers they will burn out and a faulty ignition switch can do this. The 250 2C should have a diode in circuit to prevent a faulty ignition switch from burning out a transducer (as do the lather 350's).

I would carefully check over the wiring to make sure it's stock. The diode is factory fitted with a bit of terminal block and looks like an 'owner mod'.