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Alright, I finally got enough good responses you fellow kzrider members to buy a yamaha rd350 i addressed in a previous post. After further inspection I was surprised to see that the bike only has about 8,000 miles.(not a real surprise i guess, it is a 2-stroke) It SUPPOSEDLY ran about 3 years ago when the owner believes the coil burned out. He said he tested the connection with a multimeter and determined it was bad. Once I got it home i did a further inspection. I pulled each plug and tested them for spark. What i discovered is that both coils were NOT giving power to the plug.(dont know if that is worded correctly). This would mean that both coils were bad or that there is a problem elsewhere in the wiring harness. Is it very possible that both coils would go bad at the same time? The wiring harness seems fairly simple on this little old bike. Where else would you suggest looking to solve this problem?

No spark with either coil? That doesn't mean the coils are bad. There is LITTLE chance that both coils will fry/fail at the same time... more likely the ignition is bad. Since neither coil is firing, it is more likely the ignition module than the pickups at the crankshaft... Not saying that both coils might not be bad but when things fail, a single point failure is more likely than two things failing. Coils fail for two reasons... old and get cracked and short from the outside and old and heat will destroy the insulation inside the coil and they short. A good way to test these coils is to take a multimeter and put on the meter (ignition key OFF) on the hot wire lead or lug and the wire from the ignition lead or lug. With the meter set in Ohms scale in the smallest scale like 1X or 10X, check the primary resistance of the coil. Not sure what it will be for this bike but if both are the same and in the 2-4 Ohm range, I would expect the coils are OK... you can also check the secondary windings in the coil by putting the meter (still in Ohms) into a range where you can read 10K to 20K Ohms and again, if both are the same and within that range, I would expect the coils are OK... oh yeah, you put the leads onto the metal where the spark plugs connect. If you can remove the plug wires, that is best but if not, put them on the leads where the plugs clip into the caps. If you find the coils are both shorted, that is both show infinite on the meter, then I am wrong and the coils are bad but if my guess is right, I would look for a new ignition module and get a service manual as there are test procedures there for both the ignition module and pickup coils.