ballast resistor

[xsscooters]

I have a question the ballast resistor covor fell off and it looks like the resitor is bad. If the resitor is bad will this make the bike run bad ? It was running great now it has no power and cuts out real bad from idle on .

[Snow]

I can't remember for sure, but I believe the ballast is bypassed for startup and in use during normal riding. The only problem I could see is that it would either not run or it might end up frying the coils if they are stock. Someone please chime in

[planedick]

I think.....

I believe that the ballast resistor cuts the power to 6 volts or so after the starter is released. It puts 12 volts to the coils to start, but after the starter butten is released the volts go to 6 volts. I think running it for any extended period of time will cause overheating of the coils and burn them up.

[randy]

xsscooters;

Snow is right, you need the ballast resistor for normal running. Appears that it was frying (for some reason) and is now intermittent? Be careful with your fingers, they run pretty hot even normally. Try swapping with a good one. Need one? You can PM me but I won't be able to ship it 'till 2/12.

[xsscooters]

coils ?

Could the coils cause this part to fry . Its definately not getting enough spark all 4 plugs are wet and the pods have gas in them too. I just rode it a short distance before i noticed the top of ballast on the head of the motor.

[TopCatGr58]

Hey Scooters,

The older model bikes use the 1.5 ohm coils, and the 1.5ohm resistor. The TCI routes full 12 volts to the coils during startup, but then routes the power thru the resistor which drops it down to 9 volts to reduce heat. The coils probably did not damage the resistor, but it is probably the other way around.

The resistors either crack and fail breaking the power circuit to the coils, and so the bike WILL FIRE WHEN HOLDING THE STARTER BUTTON, but once it catches and you release the button, it dies, cause when the power gets routed THRU the resistor, and it's broken, no power gets to the coils!

The other way is that it can short itself, so that there is NO RESISTANCE, just straight 12 volts thru to the coils overheating them and burning them up!

You can get fairly inexpensive 3 ohm dual high output coils from MikesXS, and then just bypass the resistor, just connecting the wire ends that go to it together!

The later model bikes, 81 and XJ use the higher ohm coils and don't use the ballast resistor. You can check the ohmage values for your coils to see if they have gotten burned. And then check the voltage on both sides of the resistor to see if it is still working.
T.C.

[xsscooters]

Mikes xs

Is the part no on Mikes Xs 17-6803?

[TopCatGr58]

Yes it is, here's a thread I posted a while back about this, need to make it a tech tip! Good info IMHO! I have since ordered a pair, haven't put them on yet, but plan to along with my custom GREEN spark plug wires I found!
T.C.