-
Welcome! You are currently logged out of the forum. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please LOG IN!If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the benefits of membership? If you click here, you have the opportunity to take us for a test ride at our expense. Enter the code 'FORUM25' in the activation code box to try the first year of the MOA on us!
Heated grip resistor
- Thread starter bmwrebel
- Start date
MotorradMike
Lucky
I'm guessing the resistor you want is switched in to reduce current through the heaters.
Measure the heaters and match that resistance in the one you buy to divide the power evenly between the resistor and the grip heaters. You'll need a power resistor, probably 20-25 Watts. It's going to get hot.
If this was my bike I'd use a PWM controller like a heattroller to infinitely vary the heat with about 1% loss. Doesn't get hot.
If you are handy with a soldering iron you can build one. If you need a schematic let me know.
Measure the heaters and match that resistance in the one you buy to divide the power evenly between the resistor and the grip heaters. You'll need a power resistor, probably 20-25 Watts. It's going to get hot.
If this was my bike I'd use a PWM controller like a heattroller to infinitely vary the heat with about 1% loss. Doesn't get hot.
If you are handy with a soldering iron you can build one. If you need a schematic let me know.
cjack
K Bikes Complex by Choice
I have aftermarket heated hand grips on my K75S and the resistor for the low heat burned out. There is no marking on it to tell the size.Does any one know what size to ask for at Radio Shack? Thank you
The stock grips were 8 ohms each, in parallel which makes 4. Then the dropping resistance wire harness (it's a neat way to do it, even for aftermarket heated grips) is 2 ohms. Be sure to fuse the circuit at no more than 4 amps in case a grip shorts because the 2 ohms would be across the whole power supply in that case (ie, too much).
So at 13 volts, the power in the grips (two of them) is 42.25 watts. That's 21.12 watts each. With the 2 ohm dropping resistor in series, the power is 9.39 watts each. That comes out about right for the heat HI/LO. The 2 ohm resistor then when on LO heat is also dissipating just under 10 watts. That needs to be on a heatsink or use BMW's resistance wire harness.
