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Supermoto XR600r

AC volts coming from the brake light

14 posts in this topic

AC volts coming from the brake light

Anybody got any idea why I'm getting a AC power going to the back light and not DC

I replaced the Slater and ever since I'm getting a AC power to the back light, the front light are working but not the back

Plus the green and white with yellow strip coming from the AC reg and getting very hot?

Have took out all the wiring to check and it all seems fine not earthing anywhere I can see

Plus i forgot to say the horn is not working either

Anybody got any ideas?

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I don't know about XRs, but with KTMs AC powers both the headlight and taillight on the stock enduro models.

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i think the same thing. my 85 xl600 head light and tail light both run off a/c. i recently replaced a/c regulator, was blowing bulbs.

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This has me puzzled, should I be getting AC volts coming from the head light and tail light? or should i be getting DC volts

anybody got any ideas

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XR'r's only use ac current. A rectifier is used to convert a/c to d/c to charge a battery, but since xr'r don't have a battery there was no need to add the rectifier. The regulator contols the voltage level holding it to a constant 14 volts (guessing) regardless of engine rpm. Stators make alternating current. XL's need a rectifier to charge the battery. I don't know what else on XL's use dc or ac current. David

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XLs dont have a split supply like KTMs do. The entire output of the stator is rectified to DC. The XRs simply have an AC regulator and 14V sounds about right.

KTMs have a coil that is regulated AC for the lights and another that is rectified to DC to charge the battery.

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XR'r's only use ac current. A rectifier is used to convert a/c to d/c to charge a battery, but since xr'r don't have a battery there was no need to add the rectifier. The regulator contols the voltage level holding it to a constant 14 volts (guessing) regardless of engine rpm. Stators make alternating current. XL's need a rectifier to charge the battery. I don't know what else on XL's use dc or ac current. David

Ah but in australia all XRs have DC power as well as AC power. AC rightly powers the lights and AC power is what comes out of the motor. DC power fuels your horn etc.

BTW XRs in australia do NOT have batteries - we have our bikes homologated for the road off the showroom. DC is needed to power the horn and blinkers in particular. The lights can be run off AC power but you still need a regulator.

US model XRs have no DC regulator so their wiring harness is smaller and lighter than ours. In the US though when you convert for road use, you have a crazy law that requires a battery be fitted (presuambly to power a break light???) so that requires DC power.

I think you're mis plugged something. AC power is pretty simple.

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Ah but in australia all XRs have DC power as well as AC power. AC rightly powers the lights and AC power is what comes out of the motor. DC power fuels your horn etc.

BTW XRs in australia do NOT have batteries - we have our bikes homologated for the road off the showroom. DC is needed to power the horn and blinkers in particular. The lights can be run off AC power but you still need a regulator.

US model XRs have no DC regulator so their wiring harness is smaller and lighter than ours. In the US though when you convert for road use, you have a crazy law that requires a battery be fitted (presuambly to power a break light???) so that requires DC power.

I think you're mis plugged something. AC power is pretty simple.

God wish you where on my side of the world, bought it to a bike shop and they were talking like they had there heads up there arse, they haven't got a clue

anyway here's to another day of messing around with wires, good thing i've a few days off work

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Funny you guys should mention this . LOL I spent a bunch of time making a little adapter to plug in to stock xr600r rear bulb holder for the usual 1157 bulb which I now know doesn't work ( ac I guess , right? ) Any ways I went back to the 904 bulb. Burns bright , but I use a resister under seat to cut down power so it looks like a running light then the presure-switches from front and rear tie back into sytem down stream from resister as to give full power and thus bright brake . BTW I put a double contact in front assy to accept a bulb from a banshee quad .( much more available and cheaper ) Also nice for back up in case of burn out , I can just replug in other hi/lo filement. :)

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Thats kind of strange about the 1157 bulb not working with AC. In my bike, AC runs a 1157 bulb just fine!

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Thats wierd . After it didn't work on bike, I took out and tried on car battery & worked fine . I put 904 bulb in bike and it now works fine . But not the 1157 ? Good way to make a blonde dizzier ! You guys with the 1157 have a dual sport kit? :)

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