81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

Was running good and now if you hit either brake it kills the engine. I've stripped the whole harness and haven't found anything. The headlight works but the rear running light isn't working but the brake light will work, but it also kills the engine when you hit the brakes? Any help would be greatly appreciated. Also this is the silver bullet model with turn signals if that helps. The turn signals have never worked but now it won't run if you hit the brakes, fml lol Thanks

Re: 81 tomos a3 cuts of when you hit either brake????

Did this happen after rear light stopped working?This may do nothing but why does rear light not work? Try new bulb.

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

Correction,,, all lights now work, headlight, rear running light, and brake light. Still when I hit the brakes either front or rear the bike kills like a kill switch. I'm stumped.

Re: 81 tomos a3 cuts of when you hit either brake????

the wire from the stator goes directly to the brake light switches to ground.

applying either brake opens the circuit, removing the ground.

there is a T wire that feeds off to the brake light bulb, applying the brakes leaves the bulb as the only ground (for the ignition)

i hate how the taillight is grounded to the back fender by a bolt, which is then bolted to the frame, to the motor.

this makes multiple spots for poor connections to act up.

i run the ground from the taillight to the coil mounting stud, done.

also wrong wattage bulb, taillight wires switched need to be considered.

i'd run a ground overlay from the motor to the tail ground, then the brake light wire plug to see if the problem is eliminated.

also check with the lens off to see if the bulbs are acting properly, not glowing dimly when they shouldn't be, etc.

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

Bump for more info please. I still haven't figured it out

Re: 81 tomos a3 cuts of when you hit either brake????

simple checks:

on the stand, use your foot to stop the back tire from spinning.

stays running? this eliminates the clutch as a problem.

pull the taillight lens, headlight off, does either bulb glow at all?

headlight on, does only 1 bulb light, is it properly bright, is the other glowing at all?

clip a length of wire to the motor metal, touch the other end to the spade connecting the taillight to the fender ground, hit the brakes, does it stall?

now touch the wire to either of the other 2 spades and apply brake, does it stall?

if all 3 ground overlays still stall the bike, you have a bad connection from the stator to the brake light.

if touching any of the 3 spots allows the motor to stay running with the brake on, report back which wires.

also if any of the bulbs are lighting "funny"

what the wattage (part number) of the bulbs are, and if you can see the 5w or 10w written on the taillight housing.

also post the colors of the brake switch wires (4) and the taillight (3) so i can give you specifics.

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

Haven't tried the ground overlays but it idles even when I stop the back tire from spinning. It drives fine it's just when you brake it cuts off.

I tried disconnection the pigtails to the turn signals and rear lights and it still cuts off. So does that mean it's a wire from the stator to the front switches?

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides Wrote:

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> I tried disconnection the pigtails to the turn

> signals and rear lights and it still cuts off. So

> does that mean it's a wire from the stator to the

> front switches?

it means there's a break in the circuit from the stator to the brake light back to ground.

in lieu of a running ped, i use a 9v battery to test bulbs and wiring, find the stator wire feeding the brake light, and connect the battery between that and motor ground, bulb should glow.

repeat at the taillight connector to see if it's the ground or the socket / bulb.

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

Ok so in the rear I have

(Brown) ground wire

(Green) power for rear running light

(Grey) power for stop light

Taillight wires were poorly connected so I thought that was the problem but it wasn't. Still cuts off when I apply the brakes.

I'm using a test light grounded and when I hit the brakes the grey wire has power. Really bright power compared to the (green) running light wire.

When I hit the brakes I felt a small shock in my fingers so I know it's a bad wire somewhere I'm just not sure where. I'm getting I'll with this damn thing.

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

Pic of wire block

image.jpg

Re: 81 tomos a3 cuts of when you hit either brake????

Double Trouble Dan /

The easiest way to trace the shorted wire is with a continuity or ohm tester.

disconnect wires one by one and do a continuity to ground check.

That should isolate the grounded wire.

My guess is that either the spot where it comes from the coils through the cover has rubbed off the insulation, the lighting coil itself is shorted , the brake light socket has shorted ,a brake switch , or the stop switch .

To check the brak switches, Disconnect one wire from a brake switch and try to hit the lever with the engine running on the stand.. reconnect it and try the other wire.

Now do the other side the same way.

Patience , you'll get it.

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

Ok the blue wire from the stator has no power until I hit the brake. Is that normal?

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides Wrote:

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> Ok the blue wire from the stator has no power

> until I hit the brake. Is that normal?

blue connects to grey, connects to brake switches to ground, pulling the brake removes the ground, the test light you're using is simulating the brake bulb, so yes, it is normal.

>when I hit the brakes the grey wire has power.

same as the blue wire.

you never replied if the taillight is acting "normal" so here's my diagnosis:

you have the 3 wires from the taillight mixed on the plug on the back of the light.

the taillight is grounding thru the grey wire via the brake switches.

check where the brown wire feeds to the copper contacts inside the taillight, it should connect to the side of both bulbs, trace it out.

also see if you can get the brake bulb to light with the 9v battery on the grey to brown on the back of the taillight.

barring that, it's a grounding issue at the fender to motor.

Re: 81 tomos a3 cuts of when you hit either brake????

♣Slew Foot♣ /

broken ceramic resistor hidden in tail light braket it is inside of it it has two pry points to access the resistor.

Re: 81 tomos a3 cuts of when you hit either brake????

if the resistor is no good, just bypass it

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

I checked the connection of the 3 wires in the taillight and they were loose so I got excited. It was a pain in the butt,,,, but I got them securely in place and still the same result.

The resistor looks fine and the solder looks good. I'm gonna try and bypass it later today just to make sure.

Re: 81 tomos a3 cuts of when you hit either brake????

the only reason that resistor is there is for when your brake bulb burns out.

it essentially jumpers across the brake bulb contacts, keeping the connection when the bulb goes open.

without a working brake light circuit, bulb or resistor, the ped will shut off when brake switches are applied.

sorry you're struggling

Re: 81 tomos a3 cuts of when you hit either brake????

Derrick Oyervides /

So where exactly is this rear fender ground?

Maybe someone could just give me a call and explain over the phone better. I've tried everything and getting flustered.

864-630-2715 if anybody wants to call and lend some over the phone advice would be greatly appreciated. I'm sure it's something small and I'm just overlooking

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