electrical problem
- Mudfacetony
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electrical problem
Now here is a good one.
A copule of weeks ago my Mk3 started with a small electrical problem. When I put the indicators on, the back light would also flash (at first you could hardly tell), which is now really pronunced.
To add to this, I as up in Scotland on Tuesday and all of a sudden I could hear something like arching and the bike started to miss fire. I thought it was because it was very cold (-5) but it sarted doing it again yesterday when it was +6. Thismiss firing is intermittant.
I have checked the back end by removing the indicators and using a spare rear light and the problem of the flashing back light is still there. I have also inpected the wiring under the seat (it needed loads of cleaning) and I have inspected the wiring behind the headlight and cannot see anything.
I can't replicate the misfiring/arching but I'm sure it will still be there.
Can anyone help before I start throwing a big hammer at the bike?
A copule of weeks ago my Mk3 started with a small electrical problem. When I put the indicators on, the back light would also flash (at first you could hardly tell), which is now really pronunced.
To add to this, I as up in Scotland on Tuesday and all of a sudden I could hear something like arching and the bike started to miss fire. I thought it was because it was very cold (-5) but it sarted doing it again yesterday when it was +6. Thismiss firing is intermittant.
I have checked the back end by removing the indicators and using a spare rear light and the problem of the flashing back light is still there. I have also inpected the wiring under the seat (it needed loads of cleaning) and I have inspected the wiring behind the headlight and cannot see anything.
I can't replicate the misfiring/arching but I'm sure it will still be there.
Can anyone help before I start throwing a big hammer at the bike?
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Re: electrical problem
Hi Tony, Hhmme, could it be water in the harness, the current could be flowing through a wet joint, and livening up the rear lightMudfacetony wrote:Now here is a good one.
A copule of weeks ago my Mk3 started with a small electrical problem. When I put the indicators on, the back light would also flash (at first you could hardly tell), which is now really pronunced.
To add to this, I as up in Scotland on Tuesday and all of a sudden I could hear something like arching and the bike started to miss fire. I thought it was because it was very cold (-5) but it sarted doing it again yesterday when it was +6. Thismiss firing is intermittant.
I have checked the back end by removing the indicators and using a spare rear light and the problem of the flashing back light is still there. I have also inpected the wiring under the seat (it needed loads of cleaning) and I have inspected the wiring behind the headlight and cannot see anything.
I can't replicate the misfiring/arching but I'm sure it will still be there.
Can anyone help before I start throwing a big hammer at the bike?

Mike
VFORCE REEDS-MUGEN HEAD AND BARREL-WHITE POWER-ALL ON MY WISH LIST!!
- knackeredMk1
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Re: electrical problem
hi tony is the headlamp coming on dim when you use the indicators ? if so then the rear indicators are finding a earth through the tail light & travelling up to the headlamp & then down to earth try connecting a wire to a clean part of the frame & the other end to the earth wire feeding the rear light & indicators
chris
chris
if it aint broke then dont fix it !
- Mudfacetony
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Re: electrical problem
Just for info, in case anyone gets a similar problem, the final solution to this was to change the condensor (not sure this was a problem but changed it anyway) and also changed the rectifier and all appears to be sorted.



- knackeredMk1
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Re: electrical problem
The symptoms you listed were classic for a short in the wiring. You may have moved the wires or dried them out during your investigation but I'm sure that the capacitor and reg/rec were not responsible for the original problem.
Re: electrical problem
I would say bad earth! might be worth checking as some where the parts you mentioned might have something to do with the earth either, directly or indirectly
- Mudfacetony
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Re: electrical problem
Definitley not just bad earth. After 2 months of "drying out" and a trip to the sparky the problem was still there until the rctifier was shown to be dead and changed.
- knackeredMk1
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Re: electrical problem
Having reread the original problem was it that the back light came on when the indicators were on or that the back light (that was already on) flashed when the indicators were on
.
If the second I can entirely see why the faults lay with the reg/rec and maybe capacitor.

If the second I can entirely see why the faults lay with the reg/rec and maybe capacitor.
- jontymiller
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Re: electrical problem
I agree with Knackered there should be a short in the wiring!
- jm38
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Re: electrical problem
my mk 2 started to pop and fart at the end of 3 long straights on way home as i was braking for an s bend it ground to a halt so i wiggled all easy to get at wires put it on reserve and turned off the lights and it restarted and rode as good as ever .next run i started it and noticed the lights dimming as i revved it but just thought it would clear later.
it started to die under braking or if i indicated so again i switched off the lights and all was well for the rest off the run.
i stripped the bike to find what i thought would be a loose connection but could not find anything so i took off the rectifier and tested it one set of diodes had died .a replacement was concocted from an other bikes (kwaka)i think but it would not run untill i turned the lights off again ,then it would fire and miss fire and miss fire and miss ,i also noticed the neutral light was blazing verey brightly .
i have ordered another from ebay (39.99)and will update when it arrives and i have tried it out.a new replacement can be obtained from electrex for £90 .
it started to die under braking or if i indicated so again i switched off the lights and all was well for the rest off the run.
i stripped the bike to find what i thought would be a loose connection but could not find anything so i took off the rectifier and tested it one set of diodes had died .a replacement was concocted from an other bikes (kwaka)i think but it would not run untill i turned the lights off again ,then it would fire and miss fire and miss fire and miss ,i also noticed the neutral light was blazing verey brightly .
i have ordered another from ebay (39.99)and will update when it arrives and i have tried it out.a new replacement can be obtained from electrex for £90 .
- knackeredMk1
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Re: electrical problem
What you describe sounds very much like there is a short in the wiring loom to the frame in the lighting circuit,
- helisupp
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Re: electrical problem
Possibility of mud, water in the rear light connection where wires are connected to the light assy.
One of mine was full of mud and causing problems.

One of mine was full of mud and causing problems.
- jm38
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Re: electrical problem
well the replacement rectifier arrived yesterday ,i plugged it in and fastened it up and i now have a runner with lights that dont dim either braking or indicating .i did find the rear light connector was dirty could this may have started the fault that killed the rectifier ?
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Re: electrical problem
Alright jm, whereabouts in preston are ya?