OzVMX Forum
Clubroom => Tech Talk => Topic started by: adam.m on April 13, 2013, 10:02:18 am
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I wanted to tidy up the wiring and get rid of anything unnecessary. So I cut away the wiring loom that goes to the rear of the bike but in the process, severed something essential to the running of the bike. So a friend went through and found an earth wire that wasnt connected, so he gathered all the earth wires together and earthed them off the negative on the coil. Bike ran but gave me one hell of a shock off anything attached to the frame.
If I take all the earth wires and earth to the frame, no go.
So it seems the coil needs an earth, but earth to what ???
If anyone has an XL500R , I would appreciate a photo of the coil on the bike and related wiring.
Thanks
PS. Just working on an image to better explain things, will post shortly.
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mate,disconect your friend ;D ;D, :P
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lol, yea :)
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(http://sphotos-b.ak.fbcdn.net/hphotos-ak-prn1/892970_4603810140364_397119340_o.jpg)
(http://sphotos-d.ak.fbcdn.net/hphotos-ak-frc1/905529_4603810620376_434499506_o.jpg)
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So, if I gather all the green earth wires together and earth off the coil it runs but misses and shocks.
If I gather them together and earth off the frame it wont run.
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ok,heres what i got on my MV,(using same basic honda CDI)
ignore/disconnect rec/reg wires (for now)just incase??
your #2 green from box goes to the coil as earth
cant see ?,should be black out of box to kill switch,to your blk/w wire,then out of switch to earth green (frame),disconnect till sorted??
in your piccie ,is that blk/w (blk/y) going into double green,a no no?
my trigger wires blue/y into box,but y(ellow) goes to frame earth,(not coil earth)
r/blk from stator to box is alls needed to charge the C in CDI (top r/h wire)
imediately below #2 green,what colours that?,yours is 6wire box,diagram shows 5? (mines 5)
hth?,cheers mick
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Thanks Mick
Im not sure I follow completely but one thing you said was the CDI green earth wire should goto the coil earth ?
I think this is my biggest problem, knowing where to earth the coil. All the other earth wires should be ok earthed to the frame ?
I forgot to mention that it doesnt run a battery so shouldnt need to disconect rec/reg wires ?
Shouldnt need to worry about any of the other wires apart from the green earth wires, nothing else was touched.
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(http://sphotos-f.ak.fbcdn.net/hphotos-ak-ash3/s480x480/555021_4605189054836_1296487013_n.jpg)
Here is a close up of the area in question.
It shows the green from the coil (coil earth) joining the regulator green (reg earth) and joining onto a common earth. But I need to figure out how to pick up that common earth, and what kind of earth it is.
Seems to be two kinds of earth, ground earth and frame earth.
Im wondering what the symbols circled in red mean, and im guessing the purple circle is earth, but what earth ???
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I think Micks on it, In towards the bottom of the photo 2 wires to the left of Number 4 there is a black and yellow pluged into a green, so when you earth everything you short out the circiut, that wire should go through the kill switch and would the short the circiut when kill switch is used.
I think
Noel
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Ah, ok, thanks guys, now I get you (i think) ;D
If this is the case, ive been barking up the wrong tree.
Will investigate
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Nope, thats not actually the case, just an optical illusion, the black/yellow actually passes behind the green :'(
Here is the wiring diagram again, this time ive gone through and traced every green wire and they all connect to a central earth, marked with the red circle. So in theory , grouping all the earth wires together should have worked ? But they shouldnt have all been joined together and earthed onto the coil earth. The coil earth needs a separate earth back to the frame. Then the other earths can goto a frame earth aswell.
Another question is, what are the symbols ( circled red in the previous image ) , and how do they effect things ???
(http://sphotos-h.ak.fbcdn.net/hphotos-ak-prn1/893619_4605266856781_2101932250_o.jpg)
http://sphotos-h.ak.fbcdn.net/hphotos-ak-prn1/893619_4605266856781_2101932250_o.jpg (http://sphotos-h.ak.fbcdn.net/hphotos-ak-prn1/893619_4605266856781_2101932250_o.jpg)
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Thanks so much for your help guys ;)
Im just wondering if anyone can tell me what the symbols are circled in red ?
(http://sphotos-f.ak.fbcdn.net/hphotos-ak-ash3/s480x480/555021_4605189054836_1296487013_n.jpg)
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i think the symbols shown in red look to be a lug ( a cable lug that would be connected to the frame or "earth")
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Thanks Hoony , like one of these im guessing.
(https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQPM3Y1BWOAbBA2ogonGskM2NKtgyYQ2rLvobF9uiqWW9Hm5SNQ)
But the mystery remains, everything is still ultimately connected to the same earth ??? so why would it indicate the extra earth points and are they earth or frame earth ???
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Try connecting a wire from the coil earth connection to your bulk earth wires and then connect that bulk earth wires to the frame. This will effectively be connecting the frame and coil earth together and then connecting them both to the frame this will bring everything to 'earth' potential that should be.
It sounds like the HT spark is actually returning to the coil earth through the frame and then via some other device like a globe or switch hence the frame is at high potential due to the resistance of that device while the engine is running (result zappo).
People think that any earth wire is at zero volts but it is only at zero volts when connected to the negative or earth of the system even then it is only a relative zero voltage for that system.
Your system needs some sort of load to make the regulator work. Later bikes had a large capacitor to act as load so the regulator did not fail oriiginally in your system the battery served this purpose without a battery or capacitor to allow the regulator to do its job the regulator will burn out in very short time (like seconds not hours).
Hope this helps. The wiring diagrahm is useful but trying to fault find without looking at the bike is almost impossible particularly as you have cut wires without indicating what they were. These types of experiments should be done one wire at a time and test between or better still work out what you are 'disconnecting' before doing so. I know it is a bit late for that.
If this does not fix it then you need to find which wires you cut to see what they actually were
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try running a separate earth wire from your bunch of earths to the engine cases as well since that's where the cdi is getting its high voltage from [100v + ac] and the spark plug earths to the head as well.powder coating/paint/rusty/oily engine mounts make it hard to get to where it wants to go which is back to the bunch of earths.had a new xr200 in for its 1st service and whilst running I touched the frame earth coz the seat was off at the time,wow it gave me a decent boot :o coz the little jap didn't clean the powder coat off where it earthed but didn't boot me after I filed it back to bare metal. ;)
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Think I got it sorted.
Coil and regulator earths to (1) frame earth, and all other earths to (2) frame earth.
Runs with no shocks. Havent ridden it yet for the final verdict.