Hello, I new to this world so please have patience with me . Thought I would try to get it started before continuing to deep into the restoration. However, nothing happens when connecting a battery to it (i.e. no lights, no spark) and I notice some obvious places in the wiring loom where "parts" are missing. I just ordered the Haynes manual, but maybe you can help me out while waiting for it? I didn’t find a wiring diagram for the GT125 in the links, but I guess the GT185/GT250 wiring is similar except for maybe the electric starter?
Item 1: Is there some component missing here (guess so), or should they just be connected to each other (guess not)?
Item 2: Where should this go?
Item 3: Where should this go?
I would be really grateful if you could help me out.
Best regards, Jake
GT125 -74 missing items/wiring
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Re: GT125 -74 missing items/wiring
Welcome to the forum.
Don’t think the GT125 was sold in the US. I found very little info about it.
A good place to start would be some manuals. Did a quick eBay search & found useful manuals.
A New Zealand seller has good reproduction parts manuals: https://www.ebay.co.uk/itm/364139514311
The GT185 has a generator/starter & the GT250 has an alternator. So their wiring setup would differ.
A GT185 wiring diagram is available on SuzukiCycles.org & is here:
http://www.suzukicycles.org/GT-series/index.html
Don’t think the GT125 was sold in the US. I found very little info about it.
A good place to start would be some manuals. Did a quick eBay search & found useful manuals.
A New Zealand seller has good reproduction parts manuals: https://www.ebay.co.uk/itm/364139514311
The GT185 has a generator/starter & the GT250 has an alternator. So their wiring setup would differ.
A GT185 wiring diagram is available on SuzukiCycles.org & is here:
http://www.suzukicycles.org/GT-series/index.html
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Suzuki:
GT750 2x75
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T500 69 project & 73 project
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Re: GT125 -74 missing items/wiring
i would say the yellow goes to yellow - main beam wire or idiot light wire. and grey to grey - idiot lights wire. can't make out the 2nd photo very well, but a red wire is ALWAYS live with the battery connected. the black/white wire in the 3rd photo goes to earth, as do all black/white wires
cheers, dd.
cheers, dd.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
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Re: GT125 -74 missing items/wiring
Thanks a lot for answering, guys!
jabcb; Thanks, will check out the link. I have a Haynes manual on the way, hopefully it's good.
dd; Thanks, I guess the colors in the photo are a bit misleading, they are really like yellow/orange and blue:ish (left side) and yellow/orange and green:ish (right side). So you think that they should basically be connected? Was there like a fuse holder there, or why were the broken out of the main loom (or maybe someone modded it)? Ok, the black/white should be grounded, didn't find a good place where it should be connected.
Also, I noticed that the is no horn anywhere so they might be related to that as well. I will do a round with the multimeter and see what I can discover.
jabcb; Thanks, will check out the link. I have a Haynes manual on the way, hopefully it's good.
dd; Thanks, I guess the colors in the photo are a bit misleading, they are really like yellow/orange and blue:ish (left side) and yellow/orange and green:ish (right side). So you think that they should basically be connected? Was there like a fuse holder there, or why were the broken out of the main loom (or maybe someone modded it)? Ok, the black/white should be grounded, didn't find a good place where it should be connected.
Also, I noticed that the is no horn anywhere so they might be related to that as well. I will do a round with the multimeter and see what I can discover.
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Re: GT125 -74 missing items/wiring
horn wires are dark green from the horn push and orange - live - from the loom. push the horn button and the green wire earths, making the horn beep
cheers, dd.
cheers, dd.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
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- Still in the Driveway
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- Suzuki 2-Strokes: GT125 -74
Re: GT125 -74 missing items/wiring
If I interpret the wiring diagram correctly, the loose wire pairs corresponds to the horn as you say dd, and the other pair should go to a turn signal relay if I'm correct. So none of them should be the show stopper, right?
I didn't have much time for debugging this weekend, but I could at least see that the orange wiring has contact with the earth at all times, no matter of the ignition key state. So I need to figure out why that is... bad ignition lock? some orange wire with bad insulation scraping against the frame?
I didn't have much time for debugging this weekend, but I could at least see that the orange wiring has contact with the earth at all times, no matter of the ignition key state. So I need to figure out why that is... bad ignition lock? some orange wire with bad insulation scraping against the frame?
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Re: GT125 -74 missing items/wiring
If I disconnect the connector that goes to the two ignition coils, the orange and earth does not have contact any longer. Does this mean that some of the coils have a problem?
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Re: GT125 -74 missing items/wiring
If you put paper between the points, you can plug in the coils and they should clear.
The coils are more or less transformers and when the points close, it completes the circuit, and will show a short.
The coils are more or less transformers and when the points close, it completes the circuit, and will show a short.
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Re: GT125 -74 missing items/wiring
Thanks a lot for all your help. Good news - there's spark! At least on the right cylinder . The left ignition coil looks suspicious, should I assume that it is broken?
What the problem was? I don’t know, honestly. The bike fixed itself while I was checking for damaged cables, cleaned out connectors, earth connections etc.
What the problem was? I don’t know, honestly. The bike fixed itself while I was checking for damaged cables, cleaned out connectors, earth connections etc.