GT250 - more wiring Q's

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daxman
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Suzuki 2-Strokes: A100 GT250 & 4t Yams!
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GT250 - more wiring Q's

Post by daxman »

Hi All

Well I've patched up the loom (no regulator yeT) , and started to fit a temporary (?) 7" replacement headlight (purists look away now) on some new brackets. I foolishly failed to take any pictures of the loom routing however. The main part is still on the bike but I'm wondering if anyone has a picture of the arrangement in and around the headlight.

Cheers
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ConnerVT
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Re: GT250 - more wiring Q's

Post by ConnerVT »

In most headlight buckets, it typically looks like this:

Image
Vintageman
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Re: GT250 - more wiring Q's

Post by Vintageman »

ConnerVT :lol: :lol: :lol: :lol:

Also, how do you post pics here? Is that really a link to some other hosting web site


Daxman,

I think you are asking how to connect the various wires from cables that join in the head light bucket (couple main harness, Instrument lights, left and right hand controls etc.).

I just put a T350 back together without pics (lost them) and it hand been a while. 98.4 % is just just match up wire colors colors. Also wiring diagram helps... to figure what couple remain

If you get stuck I could pull my (76 GT250 and 74 GT250) headlight out and takes pics... bike in storage packed like a sardine, but maybe this weekend....

I am not sure how to post pics (question above). Ever since Photobucket changed I haven't found another free solution. Maybe I just need to pay $
Current Bikes
74 GT250 (T350 upgrade),
76 GT250 (T350 upgrade),
71 T350,
70 T350,
74 GT380,
75 T500,
73 GT550,
75 GT750,
72 Yamaha DS7 (R5 upgrade),
77 Yamaha RD400 (Daytona Cyls),
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ConnerVT
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Re: GT250 - more wiring Q's

Post by ConnerVT »

Just a picture stolen, errr, hot linked from another site.

Right-click
Copy Image Location
Paste it between the [ img ] [ /img ] thingies

Code: Select all

[img]https://st.hotrod.com/uploads/sites/21/2010/08/1008phr-02-o-american-autowires-classic-update-kit-rat-nest.jpg?interpolation=lanczos-none&fit=around%7C660%3A495[/img]
dollydog
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Re: GT250 - more wiring Q's

Post by dollydog »

vintageman, try this. dead easy to use and free. i use nothing else :)
cheers, dd.
https://postimg.cc/" onclick="window.open(this.href);return false;
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.
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jabcb
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Re: GT250 - more wiring Q's

Post by jabcb »

The wiring diagram is here. Later GT250s have a voltage regulators while the early ones do not.
download/file.php?id=826
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Suzuki:
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daxman
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Re: GT250 - more wiring Q's

Post by daxman »

Vintageman wrote: Daxman,

I think you are asking how to connect the various wires from cables that join in the head light bucket (couple main harness, Instrument lights, left and right hand controls etc.).

I just put a T350 back together without pics (lost them) and it hand been a while. 98.4 % is just just match up wire colors colors. Also wiring diagram helps... to figure what couple remain

If you get stuck I could pull my (76 GT250 and 74 GT250) headlight out and takes pics... bike in storage packed like a sardine, but maybe this weekend....
Yes just that. I can match all the connections no problem using wiring diagram. Trying to figure out the 'physical arrangement' e.g. are all the multi-way connections made inside the bowl, does the secondary loom sit entirely inside the bowl etc. using an aftermarket lamp is not ideal as I think there's less room. :roll:
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Re: GT250 - more wiring Q's

Post by Vintageman »

jabcb wrote:Trying to figure out the 'physical arrangement' e.g. are all the multi-way connections made inside the bowl,
Just give it a go. Trust me it is all color coded. And, without bucket in the way you can see clearly. For example, let's say you see 4 solid orange wires total with single male connectors each. You may see two solid orange wires each with a double female socket... start mating up colors code via male and female connectors and let me if any left over. Make sure they plug in with a nice click... you may have to reshape the female connector if too loose.

Dollydog... I'll give your suggestion a go next time. Thanks
Current Bikes
74 GT250 (T350 upgrade),
76 GT250 (T350 upgrade),
71 T350,
70 T350,
74 GT380,
75 T500,
73 GT550,
75 GT750,
72 Yamaha DS7 (R5 upgrade),
77 Yamaha RD400 (Daytona Cyls),
dollydog
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Re: GT250 - more wiring Q's

Post by dollydog »

dax, to answer a couple of your questions. yes, all the multi connectors sit in side the headlamp bowl. so does the secondary loom - i presume you mean the headlamp loom? short piec about a foot long with loads of wires and multi connectors on it? getting all the wiring back in the headlamp bowl, even on a standard gt is a pain, bloody awkward and bloody frustrating when you think you've done it, try everything and one side of the indicators don't work, because you pulled a wire out while trying to cram it all in that little space. been there, done it, several times. try it with a h4 headlamp conversion - it's far, far worse :D i use those bendable, plastic coated, steel things to hold my wiring in. they sit on the inside of the earth wire bolts and hold the wiring secure while you get the front rim on.
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.
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Re: GT250 - more wiring Q's

Post by Vintageman »

What I am assuming or saying is the headlamp bucket is simply a junction box for all the harnesses that head its way be it it from frame harnesses, left and right handle controls, Instrument panel, etc. They enter the bucket via couple holes in it all connectors join there. Tight but enough room. The wires are all color codes and connectors unique as needed.

Altogether may look daunting like ConnerVT pic exaggerates, but meant for general labors to assemble. Sure once you done a few it must be very easy.

On the GT250 the head lamp itself I think has just three wires going to a unique connector with a unique mate you need to find and click the together. Always check condition of connectors just in case corrosion which they are usually gold plated, but still worth a look see.


When you get to turn signals it may be just black wire on each and you need to look at wiring diagram to see what color wire form other harness is left or right or just take a 50 50 chance .. if wrong swap. I leave these last

The wiring diagram may also be helpful to know what color is frame/ground (for usually more than one) but again all color coded with clear mating connectors so really don't need to be an electrical engineer

I am a bit smug (or biased in understanding your question) here for I had same fear as explained on my 1970 T350, lost pics, and had no choice but to go for it. Also, all my wires and harnesses were very good and never hacked up.

I'll read response more carefully. I can take pics tomorrow I hope.
Current Bikes
74 GT250 (T350 upgrade),
76 GT250 (T350 upgrade),
71 T350,
70 T350,
74 GT380,
75 T500,
73 GT550,
75 GT750,
72 Yamaha DS7 (R5 upgrade),
77 Yamaha RD400 (Daytona Cyls),
dollydog
Yeah Man, the Interstate
Posts: 630
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: GT250 - more wiring Q's

Post by dollydog »

hi vm, i think you'll find that 3 pin connector is a 4 pin - should have red/grey/orange and brown wires to and from it. it goes to the ignition switch. red is power in from the battery, orange is power out from the ignition switch to all the ancilliarys needing power. the grey and brown are part of the lighting circuit. dead easy way to remember the indicator wiring colours. g[r]een is right indicators and b[l]ack is left. all earth wires are black with white stripe. there is a 3 pin connector in the heeadlamp, but it's for the headlamp bulb. yellow for main beam, white for dip beam and black/white is earth. the yellow wire is sometimes a double and the extra wire goes to the high beam idiot light. thankfully suzuki usually kept the wire colours the same, grey is always in the lighting circuit, dark blue is always the neutral light switch, white is the stop light switches, front and rear, etc. i love wiring :D
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.
Vintageman
Expert racer
Posts: 1483
Joined: Tue May 18, 2010 5:38 pm
Country: USA
Suzuki 2-Strokes: Suz, Yam, Honda, Kaw.
Location: New Hampshire

Re: GT250 - more wiring Q's

Post by Vintageman »

But you must agree... all is color/connector coded, plug and play, unless it was hacked up.
Current Bikes
74 GT250 (T350 upgrade),
76 GT250 (T350 upgrade),
71 T350,
70 T350,
74 GT380,
75 T500,
73 GT550,
75 GT750,
72 Yamaha DS7 (R5 upgrade),
77 Yamaha RD400 (Daytona Cyls),
dollydog
Yeah Man, the Interstate
Posts: 630
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: GT250 - more wiring Q's

Post by dollydog »

But you must agree... all is color/connector coded, plug and play, unless it was hacked up.

absolutely mate. just like building a p.c. if it doesn't fit, it doesn't go there. if it's the wrong colour, it's wrong :D
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.
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