Longer Starter Motor Cable

[Azul the Cat]

I'm finally getting around to doing the wiring on my project '77 GS750, and I am using the Revival Cycles starter motor relay. I have the relay all nice and situated in my new electrical tray, but now I need a longer cable to power the starter motor. Any ideas on where to get one, or what is needed to make one?

[Rich82GS750TZ]

I'd just go to the hardware store. Take the wire with you, buy a length of similar gauge wire long enough. Places like Lowe's and some better HW stores sell wire by the foot so shouldn't need to buy a whole spool. Get appropriate size lugs and crimp and solder, then heat-shrink wrap.

[Grimly]

16mm2 welding cable.

Buy one of these, too - you'll use it in future.

https://www.amazon.com/TEMCo-Hammer-Crimper-Tool-Warranty/dp/B00E1UUVT0/ref=sr_1_2?dchild=1&keywords=battery+crimp+tool&qid=1597349099&sr=8-2

[Azul the Cat]

Thank you both!

[Brendan W]

Don't forget the return cable. It gets forgotten and probably causes more issues.

[Azul the Cat]

Don't forget the return cable. It gets forgotten and probably causes more issues.

Can you tell me more about this return cable? All I see on the bike, and the wiring diagram, is the one cable coming from the starter motor.

[Brendan W]

Can you tell me more about this return cable? All I see on the bike, and the wiring diagram, is the one cable coming from the starter motor.

The current going to the starter has to get back. The return cable comes back from the crankcase to the battery negative.
Have a look at the back of the crankcase in front of the swung arm pivot or just follow it down from the battery.

[Azul the Cat]

I thought that was the function of the starter grounding through it's mounts to the engine. Would grounding the battery to the frame do the same thing?

[bwringer]

Yes, the starter grounds to the engine through its mounting bolts, but you also need that ground cable from the battery negative directly to the engine to ensure reliability and full cranking power. Don't just depend on one frame ground to make its way through the engine mounting bolts.

FWIW, I've found that GS starter/ground cables seem to be some metric gauge between 8 and 6AWG. Since metric wire is well-nigh unpossible to find here in the retro USA, I use 6AWG when I need to make cables. There's an electronics supply place near me that had some nice double-coated stuff that's extremely durable, along with nice thick terminals and a crimping tool.

Most such stranded wire you find in hardware stores has very large strands and is very stiff and difficult to work with. It'll certainly do the job, but if you can find finer stranded stuff it'll be a higher-quality experience all around.

[Baatfam]

I thought that was the function of the starter grounding through it's mounts to the engine. Would grounding the battery to the frame do the same thing?

In theory, yes, provided the mounting points are paint and grease free.
In reality, you want a good, reliable ground from the motor to the negative terminal.

I just ran down to get a picture of mine, and looking at the photo, I am glad you brought this up.
Looks like I need to pick up a new cable, myself.

[Azul the Cat]

Got it. I'll run an extra ground cable from the crank case back up to the negative battery terminal. Thanks for the picture!

[Jhurt]

Definitely use the welding cable. It’s more finely stranded and easier to work around bends and such. It’s perfect and you can but red or black. I got mine from amazon along with the terminal ends. I used the revival kit as well, quite handy.

[Baatfam]

Isn't the OEM ground cable still available from Suzuki?
I know I bought the positive side a few years ago.

[Rich82GS750TZ]

Pretty sure they are still available for most GS's, I've bought some. But I'm thinking the OP has relocated most of the electrical components to somewhere other than where a stock length wire could reach. Could be wrong.

[bwringer]

Bob, that is a beautiful and well-lit close-up of crusty moto-grunge with excellent color balance. You just can't help yourself, can you?


Yep, OP has some sort of custom thang happening and will probably have to make cables.