75 GT550 | Not getting power past the key! Please Advise!

All to do with wiring, charging or just trying to figure out whats gone wrong.

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GT550_First-Timer
Still in the Driveway
Posts: 7
Joined: Mon Nov 19, 2012 8:37 pm
Country: USA
Suzuki 2-Strokes: 1975 GT550
Location: Western NC

75 GT550 | Not getting power past the key! Please Advise!

Post by GT550_First-Timer »

Hello Everyone,

I recently bought my first motorcycle, a 1975 GT550. I have owned and restored a few cars so I am not entirely in the dark. But slowly working my way through this new toy.

Thus far: I have installed a brand new charged battery, fresh spark plugs that are gapped appropriately, recoated my rusty tank with caswell two part sealer, installed a fresh petcock, new fuel filter, new air filters, I have oil in my oil tank, gapped the points within their tolerance, and the bike kicks over freely but doesn't start up and run.

Today, I intend to lightly sand the points and cleanup all grounds.

The issue: I have not seen any response anywhere when turning the key to the on position. No lamps (could be broken bulbs), no horn, no starter, no lights, no gauges jumping. When I tried to kick the engine over with key on and starter switch to the RUN position it spins over. upon giving throttle and kicking it seems to get more throaty like it really wants to start but something is holding it back.

I have followed the power with a multimeter from the battery through the starter relay, past the fuse, and both hot wires make it up to the ignition switch. I have NOT successfully found power anywhere past the key.

Can someone tell me how to open the ignition switch and clean the contacts?
Also, where specifically should I look for power next with key turned to ON position?


http://instagr.am/p/Q7za9Bveph/

Bike has been chopped and bobbed in the past by a certified welder. Though, not a certified upholsterer. :up:
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tz375
Moto GP
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Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: 75 GT550 | Not getting power past the key! Please Advise

Post by tz375 »

There are other more qualified than I to answer electrical questions, but I'd start with the switch, a multimeter and wiring diagram.

Disconnect the switch at the plug and test the circuits to see if the switch is making all the correct connections. 0One quick and dirty technique is to flush the switch through the key slot with wd40 and turn the key back and forth many times, then flush again and re-test. That isn't the same as opening it up, but it's also less likely to lose the small balls and springs inside.

IIRC, in the center (ON) position Red connects to Orange and Gray connects to Brown.
GT550_First-Timer
Still in the Driveway
Posts: 7
Joined: Mon Nov 19, 2012 8:37 pm
Country: USA
Suzuki 2-Strokes: 1975 GT550
Location: Western NC

Re: 75 GT550 | Not getting power past the key! Please Advise

Post by GT550_First-Timer »

tz375 wrote:Disconnect the switch at the plug and test the circuits to see if the switch is making all the correct connections.

IIRC, in the center (ON) position Red connects to Orange and Gray connects to Brown.
I do in fact have the wiring diagram, per original owner's manual. Have the multimeter as well.

Still not much of an electrician. Would I be checking the plug connections on the battery side or on the switch side?
I found that there is power by the Red wire on the battery side. Should gray or brown have power?
GT550_First-Timer
Still in the Driveway
Posts: 7
Joined: Mon Nov 19, 2012 8:37 pm
Country: USA
Suzuki 2-Strokes: 1975 GT550
Location: Western NC

Re: 75 GT550 | Not getting power past the key! Please Advise

Post by GT550_First-Timer »

**update** I sprayed contact cleaner into the ignition switch and toggled it a bit. I now have power to my cluster, horn, and lights when the key is in the middle of the three positions.

However, when I toggle the key to the right position, I lose the lights and horn. Is the right key position, as I understand it, to start the bike with the starter switch??

I am about to disassemble my starter switch and attempt to clean the contacts as advised by my local cycle shop. "City Cycle Supply in Asheville, NC."

In which key position am I intended to start the bike with the starter button by the grip?
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tz375
Moto GP
Posts: 6204
Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: 75 GT550 | Not getting power past the key! Please Advise

Post by tz375 »

Left is OFF
Center is ON
right is PARK

In the Park position, the connection IIRC is red (battery) to brown (tail and park lights)

The bike runs in the Center spot. If you have power to the light now, toggle some more and then repeat that process on the run-stop switch.

You may have to strip the START button to clean the contacts but watch where the tiny spring flies off to. It usually vanishes into a black hole that opens up when the switch is disassembled. Funny how that works. Some sort of warp in the space time continuum linked to pulling switches apart. The odd thing is that they may reappear in a similar location at a later time, but they are not in this space-time coordinates for the longest time. :shock: :? :lol: :lol:
GT550_First-Timer
Still in the Driveway
Posts: 7
Joined: Mon Nov 19, 2012 8:37 pm
Country: USA
Suzuki 2-Strokes: 1975 GT550
Location: Western NC

Re: 75 GT550 | Not getting power past the key! Please Advise

Post by GT550_First-Timer »

tz375 wrote:Left is OFF
Center is ON
right is PARK

In the Park position, the connection IIRC is red (battery) to brown (tail and park lights)

The bike runs in the Center spot. If you have power to the light now, toggle some more and then repeat that process on the run-stop switch.

You may have to strip the START button to clean the contacts but watch where the tiny spring flies off to. It usually vanishes into a black hole that opens up when the switch is disassembled. Funny how that works. Some sort of warp in the space time continuum linked to pulling switches apart. The odd thing is that they may reappear in a similar location at a later time, but they are not in this space-time coordinates for the longest time. :shock: :? :lol: :lol:
Ive heard tell of the black hole for little vanishing springs. *wrapped the switches in a bag while disassembling... went smoothly.*

After spraying PJ1 professional contact cleaner into the ignition switch and starter switches I toggled both on and off many times and was able to restore power to all controls. my horn, lights, cluster, and starter are all getting power. The starter turns but I still have not been able to fire it up.

New thread for my continuing electrical scouring:
http://www.suzuki2strokes.com/forum/viewtopic.php?f=29&t=7827

Back to the garage. Thanks MotoGP
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