RV125 - connecting battery

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

Moderators: oldjapanesebikes, H2RICK, diamondj, Suzsmokeyallan

Post Reply
dfa1000
Still in the Driveway
Posts: 4
Joined: Wed Aug 06, 2014 5:57 am
Country: Australia
Suzuki 2-Strokes: RV125, GXSR-750

RV125 - connecting battery

Post by dfa1000 »

Hi Everyone

First time on here, it might sound pretty silly but which wires do you connect the battery to? I am restoring an 72 RV125 and it wasn't complete when i got it and came with no battery.

I tried looking at the wiring diagram but couldn't figure it out. Is the positive wire the red wire near the rear brake light switch? If so where does the negative wire connect to.

I tried to add a photo but it says "Sorry, the board attachment quota has been reached."

Thanks,
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: RV125 - connecting battery

Post by jabcb »

All of the Suzukis are negative ground.

The wiring diagram for a 1977 RV125 is shown under the wiring diagrams topic.
Per the diagram, battery +/positive connects to a red wire which should have a fuse.
And battery -/negative connects to a black ground wire that then attaches to a good ground like on the frame.

Your 1972 RV125 is likely somewhat different than shown in the 1977 wiring diagram.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
dfa1000
Still in the Driveway
Posts: 4
Joined: Wed Aug 06, 2014 5:57 am
Country: Australia
Suzuki 2-Strokes: RV125, GXSR-750

Re: RV125 - connecting battery

Post by dfa1000 »

Hi Jabcb

Thanks for the reply, i did have a look at the wiring diagram you posted. I was looking at the wiring diagram from the service manual which does look different.

I will have another go at it now.

Cheers,
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: RV125 - connecting battery

Post by jabcb »

Your wiring is likely closer to the wiring diagram in the service manual.

The wiring diagrams for bikes with have-wave rectifiers can be a bit more confusing because some components run on DC & others run on AC. The have-wave rectifiers has a single diode, which is what is shown in the wiring diagram for the 1977 RV125.


To post pics on this forum, you need to post them elsewhere & use an image link here.
Photobucket is a fee & used by many of the forum members for posting images.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
dfa1000
Still in the Driveway
Posts: 4
Joined: Wed Aug 06, 2014 5:57 am
Country: Australia
Suzuki 2-Strokes: RV125, GXSR-750

Re: RV125 - connecting battery

Post by dfa1000 »

Hi Guys

I connected all the wiring up and bought myself a multimeter to test it with. Also put in a new battery and spark plug. The multimeter is reading 6.1v when i connect the multimeter to the tip of the spark plug and the ground to the ground terminal on the battery.

When i try to turn the engine over i am not getting any spark from the spark plug. I have also grounded the spark plug while it is out of the cylinder to test.

Any ideas?

Thanks
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: RV125 - connecting battery

Post by jabcb »

According to the wiring diagram for the 1977 RV125, your bike has a magneto.

Does your bike have a magneto similar to what is in the wiring diagram?
If it does, then the ignition system is a separate system from the rest of the electrical system.
Its is self-powered and does not use the battery for power.

But you got voltage from the battery in the ignition system.
So if you have a magneto, then the bike is wired up incorrectly.

Did you replace the ignition switch?
If so, its likely you used the wrong ignition switch.

What work did you do on the wiring?
Was the wiring modified by the prior owner?
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
dfa1000
Still in the Driveway
Posts: 4
Joined: Wed Aug 06, 2014 5:57 am
Country: Australia
Suzuki 2-Strokes: RV125, GXSR-750

Re: RV125 - connecting battery

Post by dfa1000 »

Yes the bike has a magneto, I didn't change the ignition switch on it. When the key is turned off there is no power going to the spark plug. When the key is turned to the ignition position then it dos get power.

With the wiring i just put it all back together as it was apart when i got the bike. I would say the wiring was not modified at all.

The RV125B diagram looks like it is the closest to my bike. On the diagram it shows a kill switch button but on my bike there isnt one. I tested the ignition coil and was recieving some resistance in it. I wish i had another ignition coil to test it with.

So does the magneto just recharge the battery and make the lights work?
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: RV125 - connecting battery

Post by jabcb »

Take a look at the wiring diagram.

The B/W wire is the ground.
Per the diagram it connects to the ground at one location.
The B/W wire probably grounds to the frame & may actually have more than one ground location.
Check to make sure the B/W has a good ground connection.

The magneto has separate charging coils to power the ignition system & the bike.
The Y/R, Y/W & G/W wires power the bike.
The B/Y wire is for the ignition system & is electrically isolated from the other wires.

The B/Y wire from the magneto goes to the ignition coil & ignition switch.
In the on position, the ignition switch does not connect the B/Y wire to anything.
In the off position, the ignition switch connects the B/Y wire to the B/W wire (the ground wire).

You are getting no voltage at the coil when the bike is off, which is correct.

You are getting voltage at the coil when the bike in switched on.
Is this when you are trying to kickstart the bike?
Is this when you are not trying to kickstart the bike?

Since your bike didn't run, we don't know what the prior owner did.
He may have installed a different ignition switch.

Disconnect the ignition switch.
Make a little chart like the one in the diagram that shows how the switch actually works.
How does it compare to the one in the diagram?

With the ignition switch disconnected, check to see if you get a spark at the spark plug.

Do not try to start the bike with the ignition switch disconnected.
It may start but then you don't have a way to turn the bike off.

Do NOT connect your multimeter when you turn the motor.
You may get a voltage spike that damages the multimeter.

To post images here, you need to upload them to a photo sharing site like photobucket.
(Photobucket is free.)
You then include a image link in you posts here.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Post Reply