Looking for help on 76 XS650

[Mischief]

Looking for a starting point on this bike I am trying to help someone out with.

76 XS650
Completely Stock
Came to me in pieces. Everything back together.

There are going to be numerous issues but I am wanting to start on the basics. I have reviewed and hooked up all wiring following provide diagrams in tech forum.

I am not able to get the starter to engage using the switch. I can use jumpers to starters and I can jump the solinoid getting the starter to engage.

I disconnected the ground wire from the trees and ran a temp from the frame motor mount to the handle bar clamp.

I have gone through left and right housings cleaning up contact areas to ensure ground.

Ignition switch is new.

Single fuse system that has been temp removed and jumpered with a solid wire.

The only thing I get when the start button is pushed is the brake lining switch light comes on. Will that prevent it from starting if the diode is bad.

At a loss on this one. I have spent hours tracing and hours reviewing info on the forum but I am at a loss.

If it were my bike, all would come out and wiring simplified but not an option with this one at this point.

Any thoughts?

 

[Grinder]

I would disconnect the blue/white wire at the soleniod and see if it grounds by pushing the starter button. The blue/white comes from the button so if your not getting a ground, start tracing the wire back towards the button for problems. Your bars are chrome, right? Painted bars can cause problems as you probably know.

 

[Mischief]

Chrome bars

 

[Mischief]

I am getting 11.76 volts (just under what battery reads when direct post to post) to the solenoid and 0.00 when I check ohms so ground is good.

 

[Mischief]

Swapped solenoid with one that I know works so should not be the solenoid.

 

[gggGary]

What happens if you ground the blue white wire from the solenoid? If that cranks it the problem is downstream in the blue white wire or the handlebar switch to ground.
If nothing happens then double check that your red white wire has 12 volts, if it does, then there is something amiss with the solenoid.

 

[Mischief]

What happens if you ground the blue white wire from the solenoid? If that cranks it the problem is downstream in the blue white wire or the handlebar switch to ground.
If nothing happens then double check that your red white wire has 12 volts, if it does, then there is something amiss with the solenoid.

No crank and red wire read 12.09. I agree a problem with the solenoid but worked fine when I pulled it off my 79 xs650. Same solenoid. Just having trouble wrapping the logic around things.

 

[gggGary]

What do you get when you ohm the blue white to the red white? No power, both wires disconnected. Ie checking the coil in the solenoid.
To review; with everything hooked up you can jumper the two big solenoid terminals with a screw driver and it will crank?
My gut feeling is a ground issue, where is the main battery ground wire connected?

 

[Mischief]

What do you get when you ohm the blue white to the red white? No power, both wires disconnected. Ie checking the coil in the solenoid.
To review; with everything hooked up you can jumper the two big solenoid terminals with a screw driver and it will crank?
My gut feeling is a ground issue, where is the main battery ground wire connected?

0.000 ohms at solenoid red/white to blue/white with no power.

Ground from negative terminal of battery to frame rail behind battery. Scuffed and cleaned with emery cloth prior to all other tracing. No doubt we are on the same page just feel like I am chasing my tail.

What would you check next?

 

[retiredgentleman]

You need to replace the 20 amp main fuse. To leave it jumpered with wire can lead to a harness melt down or even a fire.

 

[Mischief]

You need to replace the 20 amp main fuse. To leave it jumpered with wire can lead to a harness melt down or even a fire.

I dig it and have every intention to do so but the fuse is a moot point until I figure out the primary issue of the starter not engaging. No disrespect because I certainly agree with you that it needs to be done.

 

[retiredgentleman]

0.000 ohms at solenoid red/white to blue/white with no power.

Ground from negative terminal of battery to frame rail behind battery. Scuffed and cleaned with emery cloth prior to all other tracing. No doubt we are on the same page just feel like I am chasing my tail.

What would you check next?

The ground needed to operate the starter relay comes directly from the starter pushbutton on the blue/white wire. The bars must be grounded. Use a VOM on ohms X1 to find where you are losing the ground.

 

[retiredgentleman]

I dig it and have every intention to do so but the fuse is a moot point until I figure out the primary issue of the starter not engaging. No disrespect because I certainly agree with you that it needs to be done.

Its a moot point until the harness catches on fire.

 

[Mischief]

The ground needed to operate the starter relay comes directly from the starter pushbutton on the blue/white wire. The bars must be grounded. Use a VOM on ohms X1 to find where you are losing the ground.

I ran a new ground from motor mount to bar clamps. I cleaned bars and mounts to make sure proper contact is made.

 

[Mischief]

Its a moot point until the harness catches on fire.

Again, no disrespect. I appreciate your help and if you feel that strongly that I am potentially going to cause a harness melt down, I will throw an inline fuse to make sure I don't create additional damage prior to any additional testing.

 

[gggGary]

RG offers good advice and I concur.

Again if you short the big terminals on the solenoid, the starter cranks?
IF so jumper the red white to the battery and blue white to a ground.

 

[Mischief]

RG offers good advice and I concur.

Again if you short the big terminals on the solenoid, the starter cranks?
IF so jumper the red white to the battery and blue white to a ground.

Input is greatly appreciated on this end and I don't want to do any more damage to the harness.

Inline fuse installed with 20 fuse.

When I jump solenoid from batter terminals starter cranks strong. Back to searching for bad ground.

 

[Mischief]

Thanks for the help on this. I was able to trace the problem to the safety for the starter. Once I pulled it and tested the leads going into the back the numbers were all over the place. A few good taps on the side and it started to work again. I will get one in and replace it but working well enough to move onto the next step.

No spark.