1981 XJ650 Shut off while riding won't start. Please help

Hey guys.

I have a 1981 Yamaha XJ650.
I thoroughly rebuilt the bike over last winter. (carbs, fusebox, forks...)
Needless to say the bike has been running like a champ all summer.

Took it out today, and now it's dead.
I started it this morning, let it warm up. As I started to ride it bucked twice and then died in my drive way. When attempting to start it nothing happened.
No clicking, nothing. I thought great! As I was about to push it back into the garage I tried the starter button one more time. It cranked, and after a couple seconds it started. So off I went to get gas, and for a bit of a spin.

The bike ran great for about an hour and a half. Not a hick-up.
Then on the way home, steady throttle it just cut out, (as if i flipped the kill switch). I pulled over to the side of the road. Same as in the morning no reaction when pressing the start button. Ignition on, in neural (light on), no clicking, nothing.

I got a tow home, and started checking everything.
The fuses look good. I searched the forum, and some symptoms point to the Starting/Ignition Cut-Off/Neutral Safety relay. Located it under the gas tank (metal 4 point relay correct? ) Disconnected it (to bypass it) still nothing. Nothing happens when i push the start button.

I don't believe I have a sidestand switch/relay since the bike is a 1981., as that could also be a culprit.

Can the TCI be defective?

I'm kind of out of ideas.
I'm good with mechanical repair, not so much electrical.

Any ideas to zero in on the problem?
Any help appreciated.

Thanks

 

COuld be lots of things: kill switch and key switch are two of them, relatively easy to check. COuld also be the side stand switch. COuld also be your main fuse, even if it looks good, it can be sort of loose.

 

Just an update

Jumping the starter solenoid turns over the starter but the engine does not start. I'm guessing no spark because of some other fault in the ignition circuit.

Also the main 20A fuse is fine. Pulling it cuts all power.

 

You may not have a sidestand relay but you DO have a sidestand SWITCH. Which could be the cause of your problem.

 

Than's for the replies gents.

bigfitz52, all the info I'm finding is that the 81 XJ650 Maxim does not have a sidestand switch.

I'll check when I get home just to be sure.

 

Re: 1981 XJ650 Shut off while riding won't start. Please hel

Ok, another update...

I checked for a sidestand switch and I definitely don't have one.

Second I did all of the following tests. *****denotes results
From this thread:
http://xjbikes.com/Forums/viewtopic/t=1 ... =next.html


Start with the bike on the center stand with side stand up and the transmission in neutral. You will also want the ignition switch turned to on and the kill switch turned to on. The numbers in the picture coincide with the steps listed below.

*****Check!


1. Test the voltage at the battery. It should read at least 12.5 volts. Charge and retest as needed.

******Check (just around 12V)


2. Using an old screwdriver, short across the two large terminals at the starter solenoid. This will bypass the solenoid and allow the starter to crank the engine. If the starter doesn't crank, perform a continuity test between the negative battery terminal and the engine case. If you read no resistance (or almost no resistance), repair or replace the starter. Otherwise, repair or replace the ground cables and retest.

******Starter cranks


3. Locate the pigtail from the starter solenoid and unplug it. Using a jumper lead, hook the Red/White wire from the solenoid to the battery's positive terminal. Using another jumper lead, hook one end to the solenoid's Blue/White wire. Momentarily touch the other end of this lead to the battery's negative terminal. If the solenoid is functioning properly, the solenoid should click and the starter should begin cranking the engine. Repeat this step several times to ensure the integrity of the solenoid. If nothing happens, repair or replace the starter solenoid.

*****Starter cranks



4. If the solenoid checks out, hook your continuity tester between the battery's ground terminal and the Blue/White wire coming from the bike's wiring harness for the starter solenoid (solenoid pigtail unplugged). It should read an open state while the starter button is not pressed. When you push in the starter button, the tester should then read a closed state. If there's no change, inspect, clean, or replace the starter button switch and its ground and retest.

******Reads closed state as described when the starter button is pressed

5. Using your voltmeter, hook its ground wire to the battery's negative terminal and its positive wire to the Red/White wire coming from the bike's wiring harness for the starter solenoid (solenoid pigtail unplugged). The meter should read 12 volts (approx.) if the bike is in neutral, and/or the clutch lever is squeezed and side stand is up with the key on and the kill switch on. If not, inspect the wire coming from the starter circuit cut-off relay for any breaks or chaffing. If the wire looks good, go to the next step.

*****This is when things go a bit wrong. Connecting everything as described only shows 0.5V!! I checked and the wire from the cut-off relay has continuity with the solenoid pigtail wire.



6. Remove the left-hand side cover to gain access to the starter circuit cut-off relay (NOTE: your relay's location may be located elsewhere such as under the fuel tank). Using your voltmeter, hook its ground wire to the battery's negative terminal and its positive wire to the Red/White wire coming from the kill switch (starter circuit cut-off relay pigtail unplugged). The meter should read 12 volts (approx.) if the ignition switch is on and the kill switch is on. If not, you will need to inspect, clean or replace the 20A Main fuse, the ignition switch, the kill switch, or the wiring between them. If you measure 12 volts (approx.), go to the next step.

*****Once again connecting everything as described only shows 0.5V!! When I flick the kill-switch the voltage drops to 0. The main 20A fuse is fine.


7. Hook your continuity tester between the battery's ground terminal and the Sky Blue wire coming from the bike's wiring harness for the starter circuit cut-off relay (relay pigtail unplugged). It should read an open state while the transmission is in gear. When you shift into neutral, the tester should then read a closed state. If there's no change, inspect, clean, or replace the neutral switch and its ground and retest. If it checks out, proceed to the next step.

*****Another weird reading. It's exactly opposite to what's described.
In Gear it reads a closed state, and in Neutral it reads an open state.

8. Hook your continuity tester between the battery's ground terminal and the Black/Yellow wire coming from the bike's wiring harness for the starter circuit cut-off relay (relay pigtail unplugged). It should read an open state while the clutch lever is released and/or the side stand is down. When you squeeze the clutch lever and the side stand is up, the tester should then read a closed state. If there's no change, inspect, clean, or replace the clutch and side stand switches and their grounds and retest. If they check out, proceed to the next step. (Note: some models may not have a side stand switch.)

****Working as described.


So based on this it looks like there is a problem with #5, 6 and 7.

Any ideas what could be causing the 0.5V, and the reversed neutral switch behavior? Like I said the bike ran perfect before.

Thanks

 

Digit.......can't help you with the problem, but can sympathize............I had a similar incident three summers ago. Was out on on of my bikes, it was running fine. Went around a curve on a windy twisty road (Ilion Gorge for those who know it) and was about half way through, heading south. Bike quit like the kill switch was hit. NOTHING would start the bike, had horn and lights..........that was it. I turned around and rolled quietly for a mile to a co-worker's house and we trucked it home (half an hour drive away).......pushed it up across the lawn to the house and tried it a few times......nothing. Mad as a hornet, I decided to grab a lunch. After lunch I went back out, tried it..........nothing. So, I put the seat back on, sat down to 'think'. When I sat down, I heard small click like a relay.....hmmmmm------decided to try it again, and it fired right up. Now, I haven't figured it out YET.........it's been fine ever since. I don't know if there's a 'tilt'relay that could have been triggered==I wasn't leaning that far, and it should have corrected itself when I was rolling down the road on the shoulder.............etc...................

All I can figure is that one of the relays got jarred and tripped. so, try tapping on all the relays under the tank. Use the back end of a screw driver to tap them a bit.

Hope you find it!

 

See results from #6: "When I flick the kill-switch the voltage drops to 0."

Sounds to me like a good possibility that the kill switch contacts and/or wiring need attention.

Another troubleshooting trick: simply unplug the safety relay. This will bypass the safety circuits and if the bike starts, at least you know that you're on the right track. If not, you'll know the problem lies elsewhere (like the kill switch.)