Possible elec problem?

Greetings all,
I have a '82 750 that I am trying to get on the road. I just used all of your wisdom to refurbish my carbs, THANK YOU very much. Now, my problem is that it will crank over, it starts then when I let off of the start switch it dies. I found that the 3 wires from the generator are brow and not white. The red wire off of the voltage regulator plug is somewhat melted and the main fuse gets very hot when I force it to run holding the start switch. Any thoughts? By the way, the carbs make the bike purrr while it is running

Christopher

 

Starter brushes, find their specs, pull em off and check em. clean em up good if theyre in spec and reinstall them, from what it sounds like is it is drawing too much power causing over heat and low voltage issues.

 

ok, just got done cleaning up the starter as suggested. The brushes do need replacing, but now it just spins. What did I do wrong?

 

I fixed the starter, must not of got it in there correctly. Back to the original problem. The battery is new. I spliced in a modern single fuse block for the main fuse and bypassed all the burnt wiring. It is hard to start, then when it does start, as soon as I let off of the start switch it dies. Just took #4 plug out and grounded it and was not getting any visible spark. I assume that I am not getting spark on the others. Battery voltage was 12.5 Volts.

Christopher

 

Anyone have any ideas on the bike shutting down when I let off of the start button? I took it apart and cleaned it, still no joy.

 

If you are getting a no spark condition, you need to examine your connections at the TCI, the TCI itself (they have a tendency to crack solder joints), the coils (check their resistance), coil voltage (make sure you are getting 12 volts to the coils), and make sure your kill switch is working correctly and isn't inadvertently engaged (it has happened).
Have you swapped out for new spark plugs yet?

 

As you all know, when the bike runs great life is good. When the bike has problems seems like everything is broken all at once and then moves from problem to problem. The cutting out when the start button is released seems to have fixed itself. Now, It starts right up, I use the choke to warm it up trying not to get too carried away with the RPM's. It will run for about 2 minutes then cuts out suddenly, like the kill switch is flipped. I turn the key off, let it set for a few, turn the key and it starts right up. This happens about 3 times in a row then it will run all day. I have checked all of the above but I have not put new plugs in it in a while.

 

This sounds like the Ignition Circuit haas a connection or Relay that is playing "Hit and Miss"

Try unplugging the Safety Relay for some testing.
The Safety Relay is under the Tank just ahead of the Fuel Tank Hold-down Bolt.

With the Safety Relay pulled ... the Bike MUST be in Neutral to Start.
If the Bike runs with the Safety Relay pulled ... the Relay or one of it's Signal Switches is causing the Bike to shut-down.

If that is the case ... you'll have to troubleshoot each of the Safety Features to see that the Switches or their linkages and activating levers are working as they should.

 

I checked the relay, per a post I read earlyer. It works as it should. Years ago I bypassed the sidestand switch due to lack of funds. The clutch safety switch is a part I would like to change out soon, but it works fine for now. I am going out right now to check out the kill switch and bleed my brakes. I'll check back later. By the way, will the oil switch that works the light shut the bike down?

 

Kill switch checks out, I gave it a good cleaning anyway. Now that I think about it, one of the fuel enrichment needle springs was corroded when I cleaned my carbs. It was still usable and did not break when I was looking it over. What does this spring do for us? I just took it out for a spin and it did what I have described on start up. I got it down the road aways, when I downshifted it quit once, then it was fine after that. I do have the clutch safety switch bypassed for troubleshooting for now. I will let it get cold then try to get it started and warm without the choke.

 

The oil switch will not shut down the bike.
Good luck on chasing this one down Craiso.

 

The Springs in the Enrichment Valves both return the Valve closed and apply pressure to the Valve Body to keep it closed.

If you have a well stocked Hardware Store nearby, with a Spring Display Section, you can find a replacement for that and others you might need.

You may have to cut or trim the length of the new one to fit, but it will work as well as the original.

 

Getting it started without the choke produced the same results. This weekend I will be able to get some new plugs, address the enrichment spring and hopefully my local dealership has some starter brushes.

 

Well, I think I got it fixed this time. I replaced the brushes in the starter and replaced the plugs. I still had no spark. Consulted the manual and checked the ignition pick up coils, all was well there. The only thing left is the TCI. I had opened it up sometime back, did some soldering and buttoned it back up. This time I looked it over better and fixed some traces the right way this time. Slapped it back in and the bike fired right up and did not intermittantly shut down 8O . Never give up the ship I was always told.

 

Nice!