no juice

[canine]

hope someone can give me a little insite with this. I own a 79 xs750, started it today and had it running for a couple of minutes turned it of and when i went to restart it there was a single popping noice and the lights on the instrument cluster went out(nutrual and oil indicators). checked the battery and fuses and they seem to be alright. this was the first time ive had it running since storing it for the winter

[ratbyk]

No Power

Start checking electrical connections. Particularly ones related to the battery.
Battery cable connections, Ground strap where it grounds to the frame. Positive at the starter solenoid. Actually remove each one, clean(scrape,wire brush). Smear with dielectric grease and then locate the large red wire that provides power to the fuse box, ignition switch.
Happy hunting.
Ken/Sooke

[TopCatGr58]

Hey Canine,

That single loud pop sounds like either a wire shorted, or then a FUSE blew, most likely the main fuse, like Ratbyk said, look for the large red wire that comes off of the starter cable that eventually will run to the fuse block! Fuses can blow when they get old, but usually it's because a wire has worn bare and has inadvertently grounded against the frame/body somewhere, like in the headlight bucket, but could be anywhere the wires are near moving parts, ie. steering head area, but also under seat, tank, etc!.

IF the connectors have developed much corrosion, they can add considerable amount of resistance to a wire, which can cause it to overheat, etc.! Good luck with the hunt!
T.C.

[canine]

Thanks for the input guys, will start trouble shooting this weekend. The popping noise sounded like it came from under the tank or the head light assembly(put a fairing on last summer with any luck that is where the problem is.)

oh ya one more thing, is there a main fuse on these bikes? all i have under the seat is 4 fuses in the fuse box. I know my 83 wing has main fuse by the starter selonoid. I looked and looked and cant find one on the 750.

[jayklink]

Triples Forum

Try the Triples Forum.
http://www.yamaha-triples.org/
Guys there will be able to help you also.

**fixed link**T.C.

[ratbyk]

Short Blowing Fuses

If you have just mounted a fairing and are now blowing fuses it is a very good indicator that you have pinched a wire with the fairing mounts or something is wrong in the wiring contained within the fairing.
Check around the fairing mounts for a pinched wire. If nothing there is evident then disconnect the main connector to the loom to the fairing and see if your fuse blowing stops.
There will definitely be a main fuse on your XS750. Where, don't know. Never owned one. If you are going to keep the bike suggest you buy a shop manual for it.
Ken/Sooke

[TopCatGr58]

I just reviewed the wiring diagram for the D-E series, and since yours in a 79, I would think Yamaha made them similar to the XS11s. It shows only 4 fuses, just like the XS11, the main fuse is one of those 4 in the fuse block. Later, they added a separate main fuse mounted on the other side of the bike on the XS11.
T.C.

[canine]

well unfortunately i havent had the chance to start troubleshooting,hopefully next weekend. Damn this sucks,we're having beautiful weather here in wisconsin.