78XS rehab

[Eab]

Since your located in a high humidity area, I highly reccomend you also remove and take apart the the Run/Stop switch and soak the whole switch in a cup of Evapo-Rust for afew hours. remove and wash off switch assembly with water, blow dry and re-install. The run/stop switch COMPLETES the running circuit, and if contacts are cruddy the electrickery will not get to coils in order to fire the cylinders. The wires plug-in for that switch is under fuel tank on top right frame rail.

Should've thought of that, the run/stop had been jammed and feels a little loose. That's next up!

[Eab]

Well, here we are. The kill switch, which looked mint from the inside of the housing, was rusted at the contacts And has a cracked housing. Anybody know if it's possible to get just the toggle switch, vs the whole assembly? Probably out of luck. I could try to patch it with epoxy or similar but it's not hardware I want to fool around with.

[DiverRay]

order a right hand switch assembly for any lat '70's Yamaha. You now have all the new parts you need! Wire ends and length are the difference between models.

[Eab]

Got the new switch And new solenoid en route - despite a cleaning it's not holding up its end, and I'm picking my battles.

Learned three things last night!

1) the cutoff switch was engaged even when reading "off", starving the starter of powe
2) it's not a great idea to put trans fluid in the cylinders immediately before trying a "hrm maybe it'll turn over now" test (sans plugs)
3) trans fluid smells like the devil's own urine

[Eab]

Got the front brakes disassembled. The cylinder necks (that engage with the rubber) are badly corroded. Anyone know if that's problematic? It's only the tapered portion, hoping i can grind off the rust and put it back into service. And I'm not gonna toss the brake pads!

[jetmechmarty]

Annual or biannual brake fluid change does wonders.

[Eab]

Looking possibly at replacement brakes. Thought I could wire wheel and sand off the rough patches on the piston, but it Does Not want to get back inside that sleeve. I'm not sure it'd make for a good seal anyway, looking at it.

[Bax]

Can get kits with replacement stainless pistons from Brake Crafters

https://www.brakecrafters.com/collec...s1100-e-f-g-h/

[Eab]

Can get kits with replacement stainless pistons from Brake Crafters

https://www.brakecrafters.com/collec...s1100-e-f-g-h/

Good call! Got them coming with the rebuild kits. There are a few aspects of this rehab I don't want to mess around with.

I wonder, do folks doing a rehab like this generally pull all the wiring out and redo with fresh wires as a matter of course? I've cleaned up the ground connections and all, but if broken wiring inside the sheathing is a pretty standard problem, I'll bite the bullet. Got to track down a usable fuse panel anyway, so I'll be fiddling with the electrical in any case.

[DiverRay]

That looks like my first attempt to replace the fuse box. As long as none of the wires are rubbing against the sharp edges of the sheet metal, you should be OK.
The main problem areas with the old wires are the connections. Clean or replace connectors that are dark colored, and replace any that look like the plastic has gotten hot. Tony has the replacement parts here: http://www.oregonmotorcycleparts.com/ he is a member of this board, and has been for quite a while.
Her is a link to the electrical on this site: https://xs11.club/forum/repairs/battery-electrical-aa This has all the info you will need to decide how far you need to go with the wires.

[Bax]

Probably no need for complete wiring overhaul but a few problem areas are known: 1.fuse box and you seem to know this, 2. wires in loop backs to the timing advance pickups, 3. Key switch plug/receiver connector in the headlight bucket has a pin set that heats up if resistance due to corrosion that will take out your charging system, usually indicated by a brown stain on the connector housing. Geezer (Tony) has the connectors and regulator at http://www.oregonmotorcycleparts.com/ The fuse box upgrade kit is being handled by Len at XJ 4 Ever. http://xj4ever.com/catalog/d-3-fuseboxes.html These kits are well done and clean up the fuse box mess well. Lots of posts on the timing advance wires.

Bax

[jetmechmarty]

Probably no need for complete wiring overhaul but a few problem areas are known: 1.fuse box and you seem to know this, 2. wires in loop backs to the timing advance pickups, 3. Key switch plug/receiver connector in the headlight bucket has a pin set that heats up if resistance due to corrosion that will take out your charging system, usually indicated by a brown stain on the connector housing. Geezer (Tony) has the connectors and regulator at http://www.oregonmotorcycleparts.com/ The fuse box upgrade kit is being handled by Len at XJ 4 Ever. http://xj4ever.com/catalog/d-3-fuseboxes.html These kits are well done and clean up the fuse box mess well. Lots of posts on the timing advance wires.

Bax

Generally, most of the wiring is disturbed very little and it's up under the tank and seat. IMHO, if there aren't cracks in the insulation, just leave it alone. Thoroughly clean all the connectors. I like Deoxit to protect them. The kit from XJ4Ever is a very good move. Also, behind the fuse box is the alternator connector. That is the most likely connection to fail. Clean it well. You can unclamp the pickup coil wires and alleviate some of the extreme movement.

[Eab]

Got the new solenoid and right hand control unit in! Only issue is, the wiring. I'd hoped control's connection to the xs would be standard, unplug the old and plug in the new, but it's looking more complicated.

The connection points dont match, and neither do the wire colors. I've got the Haynes manual which'll show what the wiring on the moto does, but the replacement unit (K&S) didn't come with one, and there's not one on the website. Also, the harness for the K&S unit has 6 wires, while the OEM has 5 - I suspect that's an extra ground? Anyway, is the only path forward to take apart the old switch and try to match colors to functions? Or has anyone jumped through this hoop before?

[Bax]

Eab, Pics and part numbers. That would help us help you.............

Bax

[Eab]

Eab, Pics and part numbers. That would help us help you.............

Bax

Ah that makes sense, sorry. I've addressed the control unit issue at least, did it the hard way, but now I'm on to what I suspect is the Big Problem: exhaust. I've got significant rust on one of the silencers, but from what I've read here replacements for this particular thing are Very hard to come by.

I'm trying to figure ways to address this. I don't know how to weld, and don't have the kit for it, but if I have to pay someone to do a little work that's OK. I'm mourning the chrome pipes look a bit, but other parts of the exhaust are pretty rusted (not as bad as this!) elsewhere.

I want to get it up on my bench to look it over, but I can't see how (once it's disconnected) to do so. It's the stock unit, with the small boxes built into each where they connect in the middle. My Haynes doesn't cover the removal procedure. Under normal circumstances, I'd fiddle around in some hopefully nondestructive way but with the exhaust being as irreplaceable as it is, I'm breaking out the kit gloves.

Anyone know how to get the exhaust off this thing? I'm guessing it involves disconnecting the two halves (right and left) but I don't want to bet my pipes on it.