What did you do with your XS today?

[CaptChrome]

I just reached a milestone (for me at least) on my most recent ride. I looked down when I was on the ride and had to pull over because I had ridden more miles on Trusty Rusty than all of the other owners combined. And there will certainly be more to follow.

 

[SoulMan]

Nice!

 

[DNAPrototypeX]

Last weekend I continued plugging away at creating my custom wiring harness:

And also made this little abomination:

It's a garage door opener with the button removed and replaced with a wire, and the battery replaced with a 12v to 3v step-down converter. The plan is to wire it into the AUX1 output of the mo.unit, which is controlled by a push button on the right handle bar. Every one of my bikes has had a handlebar mounted garage door button of some kind, but this is the first to get one that will never need its battery replaced...

 

[SoulMan]

Last weekend I continued plugging away at creating my custom wiring harness:

View attachment 39524

And also made this little abomination:

View attachment 39526

It's a garage door opener with the button removed and replaced with a wire, and the battery replaced with a 12v to 3v step-down converter. The plan is to wire it into the AUX1 output of the mo.unit, which is controlled by a push button on the right handle bar. Every one of my bikes has had a handlebar mounted garage door button of some kind, but this is the first to get one that will never need its battery replaced...

This is awesome and a great idea.

 

[CaptChrome]

I was riding on some nice two lane when Trusty Rusty just shut down. I pulled in the clutch and managed to coast the bike off of the road and into the shade of some trees. A bit of head scratching ensued. Pressing the e-start resulted in nothing but quiet, so something electrical was amiss. Kicking the bike showed good compression, but no start. I opened the fuel tank and it was half full as it should have been. I pulled all of the fuses and none looked blown. So I resigned myself that I would have to do some deeper electrical troubleshooting on the side of the road.

I do have a small test light in my tool roll as well as a copy of Trusty Rusty's electrical diagram, so armed with those, I started at the beginning. Testing across the battery looked good, so I moved on to the fuse box and checked for power on both sides of each fuse. Lo and behold, the ignition fuse only had power on one side - I was not expecting that! The fuse looked fine, but it must have some internal contact issue that isn't visible. I had a full set of spare fuses with me, so Trusty Rusty was back in action once I replaced the ignition fuse.

Here is a picture of the problem fuse on the bench after I got home - looks like a good fuse, but it is an open circuit when checked with an ohm meter. This was not some no-name fuse either, it was made in Japan by Pacific Engineering Corporation. Live and learn.

 

[lemonhead]

I was riding on some nice two lane when Trusty Rusty just shut down. I pulled in the clutch and managed to coast the bike off of the road and into the shade of some trees. A bit of head scratching ensued. Pressing the e-start resulted in nothing but quiet, so...

I had the same issue once, but with glass tubes. Ignition fuse looked good and intact until I popped it out and realized the end cap of the fuse was what blew.

 

[ElementalWarrior]

I took mom's special out to Mission BC

 

[SoulMan]

I was riding on some nice two lane when Trusty Rusty just shut down. I pulled in the clutch and managed to coast the bike off of the road and into the shade of some trees. A bit of head scratching ensued. Pressing the e-start resulted in nothing but quiet, so something electrical was amiss. Kicking the bike showed good compression, but no start. I opened the fuel tank and it was half full as it should have been. I pulled all of the fuses and none looked blown. So I resigned myself that I would have to do some deeper electrical troubleshooting on the side of the road.

I do have a small test light in my tool roll as well as a copy of Trusty Rusty's electrical diagram, so armed with those, I started at the beginning. Testing across the battery looked good, so I moved on to the fuse box and checked for power on both sides of each fuse. Lo and behold, the ignition fuse only had power on one side - I was not expecting that! The fuse looked fine, but it must have some internal contact issue that isn't visible. I had a full set of spare fuses with me, so Trusty Rusty was back in action once I replaced the ignition fuse.

Here is a picture of the problem fuse on the bench after I got home - looks like a good fuse, but it is an open circuit when checked with an ohm meter. This was not some no-name fuse either, it was made in Japan by Pacific Engineering Corporation. Live and learn.
View attachment 39569

Luckily you had spares and the tester. Great idea. Now you have me looking for a small inexpensive probe

 

[DNAPrototypeX]

I finally finished the wiring harness, confirmed everything works, all buttons, lights, bells, whistles, etc. It starts if you so much as breathe on the starter button (only on full choke for now since the air box isn't back on yet). I'd bet that it'll start first kick every time once it's fully assembled.

Okay... it's not completely finished, but all I need to do is trim the excess wire for the inputs/outputs of the mo.unit, which can be done with it installed on the bike. No more wrapping or heat shrinking, or fighting with deutsch connectors!

I only have a few things left to do before the build is finished:

1. Build the seat base, add foam, upholster cover
2. Install new tubes and tires (waiting on parts order from my local yamaha dealer), balance wheels
3. paint (which I will have done professionally)
4. Add extra water-proofing for the mo.unit (just in case)

 

[CaptChrome]

I had a long, hot ride and when I got off of the bike I saw oil all over the right side of the bike.

I verified it is motor oil not the gear oil I use on the chain and also it does not have any fuel smell to it. Anyway, I will be pulling the tank off and running the bike on the nurse tank to find where the source is. I am kind of expecting the tach drive seal has failed based on where the oil ended up on the bike. Who knows, but I have been surprised before.

 

[CaptChrome]

I found the oil leak (I think.)

I degreased the engine and then started and got the engine hot. Next the tank was removed and the nurse tank was connected. The tach drive cable from the engine was also removed. After restarting the engine, I revved the bike to between 5-7k rpm and started looking for oil. To my surprise, the tach drive was bone dry after several minutes. So, I started looking elsewhere and noticed the following:

A leak from the rocker shaft cap on the intake side of the cam cover. The cap was not that tight, so I took it off, cleaned it up and reassembled the o-ring, copper washer and plug cap. I check torque on certain fasteners each spring, but I had never put a wrench on this cap. it is now added to the list. Hopefully this is the only cause of the leak. The bright side of things is that the oil on Trusty Rusty's frame will slow down any further rust - for a while.

 

[Revvy Kevvy]

I found the oil leak (I think.)

I degreased the engine and then started and got the engine hot. Next the tank was removed and the nurse tank was connected. The tach drive cable from the engine was also removed. After restarting the engine, I revved the bike to between 5-7k rpm and started looking for oil. To my surprise, the tach drive was bone dry after several minutes. So, I started looking elsewhere and noticed the following:

View attachment 39604

A leak from the rocker shaft cap on the intake side of the cam cover. The cap was not that tight, so I took it off, cleaned it up and reassembled the o-ring, copper washer and plug cap. I check torque on certain fasteners each spring, but I had never put a wrench on this cap. it is now added to the list. Hopefully this is the only cause of the leak. The bright side of things is that the oil on Trusty Rusty's frame will slow down any further rust - for a while.

Just added this bolt to my list of bolts to check before I actually get mine out on the road.

 

[Revvy Kevvy]

Bought a Dwell meter to set the new points that are sitting at home waiting for me to install when I finish this business trip. New points, a new ignition coil and some turn lenses.
Its getting really close,

 

[DNAPrototypeX]

Today I found out that my TCI has died (surprise, surprise ). Specifically, the left cylinder has no spark (right has strong spark). I made absolutely sure before ordering parts:
1. Swapped the spark plugs, still spark no spark on the left.
2. Swapped plug wires, still no spark on the left.
3. Swapped coils, still no spark on the left. Also checked coil resistances, all within spec.
4. Switched the wires from the pickups around (left trigger going to the wire for the right on the tci and vice versa), still no spark on the left, good spark on the right.
5. Checked continuity on the wires from the pickups to the tci and from the tci to the coils, all good. (Already knew they were fine as I fully rewired thd bike from scratch, but checked anyway)

I concluded that whatever internal circuit of the TCI controlling the spark for the left cylinder on the left side has a bad component.

I had 4 options:

1. Buy a replacement TCI box used, which may or may not work and will likely go bad soon enough too.
2. Buy a points system on ebay and revert the bike back to the ol' reliable mechanical advance/condensor setup.
3. Give up and cry
4. 2. But also try out an aftermarket electronic ignition system.

Obviously 3. Isn't an option, I've put far too many hours and way too much love into this bike at this point, and I want to have it absolutely dialed for next summer when I go on a continental tour of North America on it.

Option 1 doesn't seem like a good idea either. It means no modifications to my wiring, but I'm not scared of my soldering iron and a little heat shrink. The downsides of having a ticking time bomb on the bike is not very appealing.

I decided, what's another few hundred bucks, and bought a used mechanical advance and points system on ebay, as well as a Tytronic elecronic ignition. I hope I'm lucky and the tytronic unit works well and reliably, but I'll have the points as backup just in case (and I'll be bringing it with me on the trip lol).

Originally, reverting to mechanical advance and using an aftermarket electronic ignition system was the plan, as that's what BJ did on his xs400 build (brickhousebuilds on YouTube), which is one of my main inspirations for my build. But when i saw that most of the systems were out of stock anyway, I just committed to the stock TCI. Why fix what's not broken, right? Cause it's a circuit board from the 80s bruh, that shit's gonna die.

Anyways, wish me luck. Clearly I'm gonna need it.

 

[RadlagerMike]

I had a long, hot ride and when I got off of the bike I saw oil all over the right side of the bike.
View attachment 39602
View attachment 39603

I verified it is motor oil not the gear oil I use on the chain and also it does not have any fuel smell to it. Anyway, I will be pulling the tank off and running the bike on the nurse tank to find where the source is. I am kind of expecting the tach drive seal has failed based on where the oil ended up on the bike. Who knows, but I have been surprised before.

I had a long, hot ride and when I got off of the bike I saw oil all over the right side of the bike.
View attachment 39602
View attachment 39603

I verified it is motor oil not the gear oil I use on the chain and also it does not have any fuel smell to it. Anyway, I will be pulling the tank off and running the bike on the nurse tank to find where the source is. I am kind of expecting the tach drive seal has failed based on where the oil ended up on the bike. Who knows, but I have been surprised before.

 

[RadlagerMike]

How about the Engine Holder on the back side, i dont think it is sitting well without that screw !

 

[RadlagerMike]

with this holder on the right side

 

[CaptChrome]

How about the Engine Holder on the back side, i dont think it is sitting well without that screw !

Ooops! Just kidding.

With the 1981 XS400H/SH and 1982 XS400SJ, Yamaha changed the engine mounts from rigid to elastic. So both the front and rear mounts changed and the mounting point you see without proper hardware was no longer used.

 

[CaptChrome]

Why fix what's not broken, right? Cause it's a circuit board from the 80s bruh, that shit's gonna die.

Counterpoint -
Because that board is from the '80s means that it can be rebuilt pretty easily, just like the rest of the bike. The components are all through board soldered, so no microscope is needed to work on them. The most difficult part of fixing it is removing the conformal coating sprayed over the board to prevent corrosion.

I am willing to put this hypothesis to the test also. I bought the cheapest used TCI off of eBay. It works just fine (it is on my bike now) as does my original. I plan to replace the capacitors and maybe the coil firing transistors on one of the TCIs this winter as a project, and then put it on the bike and run it hard to see what happens. If you are going to dump your TCI, I would be willing to buy it from you and try my experiment on it, since it is already toast.

Anyway, good luck on getting the bike retrofitted. Having a running bike is way better than having a paperweight!

 

[DNAPrototypeX]

Counterpoint -
Because that board is from the '80s means that it can be rebuilt pretty easily, just like the rest of the bike. The components are all through board soldered, so no microscope is needed to work on them. The most difficult part of fixing it is removing the conformal coating sprayed over the board to prevent corrosion.

I am willing to put this hypothesis to the test also. I bought the cheapest used TCI off of eBay. It works just fine (it is on my bike now) as does my original. I plan to replace the capacitors and maybe the coil firing transistors on one of the TCIs this winter as a project, and then put it on the bike and run it hard to see what happens. If you are going to dump your TCI, I would be willing to buy it from you and try my experiment on it, since it is already toast.

Anyway, good luck on getting the bike retrofitted. Having a running bike is way better than having a paperweight!

You inspired me to give the tci box one last chance, and I'm glad you did. I checked all my wiring, but not the wiring going from the connector to the box itself. Turns out that was the issue... I guess I'll cancel my ebay orders from last night lol. Luckily noone ships on the weekend so it shouldn't be an issue.

Live and learn I guess. I've got to be more patient with this thing, be methodical, and thorough before whipping out the credit card. I rewired the whole bike from scratch, but didn't bother verifying the factory wires I did leave were good. Stupid mistake.