Glad to be here and the XS that was meant to be...

[AmbientMoto]

Yep. First one I ever broke was the oil pan drain hole on an old Honda; had to take the pan to a machine shop. Ironically, the guy put a non-metric thread in. It just didn’t seem right having a metric bike with a SAE oil drain…

New fitting ordered; onward!

 

[AmbientMoto]

Petcock rebuilt; new fuel barb installed and no leaks
Functions *mostly* correctly... the "Reserve" setting works correctly under vacuum but allows a slight fuel drain when no vacuum is present. More than a drip; a slow small stream. I think we installed the various rubber bits correctly, but we'll have to open it up again.


Also opened up the rear tailight assembly; the OEM bulbs both had partial functionality with a few of the individual mini-bulbs still lighting. They will be replaced with LED's.

Look at this old bulb!

 

[CaptChrome]

That doesn't look like an OEM bulb, but a first gen LED that has seen some better days. I agree that it is time for an upgrade! Also, rather than fight with my old vacuum petcock, I just bit the bullet and bought one of the manual ones that fit the tank. If you continue to have trouble with yours, it is something to think about.

 

[AmbientMoto]

Ok that makes more sense.. looking at the bulb closely... interesting.

We have a spare/backup petcock. It works but to access all of the gas in the tank the tubes will need to be cut/shortened. I've always replaced petcocks with non-vacuum versions or bypassed the vacuum function BUT I'm curious if we can get the original to work correctly. It certainly feels like a more solid piece of hardware.

 

[AmbientMoto]

Finally figured out a brake cable solution. 1981 Special with drum brakes front and rear.

I ordered a Venhill Universal Kit. It didn't work. This was kit U01-4-101-BK. I sent it back. The inner cable was small; didn't make me confident about it's suitability as a brake cable. Parts weren't the right bits either.

Ordered a second Venhill Universal Kit. U01-1-1-100-BK. It came with all of the correct bits, an adjuster that was the proper spec, and the inner cable was nice and robust.

I cut the new housing a bit shorter than the OEM as the bars we are using require less cable length. I re-used the rubber boot but otherwise I used all new hardware from the Venhill kit. Incidentally, the adjuster is longer by about 8mm and the inside opening is smaller, giving the impression that the walls of the adjuster are a bit thicker. The old adjuster, thought it may be 40 years old, is most likely made of better metal.

Adjusted the brake actuators a bit so both shoes were working together as they should.

Soldered the new cable end; it's basically identical to the OEM cable end.

Cable works great; nice and smooth even before lubricating, even better after.

Here's a pic of the new cable. I'd highly recommend the Venhill kit after using this one.

 

[CaptChrome]

Thanks for the info on the kit. I did check out the custom cable shop at motionpro.com, and they will make one up and ship it to you (cost looks to be in the neighborhood of 80-100 USD - so pretty expensive.) I do plan on visiting the shop that makes cables for the custom builders in my area and find out their cost and capabilities also as I would like to support the local guys if possible.

 

[Buddha]

Hey Ambient
Looking at your cable pic, I have to ask, is that regular plumbers solder you used?

Read the chats on the linked page below, especially the bottom post which has great info.

http://classicmotorcycleforum.com/index.php?topic=4224.0

 

[AmbientMoto]

Thanks for the heads up. I just used my usual solder... but I'm re-thinking that now. Wouldn't be too difficult to re-do that end.

I'm looking at a few things on the SRA Soldering Website.

 

[Buddha]

That's good to hear. Myself, I would use silver solder, even then I would build 2 and destruct one to prove the cable would fail before the solder joint. I did that on airplane cables when I was building my airplane, that used swedged cable ends. Made me sleep better at night lol.

 

[AmbientMoto]

@Buddha Any suggestions as to brand or a specific solder/flux to look for? The cable is steel, the connector is brass.

 

[Buddha]

https://www.trackofthewolf.com/Categories/PartDetail.aspx/1023/1/SOLDER-SB

Use ~300W soldering iron, no torch

 

[Buddha]

The most important thing is to fray the cable into a "rose" at the end of the fitting and solder it. This prevents the cable from being pulled through the fitting.
Lots of info on the web about making cables.

 

[AmbientMoto]

Ok awesome; thanks. There was a time when I spent a good amount of time in the woods with a muzzy; it was fun to see that site again.

 

[AmbientMoto]

Looks like that solder is a (quality) 94/6 tin/silver blend with appropriate flux. So that's what I should look for? I can probably find some locally.

 

[Buddha]

 

[AmbientMoto]

Today was a monumental day... First test ride! Not registered yet and no lights so we stayed in the neighborhood. I took it around once then my daughter jumped on as pillion (this is the bike we've been building for a home-school project).

The good:
Bike runs well and shifts well. The engine pulls great! Brakes work surprisingly well. No leaks from the fuel system Suspension... a bit soft but ok.

The bad:
We have a small oil leak around the neutral / oil sensors. Ugh.
While the idle is smooth and sounds fantastic, when the throttle is blipped, it hangs. And doesn't really want to come down. The throttle cable is new and snaps back as expected. So for example, coming to a stop sign, the engine just stays at 2000-3000. I also had one backfire when I pulled into the garage, so perhaps we have a lean condition.

When the idle is hanging, I can reach down and slightly adjust the idle screw (not the fuel mix) and that makes it come back down. So the carbs may just need a more robust cleaning.

More to sort, but what a fun day

 

[Buddha]

Nice! There's always some snags to work out, good job, your daughter must be proud.

 

[CaptChrome]

That bike sounds pretty sweet going down the road! Get those little issues sorted out, and it will be a really nice ride! Great work you two.

 

[JPaganel]

While the idle is smooth and sounds fantastic, when the throttle is blipped, it hangs. And doesn't really want to come down. The throttle cable is new and snaps back as expected. So for example, coming to a stop sign, the engine just stays at 2000-3000. I also had one backfire when I pulled into the garage, so perhaps we have a lean condition.

When the idle is hanging, I can reach down and slightly adjust the idle screw (not the fuel mix) and that makes it come back down. So the carbs may just need a more robust cleaning.

There are three things that will cause that.

1. Vacuum slides.

With carb tops removed they should drop in with a satisfying clunk. The diaphragms should be pliable and with no holes.

2. Synchronization.

You did synch them, right? I haven't seen that in the thread.

3. Leaky throttle shaft seals

These are actual lipped seals, not o-rings like some people think. They harden and start leaking. They are still available from Yamaha, but I don't think they are listed as separate parts for the XS. Part number 256-14997-00-00

Replacing them requires breaking the carb rack and removing throttle plates (butterflies). It is not hard, but it is absolutely imperative you have a JIS screwdriver for it. The screws are tiny, the ends are peened over. Use a regular Philips, and you are about guaranteed to strip them and have to drill them out. They are 3mm, at an angle, inside the carb bore. It will be a pain.

 

[AmbientMoto]

@JPaganel Thanks for that list. We did NOT in fact sync; I meant to do it after the test run since the engine was nice and warm... but had to cut the session short. Hopefully that's the culprit. If not, we'll check the other suspects.

Yes, I have an assortment of JIS drivers. Definitely a must for Japanese bikes!

Also, thanks for the part number. Might be a good time to rebuild the carbs anyway.