81 XS400H – putting the Trusty back into Rusty

Thanks @Buddha for the suggestion. I have heard those work well, but do not have one of those carving knives. I have used a serrated bread knife in the past, and that works well, but I am now forbidden from using kitchen equipment for my projects. I think that happened after I used a butter knife to pop out the tail lights on a VW New Beetle (perfect tool for that, BTW). I am also strictly prevented from using the oven for curing paint coatings or for the heating of castings to make bearing installation easier. The conditions I must work under are pretty grim.
Side cover repair-
First off, a small hole was drilled at the very end of the crack. This is to help dissipate stress forces which tend to concentrate at the sharp point of a crack. If my repair fails, at least the crack should not progress further.
Side Cover Repair1.JPG

Next, the paint was sanded off around the crack in order to expose the raw material of the side cover. It looks to me like polystyrene plastic (the stuff plastic hobby models are made of). Even though I am not showing it, I did the same on the inside of the cover as well. I plan on reinforcing the crack with some fiberglass cloth, so I cut some small patch pieces and also pulled some glass fibers out in order to stuff in the hole I drilled.
Side Cover Repair3.JPG

I think there are three glues that might work for this repair – plastic hobby model cement or all-purpose plumbing pipe glue that can be used for ABS pipe, polyester fiberglass resin, and epoxy resin. The first two work by softening the styrene in the cover and chemically “weld” to the parts. The epoxy resin relies on mechanically attaching itself to the part. At the moment I have some all-purpose pipe glue, so that is what I am going with. I put glue in the crack and over the exposed plastic, placed the fiberglass cloth patch in the wet cement and then completed wet out of the cloth with a bit more cement where needed.
Side Cover Repair4.JPG

Some glass stands and glue were jambed into the hole and then the patch placement was repeated on the inside. However, I used two fiberglass patches for added strength on the inside where the extra bulk won’t be noticed.
I put some polyester body filler on the side cover repair.
Side Cover Repair5.JPG

The cover is now sanded and ready for some warmer weather so that I can paint it. Once Trusty Rusty leaves the shed, it will spend its life outside, so something will be needed to keep the rain, snow, debris and UV rays off of it. I have some leftover marine canvas so I took some measurements for a fitted cover, templated up some panels and cut them out of the fabric...

And I have started on stitching all of the pieces together.

This work needs to be done with bare hands and with the temperatures out in the shed, I am having to take lots of breaks to warm up. I figure I still have an hour or two of work out there in order to finish it off.
Side cover repair-

I think there are three glues that might work for this repair – plastic hobby model cement or all-purpose plumbing pipe glue that can be used for ABS pipe, polyester fiberglass resin, and epoxy resin. The first two work by softening the styrene in the cover and chemically “weld” to the parts. The epoxy resin relies on mechanically attaching itself to the part.

"ABS plumbing glue" is really just some ABS in a solvent. It works well on motorcycle plastic, and can make good repairs with fiberglass.

I am not sure what the all-purpose plumbing glue is, but there really shouldn't be any issue with it either. Motorcycle plastics are ABS, just like drainpipes. Only pipe ABS is dyed black.

My preference is ABS glue over pretty much all the other stuff. I've filled cracks and even built up missing pieces out of it.
I haven't gotten much done this week other than finishing the bike cover.

The weather warmed for a day and I also managed to get some primer on the side cover repair and am looking for the next window to do the top coats. Just chipping away at it. I do have a pretty busy schedule the next few weeks, so I will see if I can do some small bits to get them off of the list.
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It has seemed that when I have some time to work on Trusty Rusty it has been too damn cold, but lately it has started to look like spring may actually be on the way.

I got the tank badges on and determined that however the finish looks at the present time is good enough for me. Paint work is officially done.
Tank paint4.JPG

Progress on the seat, the last major job before spring commissioning, has resumed. The tools used are a hacksaw blade for straight cuts, a surform file (essentially a cheese grater) for finish work and what I call a foam grinder that I made up. The grinder is a sanding pad with staples driven in. So far it has done a hell of a job destroying seat foam and is almost not controllable. I have not given up hope yet and will remove half of the staples to see if I can get this thing to work for me. The good thing with foam is that if you screw it up, you just have to glue some more on and start again.
Seat foam5.JPG

At any rate, I did get the basic shape of the seat knocked out and the foam sides glued on. I have a lot of foam shaping to do though, and hope the foam grinder will work out otherwise I will be logging some long hours with the cheese grater (which will require I add a case of beer to the project budget - not ideal).
Seat foam9.JPG
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Pulling half of the staples and improving my technique made the foam grinder work. At least it allowed me to round off the foam blank without the risk of the tool grabbing the whole seat and throwing it across the shed as happened several time before. So I was able to work things down to a more refined shape.
Seat foam10.JPG

That got refined further and then subjected to repeated "butt tests" on the bike as things progressed. Having reached what I see as the final shape, I used some glue and foam "sawdust" to fill in any large discontinuities in the surface and then covered the whole thing in some scrim foam that is backed with a 3D mesh fabric to stabilize the surface and make the underlying foam a bit more firm.
Seat foam12.JPG

Seat foam14.JPG

This will get put on the bike for some more butt testing just to make sure things are going in the right direction. Assuming I my butt is satisfied (don't go there,) patterning for a cover that fits this will be next on the agenda.
Seat update -

Patterns for the seat were produced and cover material cut out:
Seat Upholstery1.JPG

Those pieces are now sewn together:
Seat Upholstery6.JPG

And installed:
Seat Upholstery8.JPG

To be honest, I am not completely happy with what I ended up with. But, I learned a lot about how to do this by just getting this far and have some pretty good ideas of what I might do differently next time I need to make another cover. The results good upholstery trimmers get are pretty amazing, and I have an increased appreciation of the skills they have.

Normally I would give this another go as I have enough leftover materials to try again, however, I think it is time to focus on riding and this saddle will serve me just fine. I am crossing this effort off of the list and now just have a small punch list and some commissioning items to finish up.
wow bud. you have a lot of guts trying to tackle that. I admire your determination. my first 1978 was my favorite bike of all time. 2 years ago i found one like yours. Some filthy rich dude gave it to a kid next door. He put gas in it and started it. Been stored for 30 years. I bought it off him for a grand plus 100
@Jasonsblue81 - Nice looking original bike! That's worth the effort to get back in top shape.

As far as my efforts go, I had little to lose by going through everything as my bike was pretty original, but a smoldering pile of crap when I found it. At least I will know that all of the maintenance is up-to-date now! I have learned a lot too.
Here's Trusty Rusty about ready to fledge from the shed -
Trusty Rusty Leaving the Shed.JPG

Some before and after photos just for the record -
Right Front.jpg



Not so rusty anymore, but I did leave some tiny pieces of rusty stuff on the bike because I am not changing its name (you just have to look hard to find the rust now.)

It is time to get a plate on the back of this thing.
Well, I have had the bike out for a bit of riding and testing. It is working really well, except for three issues. The first was the oil pressure warning stopped working which I have traced to a bad connection in the headlight bucket. I also started seeing an aggravating oil drip from the bike. I finally traced it to the ignition pickup cover area. That has three potential sources - the two rubber caps for the left side rocker shafts (circled in the picture below) and the cam shaft seal. I replaced all of the oil seals on the engine except the camshaft seal because I couldn't find one. So, I cleaned up the old seal, said a quiet prayer and reinstalled it. There are now some NOS seals on eBay, so I bought one. I had previously scribed a mark on the timing plate so that I could take it off and get it back on in the same place (arrow below).

Cam Seal Leak1.JPG

Once I got the pickup off, I could see that the seal was definitely the source, so the seal was drilled with a small hole and a screw inserted to extract it with a pliers (sorry about the fuzzy picture of that).

Cam Seal Leak2.JPG

And the new seal was installed. The rocker shaft plugs have a looser fit that I liked, so those were degreassed and smeared with a thin coat of Motoseal before being pressed back in. Once everything was buttoned up, I took an hour ride to check out the results and the leak is gone. Now I have to clean up the oil drips all over our front pavers.

The third issue is I think the idle circuit is a bit lean once the bike gets really warmed up during a ride - the idle is slower to return to normal once the throttle is rolled off and it seems to be on the verge of hanging. So, I want to do one more round of carb turning and a thorough check for air leaks in order to try and clear that up.
When I did my re-ring, my cam seal was also leaking. I matched it to a Honda dirt bike front wheel bearing seal. I forget the exact model at the moment but it hasn't leaked yet. Just in case the nos rubber ages out on you.
I matched it to a Honda dirt bike front wheel bearing seal.

Thanks for the info, having knowledge of other parts that fit is valuable indeed as these bike age. I did take down seal and o-ring info for all of them on the bike while I was at it, just in case I got desperate. So many common parts were used by the big three manufacturers that there has to be a lot of places where parts will interchange (and maybe are cheaper to buy).