Rescuing Dad's '71 XS1B

MNiceGuy

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Hey everyone!

I had to take the clutch side cover off and that gasket was bonded to the case to a degree that I have never seen before. I tried every method I could think of to get the old gasket off and ended up finally resorting to acetone and a carbide-tipped chisel. I have plastic scrapers but those were completely ineffective.

After spending 2 evenings being very slow and very careful I got the gasket material off but not without some scratches here and there. In a perfect world I would have had the case blasted but for now, the engine is staying in the frame.

What are my options? Go for it and see what happens? Is there some way I can somewhat restore the surface uniformity?


About Me

Since this is my first post: I just recently acquired a 1971 XS650 that my dad bought brand-new in March of that year. When he was younger he did many long-distance trips and finally put it to rest with 24K miles on the clock.

It was parked sometime in the 80's and last ran in 2005. Today, it's clear there are a handful of things that need attention before it goes back on the road. That's what brings me here so expect to see more posts from me as time goes on.

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Next time you're removing old gaskets use paint stripper, and on aluminum I scrape them with a length of flat stock aluminum.....around 3mm thick, 2" wide, 8" long thereabouts.
You may have to use a gasket seal to fill any gouges. I might be inclined to the old Permatex original non hardening goop....other opinions may vary.
Welcome aboard!
 
First , Welcome

Nice survivor and very cool it belonged to your dad.

As far as the gasket goes I would take 400 wet or dry sandpaper to lightly smoth the surface and the use the recommended yamabond or equivalent to seal it.
 
I 'think' the old gasket was bonded to the case. Generally speaking, is a sealant recommended for the side covers and other things like the valve adjust ports?

For using a stone or wet sandpaper: might be dumb question but what method do you use to avoid getting particulates or abrasives where they shouldn't be?
 
I generally don’t use any sealant where it isn’t specified.

Removing material from the case is not a good thing. I suggest the stone for removing high spots where your tool did damage. The gasket should handle the rest.
 
what method do you use to avoid getting particulates or abrasives where they shouldn't be?
Stuff clean rags everywhere and finish the process with a vacuum cleaner (don't tell Mom/wife). I prefer to knock down the high spots with a large, fine tooth flat file - used judicially. As mentioned, the gasket should handle the low spots and I would put a light coating of white lithium grease on the gasket.
 
You have a very nice survivor there. Not many in the good of condition. gaskets of that age are hard to get off. Just take your time. I tend to wipe on acetone and then scrape with a razor, then another soak of acetone and another(you get the idea) but still takes hours. I have tried gasket remover but not to much success either. I use a diamond hone to gently go over the surface after the gasket has been removed. You can buy them at some Home Depot stores. They are pretty good size 6x2 and will allow contact across the case so you don't round off or take to much off one area. Just a little wipe will show high or low spots. I have been using Loctite 518 on my gaskets and been happy with the results. I have used no gasket sealer, grease,non hardning Permatex but have settled on the 518.
 
Greetings from Arizona and welcome to the forum! This is a great story and a nice , complete early bike you have to rescue. You might want to think about changing the title of this thread to something like, Rescuing my Dads old XS1B , or something, and keeping this rescue effort all in one place. We all love a good save, especially on an early bike, and you could post all your photos and questions here , all in one easy for us to follow location! 🙂
Good luck with your Dads old bike, I hope you can get er going again!
 
You have a very nice survivor there. Not many in the good of condition. gaskets of that age are hard to get off. Just take your time. I tend to wipe on acetone and then scrape with a razor, then another soak of acetone and another(you get the idea) but still takes hours. I have tried gasket remover but not to much success either. I use a diamond hone to gently go over the surface after the gasket has been removed. You can buy them at some Home Depot stores. They are pretty good size 6x2 and will allow contact across the case so you don't round off or take to much off one area. Just a little wipe will show high or low spots. I have been using Loctite 518 on my gaskets and been happy with the results. I have used no gasket sealer, grease,non hardning Permatex but have settled on the 518.
That's exactly what I ended up doing. Acetone soak, then scrape - over and over again for hours and hours. I put the sump cover in my ultrasonic (which will strip paint under the right circumstances) and the gasket didn't even blink. I've had stubborn gaskets but the ones on this bike are on a completely different level.

Ideally I would have been able to get through it without leaving any marks but that just wasn't in the cards. Whether it be a razor blade or a chisel it doesn't take much to leave a scratch in aluminum.
 
Greetings from Arizona and welcome to the forum! This is a great story and a nice , complete early bike you have to rescue. You might want to think about changing the title of this thread to something like, Rescuing my Dads old XS1B , or something, and keeping this rescue effort all in one place. We all love a good save, especially on an early bike, and you could post all your photos and questions here , all in one easy for us to follow location! 🙂
Good luck with your Dads old bike, I hope you can get er going again!
My first step was to make sure it ran smoothly so I knew just how much of a project I had in front of me. Both carbs needed a rebuild but after that it fired right up. I set them up per the guide here (a godsend by the way) and it purrs like a kitten.

This bike lived in the front of my parents' garage and we're thinking dried road salt (Minnesota) was finding its way to the XS from the garage floor. The chrome had surface rust and anything that was polished/brushed aluminum was pretty oxidized. This isn't going to be a Concourse De Elegance machine but as long as it's safe and reliable I'm happy.
 
As mentioned, paint stripper works well for removing old, hard, stuck on gaskets. "Paint" it on, let soak for 10 minutes or so, gently scrape off the portions of gasket that have softened, repeat. It usually takes several applictions to get all the old gasket off, but you won't do any damage to the sealing surfaces.
 
Well I did as everyone suggested and took care of the high spots whilst leaving the other scuffs alone. I slapped on the new gasket, dry, and torqued to 7ft lbs. No leaks so far! Whew!

In other news, I'm getting a rather pronounced ticking from the left side of the engine, up near the head. The right side is much quieter. I checked with my dad and he said the valve lash has never been checked. I have 0.012 and 0.004 feeler gauges so I'm thinking it's time to look at the valve lash. Am I on the right track? Just the thought of scraping more gaskets.....

Season 2 Smh GIF by The Lonely Island


This '71 does not have the linked carbs so each one has to be dialed in separately. I plan to use the exhaust pressure method to check this. I think I have them somewhat close though.

Oil level is good and oil screens are new/clear. Using 20W-50 Yamalube currently.
 
It's become accepted practice to use .003" intake and .006" exhaust on the valves for all years. That .012" on the exhaust will probably tick just as bad as it is now, lol. You should also check the cam chain tension. It can sound like loose valves if too loose.
 
Thanks for setting me straight on those valve clearances. I don't know how I got that mixed up. They were actually pretty close with the exception of one of the intake valves which was at 0.007".

@gggGary - I never thought of rounding the edges like that. I will have to try that out!

I got everything back together and took the XS out for a 20 mile ride. I'm happy to report that the bike didn't let me down. I was originally planning on doing a more extensive restoration after I was able to verify the basic mechanicals but now I'm reconsidering. I like the idea of it being a "survivor". I have a couple more things to finish off and then I'll get some pictures up.

Thanks everyone for the help so far!
 
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