1980 XS750 Build Thread

Picked her up for $100 bucks!

1980 xs850 with a 750 engine.

This is what she looks like today.




Not a whole lot of time to work on her today but I did find time to tap the petcocks for manual conversion

What is this operation you did on the petcocks with the taraud (I only know the french name, tap and die appararently but it seems weird) ?

Tap and die is correct😁. You can read about the process at the below link. You tap the center hole so that you can thread a bolt to block that passage.

Petcock Conversion

Thanks I didn’t know about this particularity ! My xv500 already had that system with the “PRI” position that I’ve never understood, I even one ended out of gasoline after the reserve position failed me…maybe I should modify it the the two bikes.
I might get back to you when I get to do it, there is some vocabulary for which the author used abreviations I wouldn’t want to mess up my taps.

Thanks !

Pardon my lack of vocabulary in english…
Can omeone explain the following sentence from the link rendmoto gave me earlier :

“Get an 8mm Allen headed bolt in the drill (Hold the drill in a vice and use a file to machine it down) or lathe and turn the head down till it’s less than 10mm round. Make sure you put a taper on the inside edge as shown.”

I think I understand but I don’t want to mess up, problem is the guy who wrote used reeeaaal generic words :

  • to drill means to “make a hole”, in this case it doesn’t make sense
  • apparently a vice is what I would have called a clamp for example, it’s confusing since in french “une vis” which would be a screw
  • a file to me is, well, a file but I get what it is in this context
  • machine it down : welle I get it but poor choice of words
  • “or lathe and turn the head down” : no idea

Basically you need to lathe the head of the bolt down to less than 10mm in order for it to fit down in the petcock

Little bit of painting today



Finished priduct!


Fresh bearings!


Man that looks good. You can rebuild my engine next.

Thank you!

I made some good progress today. Replaced all bearings and brought the cases together. It’s getting there.




Awesome progress you have going on here. Following your build.

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