Are these interference engines? I just found an exhaust valve inside my rt. Cylinder. Stem still in the head. Snapped off at the base of the stem.

[gggGary]

Those would be the 78-79 BS38, often called the best XS650 carb. So yes a 1978 XS650 Special.
Calipers the pistons are often rusted but the body usually cleans up fine, be sure to remove the rubber seal and clean behind it.
There's an excellent thread on rebuilding petcocks, factory parts 4 hole "valve" is best and available.
I'm big on Shinko tires, ordered one today. Others opinions will vary.

 

[650Skull]

Found a Partzilla screw up on the BS38 Carb semantic, 76/77 - 78/79. May be on the earlier BS38's a well
https://www.xs650.com/threads/partzilla-screw-ups.64963/#post-809566

 

[The Phantom]

Found a Partzilla screw up on the BS38 Carb semantic, 76/77 - 78/79. May be on the earlier BS38's a well
https://www.xs650.com/threads/partzilla-screw-ups.64963/#post-809566

Why in the world would it be drawn upside down? Must have been an engineer.

 

[The Phantom]

Those would be the 78-79 BS38, often called the best XS650 carb. So yes a 1978 XS650 Special.
Calipers the pistons are often rusted but the body usually cleans up fine, be sure to remove the rubber seal and clean behind it.
There's an excellent thread on rebuilding petcocks, factory parts 4 hole "valve" is best and available.
I'm big on Shinko tires, ordered one today. Others opinions will vary.

I’m seeing Clymer and Haines manuals, would you recommend one? Or the other? Or another? Thanks.

 

[Jim]

Yamaha factory manual