Need to remove tubular before truing??
 

I got some old tubular wheels in my garage. They need to be true. Never done it. Can I keep the tire on for truing?

thanks.

Of course. No need to remove sew up. But be sure to check the glue well before you ride it. Old glue gets brittle, so pump the tire up until it holds its shape and then try as hard as you can to roll it off with both hands.

what's the difference between a sewup and a tubular? I thought they were the same. How can I tell what I have?

Exactly the same thing. Us oldsters, who used them exclusively in the late 70s, early 80s call them sew-ups, you y'ungins call them tubulars.