Turning Rotors?

Hey guys,
I called around and nobody local can resurface/turn my rotors. It's a '78 XS500 with front and rear discs. The rears work ok, but the fronts are weak. I've got new pads and was hoping to get a fresh surface for them to bite. Can I just sand them lightly using something very flat to back up the sandpaper?
Thanks

It can certainly be done. We have companies offering a refurb service over here in the UK.

A machine shop in town will most likely have a fellow sympathetic two wheeler working there. Get them on the lathe and turn them.

How bad are they?
I have cleaned up rotors with 220 grit sandpaper on an orbital quite a few times.
If you put the wheel (or better yet the hub) on a truing stand with the rotor attached the spinning of the orbital will spin the rotor and you can smooth it out without much fear of getting it out of round.

Thanks for the thoughts fellas - I like the truing stand idea, but I don't have one. The rotors weren't that bad - no pulsing / noticeable thickness variation front or rear. It's just that the fronts didn't bite for shit. I got new pads for the front and I wanted to give them something fresh to dig into when I get them on tomorrow.

None of the car parts stores or motor machine shops around here wanted to turn them, so while I had the tire off I just took some 180 grit that was laying around and lightly rubbed it in a circular pattern around the disc. I know that's kind of redneck, but I've done a fair amount of metal work and polishing and figured all I really needed was to break up the glaze and rust, which I was able to do - just barely and with a very soft touch.

I guess we'll see what happens. I don't think it could have made it any worse.

Send them to Tom at Truedisk.net. $45 for the grinding and 25 for drilling any design. $12 to ship it in a usps flat rate. He has 25 years of grinding experience. Pics of his work on my cb500 rotor.
Before after

Goodfella said:

Send them to Tom at Truedisk.net. $45 for the grinding and 25 for drilling any design. $12 to ship it in a usps flat rate. He has 25 years of grinding experience. Pics of his work on my cb500 rotor.
Before

after

Click to expand...

this is a screaming good deal and the only way to do it,really, you cant turn them easily in a lathe like a thick heavy car rotor

true disk is the way to go and a good deal. I had them do a set of disks for me and they did an amazing job. If you dont want to spend the cash and if they aren't warped you can hit them with some 80 grit sandpaper in a cross-hatching pattern or bead blast them to remove glaze-my personal choice. Don't use aerosol brake cleaner, they leave a residue that is a common cause of glazing.