Surfacing disc brakes

[Gene]

I have a 85 Honda cb650sc Nighthawk.
The front discs are grooved, and I'd like to get them surfaced. However, the local shop says that no-one turns them, just replacement. Is that true?

[Larry Fine]

Generally correct. Brand new discs barely meet minimum specs.

Yours would be too thin once turned.

[mollusc]

I turned the discs on my CX500, but they were thick monster things.  I just replaced the front disc on my NC700 and both the original and the new one were much thinner.  Not enough meat there to turn them and keep them in spec.

[Bob H]

The front discs are grooved, and I'd like to get them surfaced.

with 14,000 miles - how bad can they be?

It's not like some ancient high-mile car where the rivets dig into metal.
Granted sometimes you need rotors, but to put it into perspective I have 40,000 on my original NH rotors and this is with abraisive sintered HH pads for most of those miles.

My rotors are not polished smooth, but nothing I would describe as "grooved"

At any rate, I certainly wouldn't pull the wheel just to do a rotor with low miles.
I would wait for a tire change, or pad change unless the actual braking was affected.

[Gene]

Thanks everyone.

Bob, your right, it doesn't have that many miles on it. I like to be prepared before something crops up, so I thought I'd get some feedback. What I meant by "grooved" is I can feel the "groove", not so much see it.

[Bob H]

If you can't see a groove, then it is likely doing it's job.

... I like to be prepared before something crops up, so I thought I'd get some feedback.

Changing brake fluid once a year would be very proactive - many people go longer.
I wouldn't worry too much about the rotor. Wait until you need pads.

[Willie]

One of the few things I remember my HS Auto Shop teacher saying was that there's a benefit to NOT resurfacing a rotor, or drums, that had minor grooves. It was that technically speaking, the grooves provided greater surface area. Made sense to me. That's probably why I remember that little gem for so many decades.