I just bought a 1985 trek 310 that is in great condition. It has diacompe brakes, double crank, 5 speed rear, downtube shifters and 27" wheels.

My only complaints are the rear wheel is out of true, the brake levers are akward to reach and don't stop great and the shifter hoods are pretty dang uncomfortable. I am planning on putting cane creek scr-5 brake levers on it, probably new brake calipers not sure what would be my best bet?, and was thinking about new wheels but not sure what hub spacing I would need and if they are readily available.

Any problem with switching to 700c wheels/tires or is the hub spacing gonna get me?

I'm kind of rambling sorry :)....I guess my number 1 question is can I use the cane creek levers with the diacompe brakes or should I get new brake calipers too?

Thanks

The levers will work with your existing brakes but it wouldn't hurt to get new brakes too.
If you get new brakes make sure you measure the reach on your current brakes. Road brake reach can vary from 39mm to over 60mm.. Measure from the center of the brake bolt to the center of your rim. That will tell you the reach you need.. Current road brakes are usually sold as Short reach(39-49mm), Medium(49-57mm) and long reach(57-74mm).
Medium reach brakes are sometimes called long reach so make sure you check the measurements.

Sheldon Brown is a good source

http://sheldonbrown.com/harris/brake-calipers.html

I switched my 81 and 84 Treks to 700C wheels; you'll have to fiddle with the brakes and possibly get ones with longer reach.
Good Luck and keep us updated

Thanks for the replies regarding the brakes guys.

Okay wheel questions.

I'm not sure if its 120mm or 126mm rear spacing, I'[m assuming its 120mm.

Anyone want to throw me a link or two to some good inexpensive wheels?

I just checked and its actually a 6 speed not a 5.

If it's a 1985 it'll be 126mm.

Thanks Richard.

I was eyeballing it with a ruler but didn't take off the back wheel to check for sure.

I just scored a beautiful 1982 Trek 750 and am thrilled with the bike... my beautiful old Bianchi donated some parts (Diacompe 500 brakes and levers, stem, bars, and her 27 inch Ambrosio wheels and Panaracer tires).

When I find some decent 700's I'll be installing them as it will open up a wider world of tire options.

I paid $30.00 Cdn for the frame which came with a clean bb and headset and a Suntour BG
group which is the Cyclone touring version.