So I have an 82 trek, I been having issues with wheels( keeping them true and such) only because I can only ever find the el cheapo wheels. So is there some good 27"s I can get my hands on or would be better to switch to 700c and take advantage of the new technology. I do know what goes into the switch, but I'm planning on replacing all of the parts on the bike as the are 30+ years old.

I also hop a lot of curbs and rough terrain( bike messenger) I just can't ever get any good info on 27" wheels so I'm having a hard time making my decision. Just looking for guidance.

Thanks.

I would do it without hesitation.

Few tire options remain in 27 " but the tire companies may make 1, each.

a radial brake reach down 4 mm is required. diameter difference 8.

The main caveat is that 700c rims are slightly lower-diameter and thus your brake calipers need to be able to reach 4mm farther. You'll have to move the pads down.

the only down side is making sure your brake's calipers will reach the rims . 700 wheels are shorter compare to 27 .

I have done that for about half a dozen bikes over the years. I do it both to keep all my bikes on the sane wheels (at least in front) and also to allow bigger tires and fenders. I usually put a Mafac Racer caliper in front, nicely taking care of both the additional reach and giving good wet weather stopping power. (Most of these bikes are/were all weather commuters.) Also quickens the steering a small amount by reducing the trail which I like as I ride with very long stems.

Ben

If you're going to replace the wheels, you might as well go 700c. There's nothing inherently wrong with 27" rims, but you'll have more 700c options to choose from. And a significant number of 27" rims will be mated to freewheel hubs which aren't typically as durable as the freehubs you'll find on most 700c wheels.

The things you'd need to take into consideration is needing to spread the stays to accommodate a 130 mm hub and ensuring your brakes can reach 4 mm longer than they currently do.

this
If your bike is 126mm rear axle spacing, you can easily spread it to 130mm without cold-setting it, giving you 8-, 9- and 10-sp options.
The tire choices for 700c make it worth it. The tire choices for 27" make it not worth replacing a 27" wheelset

700C wheels are available with 126mm-spaced freewheel hubs if that's your bag, too.

Sun CR18s come in a 27" size... they should handle all the curb hopping you could expect to do.

All those other considerations are for if you're really in love with the idea of modernizing your old bike.

Agree with the others that this is an easy and sensible conversion. You can get quality alloy 27 inch replacement wheels though:

Sun CR18 27 5,6,7 Speed Freewheel hubs Road Bike Wheelset [72274726665] - $115.00 Velomine.com : Worldwide Bicycle Shop, fixed gear track bike wheelsets campagnolo super record vintage bike

this is actually a great way to improve an old bike boom 10-speed.
It does require you cold-setting the rear triangles to 126mm, but will let you go up to a 7-sp freewheel.

This is the part that caught my eye. I understand the impulse. I've got several vintage bikes that I installed new components on, and an '82 Trek should lend itself very well to such an upgrade. That said, depending on which model it is the parts you have could be nice. There are some components being made today that I'll be worried about when they are 30 years old, but the components that were made during that time are built to last. If you decide not to use them, consider cleaning them up and selling them.

Now back on topic, I've got an '82 Trek 614. I'm using 27 inch wheels on mine and it still requires longer reach from the brakes than you get from most brakes from the big three component makers these days. Standard brakes now max out at 49mm of reach. I'm using Tektro R539s on my Trek with 27 inch wheels. These brakes have a range of 47-57mm reach and I think I'm about in the middle of that range. With 700c wheels I'd be at the end and I might even need the longer reach R559's.

The 700 and 900 series Treks from that year were sold with 700c wheels, but if you've got 27 inch wheels now you probably have a 400, 500 or 600 series frame and so I would guess that your brake reach issues would be comparable to mine. As I noted above, there are good brakes available that will make this conversion work for you, but you'll need to look for them. The other thing you should be aware of is that you probably need nutted brakes (as opposed to recessed) or you will need to have your frame drilled out for recessed brakes. I recommend looking for nutted brakes since that is an option for the brakes with the reach you need anyway.

Finally, if you decide to stick with 27 inch wheels for any reason, there's a guy selling a really nice set right now over on the Classic and Vintage sales sub-forum.

Unless there is a really good reason to replace a bunch of components; I'd build up a set of 630 wheels with Dyad rims. Velocity Wheels - Hand Made in USA

If you really want 622 wheels, I'd go with Dyad or NoBS rims. Velocity Wheels - Hand Made in USA
Velocity Wheels - Hand Made in USA

given your curb hopping and rough use.

I would go 700c if the brakes reach. The only reason to stay with 27" is to reuse your old tires, at the cost of having to use 27" tires in the future.

Excellent points. I have an '83 Trek 400, bought used, that I updated to 700c wheels several years ago. It came with "long reach" (47 - 57 mm) Shimano 105 dp brakes (added by the previous owner) that had enough adjustment to align with the new rims. These were nutted brakes so no drilling was needed but I have drilled out other frames to use recessed nut brakes that originally required external nut mounts.

I'd switch to 700c-- I have done that to both of my bikes that had 27 inch wheels. I reused the old hubs and built new wheels with Sun CR-18 rims and new Sapim spokes.

...if you really need to keep hopping curbs, and like most bike messengers you only use a couple of gears ( I guess that depends on the city you work in), you might want to consider going to a wheel/ hub combination that frees you from rim braking.

You can build a pretty bomb proof 700c wheel using a box section rim like Alex Adventurer or Sun CR18, and couple it to a SRAM two speed Automatix hub with a coaster brake. It's not quite as good as having brakes front and rear, but you guys just go around stuff anyway, right ? the 700c rim ought to give you room for a little fatter tyre in the frame, too.

You have to fool around a little bit with figuring the gearing that's ideal for you, but I have this setup on a track frame here, and it seems to work OK with just the coaster brake....and you can do way cool skids with it. It's not real practical if you need some gearing range, but it's better than single speed, and if the wheels go a little off it's not a big deal.

Another good point. When I went to 700c wheels on my '83 Trek 400 I was able to fit 700-25 tires with fenders. There was no way the fenders would have fit with the 27" wheels. Larger tires would also have fit if I hadn't had the fenders.

shimano long reach brakes are nice

I'm using these to run Ultegra 6600 brakes on my old Trek.


BDop OFFSET HOLDERS

If it was my bike I'd borrow a set of 700c wheels from somebody and test fit them to see what needed to be done to make them work. You might not have to do anything but adjust your existing brakes. You might not be able to get even long reach brakes to work.

If you are looking at replacing a lot of parts, cost out the project first. It might be more cost effective to get a different bike.

you need to be able to move you brake pads down 4mm - that's pretty easy to eyeball
(these are Kool Stop Dura cartridge pads on a 700c wheelset on my 40-y-o Raleigh)


even then, if necessary, you can buy offset pad holders
https://www.bdopcycling.com/BDop%20Offset%20Holders.asp

I've looked at those. They're a little spendy but they offer a great solution. What do you think of them?

Yes spendy, but I'm very happy with them. High quality, concave washers for easy toe in, quick delivery. This was a bike originally running 700 and even filing the slots brakes barely reached the brake track, now there is plenty of slot left. It's my commuter so it sees lots of use and I could justify the cost especially after updating it to 10 s Ultegra drivetrain.