polymorphself 

Looking at photos, and assuming it is a touring model with cantis, I'm assuming the fender clearance is decent even with 27" tires, but need to be sure. Only pic I have (not mine)

Thanks!

polymorphself 

Bump!

The Golden Boy 

crank_addict !!!

polymorphself 

Gotta be somebody around with some insight!

Cycle Tourist

Looks like there's plenty of room. Anything that doesn't rub is perfect.

due ruote 

I had one for a while. Great riding bike. If it had been a size down I would have kept it.
I switched to 700c and ran 32mm with fenders and had lots of extra room, but I doubt that info helps much. Sorry I cannot be more specific.

Road Fan

I have a 1984 Trek 610, and it has 53 mm fenders between the seatstays. The gap between the chainstays is narrower, and the fenders are cutout somewhat where they go between the chainstays. It might be good to trim just a little more, depending on the frame and the fender. The fork clearance is not a part of it for me, because I have a custom fork on the bike. But for the rear, you should be able to get a 53 mm fender in there considering seat stay clearance, and that YMMV. I once measured the chainstay clearance at the point where the tire is widest. I don't recall the actual number but it was in the 40 to 50 mm range. So the widest tire that I have comfortably fit with the fenders measures 31 mm. If I had a pair of 35 mm tires and some 38s, I might think they are fine. The same principles apply to the fork as well.

If you measure the actual space between the chainstays at the point where the tire is widest and allow 3 or 4 mm clearance to the chainstay on each side, that is the space that a well-maintained wheel should be able to run in. Maybe you should have a wider gap for a touring bike because of the heavier loads and reduced chance to get a big repair done on the road. I do not think Trek put more clearance in the 520 frames than they provided on the sport-touring frames like my 610.

Chr0m0ly 

I have some ‘83 and ‘84 Trek tourers, but they come from the pre-fastback seat stay stay era, so I don’t think that info would be helpful.

They all fit, at minimum, 28mm tires with fenders. I would speculate the ‘87 model year would be the same, and I’d imagine by ‘87 they would allow for a 32 with fenders, but I don’t have any treks newer than ‘84.

The brochure specs 27 1 1/4 tires, which are roughly 32mm wide, so I think you’ll be good.

polymorphself 

Thanks for the info everyone. A friend across the country was picking this up but we wanted to be sure she could get fenders on it as she'll have a lot of snow and rain. All indicators pointed to yes to me but without being able to see it in person I wanted to get some second opinions. She did end up picking it up and its pretty awesome. The paint is wonderful. Sorry for the NDS photo and the kickstand This is as found.

Road Fan

Actually 1 ¼ is pretty much exactly 32 mm. The lateral clearance with 27 x 1 ¼ should be real good, but the radial is at least 4 mm less. If you have 622 x 32 and 630 x 32 the widths will be the same but the radial clearance is 4 mm less. Worse for 35 mm or 38 mm tires. Will they rub? I don't know.

I would totally agree it will fit 622 x 28 with 45 mm fenders, and most likely 32 mm tires as well; my Trek will fit 31 mm nicely. Not sure about 630 (27") x 28. The opinions about radial clearance are quite varied, and it might be the reality is, as well.

polymorphself 

The widest she is likely to run is 32mm tires with 45mm fenders.

gugie 

As others have noted, fork clearance is more than adequate.

There's only on picture that shows the chain stay bridge, that looks a bit tight, and I can't see the seat stay bridge (normally a brake bridge, but in this case it's a cantilever system). Just double check that.