Classic & Vintage - Max tire size for an 85 Trek 520???

Long term back burner project coming to fruition...This was the first year with the the cast livable and a sportier geometry. So the question is, what size tire can I fit with, and without fenders? I'm thinking 25 and 28? Thanks!

Cheers,
Chris

Hi Chris, I can't believe none of the Trek fans chimed in on this yet. I would suspect a x28 road tire would be no problem with or without. If your frendly with your local shop maybe they will let you experiment with some tires.

When building up my 1983 Trek 620 (which I've heard has ampler room than later years) I was amazed that 28mm tires barely fit under 45mm fenders.

My 2006 Trek 520 came with 32-622 tires and could have accommodated 35-622 without any problems, even with fenders attached.

If your '85 Trek has long reach caliper brakes, a size 700x28 may be the largest you can fit with fenders.

If your '85 Trek has cantilever brakes, a size 700x32 should fit with fenders.

Considering that the 1985 Trek touring bikes came with 27x1.25 tires, fitting a 700x32 should not be a problem.

Thanks a bunch folks! This is the 520 with Shimano 600 long reach brakes. It will probably end up with 25mm tires with 37mm fenders.

Cheers,
Chris

If your '85 Trek has long reach caliper brakes, a size 700x28 may be the largest you can fit with fenders.

If your '85 Trek has cantilever brakes, a size 700x32 should fit with fenders.

Considering that the 1985 Trek touring bikes came with 27x1.25 tires, fitting a 700x32 should not be a problem.


1985 Trek 520 came with 700-25 tires. I was surprised it did not have 27s, and side pull brakes. Specs changed almost every year, in 1985, the 520 was considered a "sport touring" model, while the 620 and 720 were the touring models they both came with 27 x 1 1/4 tires).

Meanwhile, the 1984 Trek 520 was in their touring catalog, had canti brakes, 27 inch wheels, etc. Odd move.

Gonna say 32mm w/ fenders 35 without.