Fatter tyres

[Commute addict]

Hi Folks,
I have an older Giant CRX1, running Shimano 622 x 15c Rims and 700 x 28mm tyres.
Can I fit 32mm tyres on it? Some of the tables I have looked at suggest so.

[10speedsemiracer]

You can fit 32s but it sort of depends on the 32. A Vittoria Randonneur for example may sit big on a 15mm rim and be a bit roley-poley whereas a Maxxis Re-Fuse may sit a bit smaller. These are just examples.
I don't think you will experience much difference in comfort 28mm-32mm on the same rim but I do think you will feel a slight handling deterioration.
I would have thought that a 32mm was just a smidgen too big for a 15mm rim.

[uart]

Hi Folks,
I have an older Giant CRX1, running Shimano 622 x 15c Rims and 700 x 28mm tyres.
Can I fit 32mm tyres on it? Some of the tables I have looked at suggest so.

32c tyres fit those rims, but they're at the upper limit. So they will tend to "bag out" a bit, and the handling may feel a bit squishy. As 10speedsr said, there's differences in sizes between brands so not all 32c tyres are the same.

Just as important as the rims however is to make sure there is enough clearance on the bike itself. Take a real good look at how much clearance that you have on both the front forks and the rear stays (current tyres fully inflated). Look at the lateral (side to side) clearance on the fork and stays, and also at the radial clearance at the top of the forks/brakes on the front and at the brake stay and BB stay on the rear. If you don't have at least 4 or 5 mm clearance in ALL of those places then forget about it.

[Bentnose]

I have 40mm tyres on my 15mm internal rims, handling is a bit squishy but otherwise fine, I'll get bigger rims one day.

[Duck!]

As far as frame & fork clearance, 32mm will fit fine. Even 35s will fit. Where you can get hung up, particularly on the lower-spec models which use triple-ring cranks & MTB-derived mechs, is front derailleur clearance.

But as others have suggested, getting to the limits of what will go on the rims.