[Manning]

Looking to put some bigger tires on a '12 Defy 1 for gravel riding. One of the LBS's is doing organized gravel rides. Had one pinch flat on the stock 23's on a short stretch of gravel that connects some excellent paved roads.

Since tires are all over the place on labeled size vs. actual size, I'm looking for advice from people who have put larger tires on this frame/fork combo.

Appreciate any info.

 

[r1lee]

28 is my guess.

 

[Carverbiker]

I have put 32c tires on mine but they were very tight and I never rode them, but I ride 28c with no problem.

 

[Manning]

Thanks guys. Kinda what I figured. I've got one GP 4000s in 25 that measures 26mm, and after measuring all the clearances with it at both ends of the bike, I wouldn't be comfortable with anything bigger than an actual 28-29mm wide tire. The limiting factor in the rear is the brake bridge (radial), and the tightest clearance up front is the fork blades (axial).

So I'd guess a "real" CX tire is completely out of the question.

I'm guessing the local gravel ride scheduled for Saturday was cancelled due to the 6" of fresh snow and sub 20F temps...... I'm definitely too much of a wuss to ride in that, regardless of the bike.

 

[Manning]

Just in case anyone else with a Defy needs to know.....

Put a Schwalbe Marathon Plus 28 on the rear, and it clears the brake bridge by a millimeter at most. Measures 28mm wide. It does seem to be a very tall tire. The tread and carcass is extremely thick radially. It fit the front fine, was a little tight on the sides, but not bad. Also picked up a Specialized Armadillo in 28, and it measures 26mm wide at the most. A bit disappointed in that, but oh well.

 

[Carverbiker]

I use Conti GP 4 seasons in 28c if that helps. From my experience the touring tires are thicker in the tread area.

 

[smithmartin945]

Vittoria zaffiro 700c x 28c fit perfectly on my Giant Defy composite 3. Plenty of space between frame and brake caliper.