Originally Posted by
stapfam
Most of our organised rides have hills--Hills in the Plural -with grades well into double figures. One ride last year and 16%-followed by a mile long with average of 12% that has a good section with 20% and another mile long 12%. Then on another ride there was Brassknocker at 12% for 2 miles with a 23% section at just the wrong bit of the hill and the Grid Iron with the one rise that most dread with only 400 yards of 27%. Most of the organised rides-as I say- have hills that will challenge. I ride with a compact and 12/27 and don't walk hills but those that are not up to "Race" level fitness with standard double of 52/39 and a close cassette of 12/25 will struggle and even walk.
MTB's are slow and heavy but they do have the right gearing to climb a wall if necessary. Since going road I have always gone for Compacts and even have a 12/30 on one set of wheels and the Mountain bike is a TCR-C with a triple of 50/39/30 and a 12/25 cassette. I don't walk hills because I respect them and gear down for them. Have a ride in June that has 1 mile at 15%- an up and down of the South Downs that has 1/2 mile of 20% at the end and the High and Over and the name speaks for itself. 50 miles with 4,800 ft of climbing and the time for my age of 66 is 3 hours 40 minutes. It will be a struggle to do in the time for me and I will be using the TCR with the triple and the 12/30 will be going on for that ride.
Our hills may not be long but we have plenty of them and they can be steep. Couple a few of those with average riders on standard gearing and you can be walking.
Reminds me of when I bought my Klein. It came with road gears up front, 52x39 and a 13x23 cassette in the back. I took it out and tried it on a group ride and was able to keep up pretty easily even with the small rollers. The second day I took it to a rather short 3/4 mile climb shaped like the side of a bowl. It never gets to 15 percent but the climb increases all the way to the top till it gets close to 13 I believe. Before the top I had to stand and that wasn't good enough. I stood and started to paperboy back and forth to decrease the incline and that just got me to the top where I had to stop and sucked air and I was afraid to point my mouth down in case I were going to suck sand off of the pavement.

I switched to a 12x25 and I can at least climb the hill sitting down. Makes my Compact feel like I have a low range 4 wheel drive.