Sierra_rider

I agree, nothing really extreme with the gradient. Depending on the OP's fitness and ability to handle altitude, he might not even need the climbing gear of something like a 50/34 and 11-34 combo. Although it is nice to have a bail-out gear available on the climbs.

Sierra_rider

My primary road bike is my "climbing" bike so I do have the 12 speed, 50-34/11-34 combo on it. If I didn't live in a climb-fest of an area, I'd either have a 11-30 on the back or run the now-standard 52/36. However, virtually all of my rides are above the golden ratio of climbing, so granny gears it is.

FBinNY 

I'm an eastern rider who grew up near the second hilliest city in the USA. I'm very used to short to medium length steep hill, which I prefer to attack in a reasonably, but not very low gear, then recover before the next one.

So, I'd be fine with the gearing the OP has now. However 20+ miles at 3-4% would severely try my patience, and I doubt I could solve that gearing.

PeteHski

+1
That is a lot of sustained climbing and a 1:1 ratio will be very welcome on those 10% ramps and even when tapping away up those long, long relatively shallow climbs. People often underestimate how much power you can actually generate in a low gear at a normal cadence on a 5-6% slope. It’s nearly always better than grinding away at 50 rpm in a higher gear - especially on a 27 mile climb!

I just rode a simulated profile of Mt Fuji which averages around 5% gradient for 25 km. I had a 48/35 chainset and 10-33 cassette. I rode the whole thing using mostly the lowest 3 gears at an average 230W. I only used 4th and 5th gears for a few short standing stints and flatter sections.

big john

I see 105 10s compact cranks brand new on flea bay around $100. If that would work with your bb, I recommend it. I have a 34x29 low gear and I climb with it and I'm old and fat.

datlas 

I am trying to be tolerant, but why does the OP post the question twice and not give us the additional info we need (and requested) to give a decent answer to the question?

FBinNY 

This is Bike Forums, OPs opening duplicate threads, ie. in general and mechanics, while not par for the course, is still very common.

Let's just chalk it up to newbs covering their bets because they don't know which sub forum is right.

DaveSSS 

What you need for gearing depends greatly on your age, fitness and body weight. I've been riding the Colorado mountains since 2003, when I was 50 years old. Back then, 10 speed was the only and best option. I changed to 53/39/28 triple cranks to go with my 12-25 or 12-29 cassettes.

Average grades don't mean a thing if you can't get up the steepest climbs. Even 4% will start to feel tough if long enough or if there's a head wind. I came back to cycling after 8 years of in 2818 at age 65. I had 11 speed in 2010 with 50/34 compact cranks. I still had one bike with those cranks and a 12-27 cassette in 2018. That wasn't low enough for a 10% grade so I got a 48/32 crank and 11-34 12 speed Campy setup. Until recently I had Shimano GRX 46/30 cranks with SRAM AXS 10-36 cassette. The older I get, the lower my gearing goes.

As someone else noted, the 46/30 GRX cranks would help and they're cheap if you can find leftover 10/11 speed models or good condition used. The only issue is the chain line. You'll need 2mm spacing washers behind the 8 chain ring bolts to move the rings inward. I have the 12 speed model on 3 bikes.

tomato coupe

You really should spend some time to learn a tiny bit of math. If the OP added only 1 tooth on the big end of his cassette, the effect would be much larger than the added weight from the heaviest disc brakes.

jonathanf2

I like 50-34t/11-34t on 12 speed. Low gear ratios are almost similar to an 11-32t in 11 speed. I think with 12 speed, this combo has the best road gear climbing combination. I also have a 48-32t chainring ready-to-go if I decide I want more climbing gears. Though I find 52-36t to be smoother when it comes to cadence, but I don't like the bigger gearing gaps with an 11-34t 11 speed, so I stuck with 11-32t 11 speed.

My gravel bike is running 46-30t and 11-36t cassette. I can climb most mountain trails with this combo, but there are times I wish I had something like a 44/42-28/26t chainring. I prefer an 11-36t cassette mainly because anything bigger doesn't feel as concise when shifting on a 2x setup.