I have been googling cycling in California and doing those big climbs like Sonora Pass and Tiago and it fascinates me the flatlander. I am generally a strong cyclist but wondered if these can be done just on a whim. I have done some climbs visiting and I do struggle with but never have had to walk up anything yet. Around these parts I run an 11-23 or 11-25 compact and the biggest climbs I have dealt with are maybe 1 mile at 6-7% grade. Doable but not just simply easy. I thinking of doing a vacation and trying ride some of these climbs and wonder if mortals can do them just on ordinary training. I ride about 100 miles a week but also run long distance since I am runner first of all. if I am not running I ride 200-260 mpw. I thinking with a 12-32 ( 50-34 Big) I could do the Sonora Pass and make it without too much struggle, but I am lost. If I do a 70 mile ride like yesterday I managed only 1700 ft of climbing on my Garmin 910. That is nothing compared to what I see on Strava for some rides. Now I certainly average a good pace in comparison 18-19.5 mph but again seems nothing in comparison.

One way to predict climbing performance on a yet to be tried route is to determine your VAM on your local climb.

Then use strava to check the route you intend to climb. Look down the leaderboard for athletes who completed it with VAM similar to yours. What was their speed up? If it's a speed similar to what you have available with your current gearing, then you should be OK.

Having just returned from Breckenridge (elevation 9600ft), I doubt Tioga pass is ride you'd want to try unless you've done a fair bit of climbing. In addition to the raw climb, Tioga pass is at 10k ft, so you lose a significant fraction of your aerobic ability. With enough gearing, you could eventually make it up, but you may not like the suffering.

Having driven up to and through Sonora Pass dozens of times, I know that it's elevation is around 9600'. You'll be working hard at mastering that mountain pass.

Do you have a power meter? If so, you can make a decent estimation based upon the % grade, your weight to power ratio and bike gearing.

Sonora Pas is ~9600 feet, about 300 ft lower than Tioga.

[Edited to add:] I've never done Sonora but I've done Tioga on probably about the same volume of riding as you. However, that was when I was 19 years old and stupid. My buddy and I rode up to Yosemite Valley from the Bay Area in one day, where we met up with his folks who were staying in Yosemite Lodge, so we got to shower and eat well and sleep on soft beds. Then we hiked up to Half Dome and back to the valley the next day. Then we rode up to Tioga Pass and back the day afer. You can get away with a lot when you're 19 and stupid.

You're never really going to know until you go try some climbs like that. People react to altitude in different ways, and some won't be bothered by 10,000 feet, while others wilt at much lower heights.
Your idea of a 34x32 low gear is good. I've climbed in the Sierra Nevada with a 30x28 low and I'm fat and old.
Stay within yourself, be sure to eat and drink enough, and be as prepared as you can.

Sonora is really steep. Tioga is not as steep but is very long and high, and the scenery is insanely great especially near the top. Don't ride in Yosemite valley it's a death trap, everyone is looking at the rocks and not the road. Do go there to hike and sightsee, though, if you are in the area.

I would recommend Monitor or Tioga, both from the west side. Look at the Death Ride web site for info on the passes around there.

Donner pass is nice too. Riding near Tahoe is tricky because there is so much traffic.

34x28 low gear is probably ok, but if you can get the 32, may as well.

Don't underestimate the effects of altitude, you should probably train as much as you can before going.

Do go though, the sierras are beautiful.

I rode Donner Pass with 35 pounds of gear on my bike, 35 years ago when I was 20. I had a 29 inch low gear - 32 cog, 34 chainwheel, and was riding a 24 pound steel bike at the time. But I did it on the tail end of a trans-America ride where, in the prior couple of weeks, I had already ridden up Trail Ridge Road in the Rockies via the Big Thomson River Canyon (over 12.180 feet), Rabbit Ears Pass (over 9400 feet), and Guardsman Pass in Utah (over 9700 feet) - all of which were quite a bit higher and tougher than Donner. Certainly, Trail Ridge Road was the toughest of these, by far, due to the overall amount of elevation gained, the overall altitude, and the fact that not only was it the biggest climb of the entire trip, it was the first big one as well. We did the Trail Ridge climb over three days. We did the climb from Ft Collins to Esties park, where we gained 2700 feet and then took a day to go siteseeing and aclimatize to the altitude at about 7700 feet. By far the toughest part is the climb was from just after Estes Park, to the Trail Ridge Summit, where we climbed from 7700 to 12180 feet - a 4500 foot climb from the 7700 foot starting elevation. It should go without saying that as we had already ridden from the East Coast to Colorado, averaging 75 miles a day loaded with 35 pounds of gear - we were already in shape by then (and, 20 years old). Still, on Trail Ridge road, we probably had to stop and take at least a 5-10 minute breather every 500-800 feet of elevation that we gained - typically every 3-5 miles.


After we had Trail Ridge Road under our belts, the other passes were a piece of cake, relatively speaking.

I stand corrected and should have verified my numbers. Original post has been edited. 8)

gorgeous scenery and screaming descents. as for the ascents...if the elevation gets to you, you can always put a leg down to take a few pics
here and there. no shame in that. nothing really adequately prepares you for riding them other than getting your feet wet and riding one or two.
hydrating/eating properly helps immensely as does dropping a few lbs (if applicable) beforehand. east side sierras are magical. enjoy.

And the fresh mountain stream water tastes utterly great!

Tioga Pass is gorgeous. Do this one. I'd probably start at Mono Lake and ride up to the meadows, it'll be pain but the scenery will distract you.

Altitude hits different people in different ways. If you can, take a couple days to acclimatize before the ride. Go hiking if you have the time, even with the crowds Yosemite is a magical happy place and you can't go wrong.