Dura-Ace 10 speed rear derailleurs are designed to handle up to a 27 tooth cog.

see, this is why i consult ST.

ok, so what do i gotta do? i have another bike, wider tires, also carbon, disc brakes, but quite a bit heavier. it has ultegra, and is 11 speed. i can throw my compact on there too, which makes it 34/32.

would that RD take a 34, does 36 even work?

the 10 speed is my parlee, which is light and stiff.

the 11 speed is a diamondback airen 3, it's not stiff at all, and not particularly light, d/t the wheelset and disc brakes.

Does your Ultegra 11 speed rear derailleur have an SS (short) cage or GS (medium) cage?

If you are currently running an 11-32 cassette, I would guess it is GS.

how can you tell?

is ss stainless steel, and gs galvanized steel?

SS is short.

GS is medium.

Really, the question is which hill/mountain are you climbing? You need lower gearing as the grade gets steeper. If the hill is a nice even 7% grade, you don't need extra low gears -- but it will take you longer hours to "summit". Steeper sustained grade is theoretically more efficient, but you will need lower gearing, and perhaps more attention on the descents!

https://www.strava.com/.../3544017673/overview

that's my friend who is organizing the ride, she attempted it this weekend and missed it by a bit, and she is the one that suggest 1:1 gearing. when in peak shape, i can suck on her wheel all day. but i'm not in peak shape, thus i tend to want to get the 1:1 gearing (there isn't better than 1:1, is there?)

thoughts, comments, suggestions?

i must be running gs then. the bike came with 11/32 in the rear.

That is not a very friendly climb for everesting, if the Strava segment profiles are accurate. There are flat sections in between steeps, so you will be working against air resistance and not netting any elevation gain. And the changing gradient means it will be harder to get in a rhythm, plus you will need low gears. Only you can tell how low a gearing will be sufficient. Why not ride it once to see how it feels if you are local?

If I were to do this, I would choose the lower 1.2 miles which is all climbing, and just repeat that. You can see your friend coast between the steep sections, HR drop by 30bpm and then start climbing again. This may feel nice, but it's much more efficient to turn around as soon as the steep climbing ends, recover on the way down and climb again.

i'm all ears. i have ridden it before. 3-4 times in the past. i just don't know shit about gear. i just get on the bike and go. until a few years ago, i never rode anything bigger than 25. 28 and 32 were eye opening.

so you suggest doing the beginning 1.2 miles? not the steep sections to the summit?

1:1 means that the front chainring is the same size as the rear cog. It's certainly possible to go even lower; most mountain bikes are equipped with far lower than 1:1, for instance, such as having a 34T chainring and a 50T big cog. Road drivetrains usually don't go so low, but it's certainly possible to go 1:1 and below on a road bike.

The important thing is that the gearing is adequate. If a stronger climber than yourself thinks that a 1:1 gear is reasonable, it wouldn't be a bad idea to err lower.

According to the Strava activity you linked, the steepest part is a ~.5-mile stretch near the bottom averaging >12% gradient.

The issue isn't that there are steep spots near the summit, it's that there's shallow spots in between them. When you're riding up a very shallow slope, you're having to push against more aerodynamic drag and rolling resistance per the amount of elevation you're gaining. For everesting, it's good to get the most elevation buck for your pedaling efforts, which means using a hill that stays at least mildly steep the whole way up.

You may want to consider using a Wolftooth Roadlink to fit a larger cassette on there. This will allow you to fit a 34 or even 36t cassette on your existing 7900.

Note that this will exceed the maximum chain wrap capacity of your RD. However, for everesting, where you will spend all of your time in the bottom 3-4 gears and in the small ring (and coasting downhill), you can deal with this by TEMPORARILY fitting a longer chain, and using the limit screw to lock out your top 2-3 gears to avoid going small-small.

by 7900, i assume you are talking about my DA setup. cus that's the bike i prefer to ride. ok..

lets say i get the wolf thing, i slap on a 36? or do you suggest bigger? when i rode it on 34/32 a few years ago, i really wish i had another gear, and i was in better shape than i am in now (and younger).

as for the segment. i was told that in order for it to be legit, you have to do the same stupid segment. 19x for 29,200, if i do the lower section only, that's like 40x!!!! my mind might melt.

john

The first mile has a 10% gradient, so it's quite steep. And you would have to climb it 54 times. That would be 108 miles total. You friend rode 102 miles, but still had another 30 miles or so left to go.

Here is Katie Hall's record breaking everesting, which I happened to flyby. She picked a 9% average segment, pretty consistent grade (first half is more like 10%), but no crazy gradients or switchbacks.

https://www.strava.com/activities/3501251017

so it boils down to 54x, or 20x... i bet after the first 5 laps. i'll really be thankful for those mini flats..

so lets talk about cassetts.. they don't make road down to 36. so i'll need one of those wolf things, and a mountain bike cassette?

You can buy a sram pg-1050 cassette on backcountry that is 11-36. You may still need the WT adapter though

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the world's still turning? >>>>>>> the world's still turning

funny, i was just looking at that cassette.

lets say i get the 11-36, and the wt adapter. could i pick up a mt bike front chainring that is... idk, 30 or 32 and run that?

also, what's the diff between the 1070 and 1050?

i feel like that'll really help on the steeper sections towards the last 25% of the day.

john

Running 34f-36r would have you at 5.23 mph with a cadence of 70.

On a 10% gradient, a 165 lb rider would need 215 watts to hold this speed. (You can play with the assumptions yourself at bikecalculator.com

i should be around 127lbs by the time june 20th comes around..

it says if i ride 158 watts, at 5.22 mph, it'll take me 25 hours to do it????

that seems off, it must not be accounting for all the down hills? should i divide the distance in half to get a better idea?

FWIW, I just Everested last Saturday and, with the exception of a ride two weeks ago, had never climbed more than maybe 5K feet during a ride. I'm generally a flatlander who climbs a few hundred feet per ride. It sounds to me like you've got plenty of climbing muscle memory built up. I wound up riding in the 34-32 pretty much all day. The hill I chose was 1.2 miles with 430 feet of climbing and two very short almost flat sections. 68 laps later, and I was done!

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Mike Sparks


I have competed well, I have finished the race, I have kept the faith.

how many total miles? i just started riding again after taking 2 years off.. lol. luckily, i generally am able to get into decent shape pretty quickly.

A mountain bike chainring wont fit on a road crank. So you are stuck with a 34 unless you switch to a crank with a smaller bolt circle diameter with a smaller inner ring.

1070 and 1050 are different levels of components. 1070 is a little lighter and more expensive.

You're in no form to attempt 29000 feet of elevation, even if it was virtual, charity or not. This is training forum, you have to train for challenges and youre a few years behind for this one. Train don't annihilate...someday you could do it...

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Strava

Absolute Black makes some great oval chainrings that are 46/30. I use them on my every day bike and can spin for days.