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Hill climbing gears Mt Washington?

Old 02-26-20, 07:51 PM
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Water68
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Hill climbing gears Mt Washington?

Hello New here, was hoping to get some help with gearing on my bike for Mt. Washington Hill climb. I was thinking of going with 34T ring with 11-40 cassette, Iam limited to 34t ring with existing crank sram force 1.
This would put me at 1 to 1 and then some lower gears for bail out. This is my 1st attempt at the Mt Washington hill climb, I am looking to complete under 90 minutes. Thank you in advance for every ones input. Water68.
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Old 02-26-20, 08:15 PM
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https://pjammcycling.com/climb/8.Mt-Washington-Auto-Rd
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Old 02-26-20, 08:17 PM
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Originally Posted by Water68 View Post
Hello New here, was hoping to get some help with gearing on my bike for Mt. Washington Hill climb. I was thinking of going with 34T ring with 11-40 cassette, Iam limited to 34t ring with existing crank sram force 1.
This would put me at 1 to 1 and then some lower gears for bail out. This is my 1st attempt at the Mt Washington hill climb, I am looking to complete under 90 minutes. Thank you in advance for every ones input. Water68.
It's nothing to do with gearing other than with how long it will take you to get to the top. It is about gearing that will allow you to get there. A first attempt at such a difficult climb should be about getting to the top. Do not worry about how long it takes. This climb is so brutal that you will not be allowed to ride back down after the climb. What does that tell you?

Last edited by alcjphil; 02-26-20 at 08:22 PM.
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Old 02-26-20, 09:11 PM
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Do you know what it's like to ride a 12.1% gradient? For 7.4 miles? That's what you need to figure out. Figure out what gear you can comfortably ride at 12%. For 90 or so minutes. 12.1% is pretty steep in my book, especially over an extended period. And you may want to research what the maximum gradient is because I've only talked averages, and I'm pretty sure there are times you hit 19%, although I think those are short stretches. I would certainly have a gear ratio under 1:1 and you're well below that.
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Old 02-27-20, 11:22 AM
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Originally Posted by Water68 View Post
Hello New here, was hoping to get some help with gearing on my bike for Mt. Washington Hill climb. I was thinking of going with 34T ring with 11-40 cassette, Iam limited to 34t ring with existing crank sram force 1.
This would put me at 1 to 1 and then some lower gears for bail out. This is my 1st attempt at the Mt Washington hill climb, I am looking to complete under 90 minutes. Thank you in advance for every ones input. Water68.
Got you covered <running, ducking>
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Old 02-27-20, 11:29 AM
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Originally Posted by Water68 View Post
Hello New here, was hoping to get some help with gearing on my bike for Mt. Washington Hill climb. I was thinking of going with 34T ring with 11-40 cassette, Iam limited to 34t ring with existing crank sram force 1.
This would put me at 1 to 1 and then some lower gears for bail out. This is my 1st attempt at the Mt Washington hill climb, I am looking to complete under 90 minutes. Thank you in advance for every ones input. Water68.
I can't answer that question, but what I've read on this forum is that many people ride up Mt. Wachusett 6x times because it's the same elevation and similar gradients as Mt. Washington (not the downhill parts, of course). If you're in the area, you could try that and see what works.
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Old 02-27-20, 11:51 AM
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Mt. Washington Record Holders @ Welcome Mt. Washington Auto Road Bicycle Hillclimb. Check out the time records by age. That climb is an incredibly difficult one, the percent of gradient, the distance, the wind and the physical/mental fatigue are all part of the challenge. I do not think anyone can tell you what would be the best gearing for you. I do agree that just finishing the climb to the top is sufficient enough of a goal for the first attempt. I have seen some short takes on film of that ride. Definitely for strong riders.
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Old 02-27-20, 11:57 AM
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which hill climb ? The one I know of only goes to the tree line and not to the top.
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Old 02-27-20, 12:45 PM
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Originally Posted by PedalingWalrus View Post
which hill climb ? The one I know of only goes to the tree line and not to the top.
Look at the link in post 2, it's shows them at the parking lot on top.
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Old 02-27-20, 05:58 PM
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Thank You. Wow $350.
roughly $50 per mile :-) but I get it. It's one of a kind experience and basically the ONLY way to bike up that mountain road.



Originally Posted by Steve B. View Post
Look at the link in post 2, it's shows them at the parking lot on top.
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Old 02-27-20, 06:02 PM
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Awesome goal 👍

I say Single Speed it
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Old 02-28-20, 02:09 PM
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I've done Mt.Washington 3 times. All as a pure flatlander, no hill work worth mentioning done in advance. Show up and ride.

First time was on 42x28. That was nuts but I made the top in 1:26. Talked a bit to the second place finisher that day. He had also done it on 42x28 and said he could have raced for first if he had had a more reasonable gear.

Second time was on a low of 28x32 and also sick and feverish. 1:32 to the top. Bottom gear was only used for the final 27% ramp and was not necessary even there.

Third time there was a storm and the race was scrubbed. You do not get a refund. Instead did a lovely hike up Tuckerman Ravine on other side of mountain. The weather was sunny and beautiful. All the way up thinking we should have been allowed to race. Then sitting near top saw hikers in full expedition gear coming from other side of mountain looking like snowmen.

What you should expect is a ridiculously fast start. First half of mountain is steepest. A lot of tension is released as you leave the start line. If you are capable of a 1:30 finish you will hit halfway in 35-40 minutes, still in a big group. Halfway is also roughly the treeline. The road is almost flat for a hundred yards or so. Everyone backs off and tries to rest. Don't do it. The flat is just long enough so it will be crazy hard to regain any of the momentum that seemed so easy first half.

Forget pacing. Do not attempt to outsmart the mountain. Ride your bike. You are going to see all kinds of crazy rigs, all kinds of crazy strategy, most people finish. No one except top competitors who have done it many times before have the ride they expected.
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Old 02-28-20, 02:27 PM
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STRAVA: Mt. Washington, Gorham, NH

Whew, that is a pretty steady 12% climb, although minor details may be difficult to discern.

According the Strava, the top 20 riders or so barely hit it in 1 hour.

Gearing choice will certainly be rider dependent.

Put me on a 34/40 gear, and I would just crawl up the hill.

I'd probably select something more like 34/23 to 34/25. But I also realize the higher gearing works for shorter slopes, but may break down for long steady climbs.

I'd encourage you to set up your bike like you think you need it, then go out and find some 10% to 15% slopes near your home and just practice. See what works, what doesn't work. Even doing a few repeats on a 1/4 mile climb will tell you a lot.
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Old 02-28-20, 03:34 PM
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Originally Posted by 63rickert View Post
I've done Mt.Washington 3 times. All as a pure flatlander, no hill work worth mentioning done in advance. Show up and ride.

First time was on 42x28. That was nuts but I made the top in 1:26. Talked a bit to the second place finisher that day. He had also done it on 42x28 and said he could have raced for first if he had had a more reasonable gear.

Second time was on a low of 28x32 and also sick and feverish. 1:32 to the top. Bottom gear was only used for the final 27% ramp and was not necessary even there.

Third time there was a storm and the race was scrubbed. You do not get a refund. Instead did a lovely hike up Tuckerman Ravine on other side of mountain. The weather was sunny and beautiful. All the way up thinking we should have been allowed to race. Then sitting near top saw hikers in full expedition gear coming from other side of mountain looking like snowmen.

What you should expect is a ridiculously fast start. First half of mountain is steepest. A lot of tension is released as you leave the start line. If you are capable of a 1:30 finish you will hit halfway in 35-40 minutes, still in a big group. Halfway is also roughly the treeline. The road is almost flat for a hundred yards or so. Everyone backs off and tries to rest. Don't do it. The flat is just long enough so it will be crazy hard to regain any of the momentum that seemed so easy first half.

Forget pacing. Do not attempt to outsmart the mountain. Ride your bike. You are going to see all kinds of crazy rigs, all kinds of crazy strategy, most people finish. No one except top competitors who have done it many times before have the ride they expected.
The words of a guy who's been there. I climbed it twice, first as a tourist in 1975. (In those days, you paid the same toll drivers did and just rode. Up and down.) Didn't time it but probably a little over 90 minutes. Second time in the TT, 1978 where we started in groups of 3. Both times I rode a 28 x racing FW, 28 x 24 (I think) the first year, 28 x 21 the second time. Second time was 78 minutes. I'd hoped for better (and fully believe I could have hit 65 minutes the year before) but I had two strikes against me. The day before I rode a 113 mile 1,2 race I'd been upgraded to ride. Very windy! Over 5 hours. And this was my recovery year after my head injury. I never approached the form of my previous year. Had no legs at all and got off to walk twice. I felt like my gearing ws right. Just needed to start on fresh legs.

That last stretch is the hardest thing you will ever do on a bike. (A lot of people walk it.) I hit it and knew instantly that if I stopped, no way was I getting to the pulled tight toestraps before I fell over. Took everything I had to get to the parking lot. Then it was just a sea of people but I was oblivious. Deep oxygen dept and in post finish line mentality. Keep pedaling and slow gradually. Good thing I was in a tiny gear! That crowd grabbed me and pulled me to a stop before I ran out of parking lot. Lifted me off the bike and walked me into the lodge. (I was equally oblivious to the temperature in the mid-20s. I was dressed in tights and two jerseys, long sleeve and short.

I sent up additional clothing but carried almost nothing. Usual race stuff, cycling wallet, keys ... No food, water bottles or cages. Never crossed my mind to drink or that I even wanted too. Now, three years before I carried a lot more as I needed to be able to get myself off the mountain and maybe to survive.

I went up that mountain two other times. On the cog railway as a kid and hiked it 7th grade. I've had deep respect for the mountain since that hike. Our last night out was at the Lake of the Clouds AMC hut 1 1/2 miles from the summit. Our guide gave us the history of the hut when we arrived. After it was built but before it opened, they stocked a store shed with emergency supplies so any hiker caught out could use them. Across the "lake" (a small pond) was a cross. Dated December after the build and before the opening. So that hiker died not knowing food, clothing and fuel were 50 yards away, across a pond that was certainly frozen solid with maybe a foot of ice. There were no barriers to sight between the cross and the sign (except perhaps nightfall and a blizzard)..

Ben
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Old 02-29-20, 05:14 PM
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I've not ridden a bike up the mountain but I have hiked and backpacked a good bit in the area and on the mountain itself. You likely know already but mountains can generate their own weather. It would not be unheard of to have snow in mid summer. The temps at the summit are likely to be 15 or more degrees F colder at the summit than at the base. Many people misjudge the weather and as of a few years ago over 150 people had died on the mountain since it was first climbed. I would monitor weather carefully as the date of our adventure gets closer, especially so due to the no refund policy.
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Old 02-29-20, 06:14 PM
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+1 My second climb, when it was 20s at the top, we left in 50F at the tool booth.
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Old 03-02-20, 02:01 PM
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I rode it 2 1/2 times back in the '70's when it was open to the public. The half ride was due to a storm that rolled in just as we rode past the halfway hut. I was young and strong back then, and I could climb well in relatively big gears, so keep that in mind.
  • The first time was on my touring bike with a 38x28 low gear (Stronglight triple). The only problem I had was getting going again after stopping on the 5-Mile Grade (15%). It's not easy to get into toe clips on a steep grade with traffic going by, but I managed to do it by pushing off of a boulder. We rode down afterward and that was more painful than the climb.
  • The second time was during my racing years and I used a 42x28, because Campy cranks only went down to 42-tooth rings and the rear derailleur only handled up to 28 teeth, with some tweaking.
  • The third time, I built a special freewheel with 28,30 and 32-tooth cogs on the low end and the same 42 in the front. It seemed like it wasn't much easier and I just went slower in the lower gears, so I didn't use them much. This was the half ride, so I couldn't compare the overall experience.
Fast-forward to today and climbing steep grades in those kind of gears is a distant memory. Based on recent gravel rides and off-road riding with steep grades, I'd want something a bit lower than 1:1, which is what I have on my gravel bike (30x32). For that distance, it should be OK. I guess what I'm saying here is it all depends on your level of fitness and only you can gauge that.
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Old 03-02-20, 05:03 PM
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Figure out your maximum sustainable power output in Watts for 90 minutes. Multiply by 0.9 because when climbing about 10% of your energy goes into aerodynamic drag and rolling resistance.

In good shape I can manage 200W (what I measure averaging 20 MPH on "flat" ground) for 90 minutes * .9 = 180W climbing power.

Determine total mass of you and your bicycle. Multiply by 9.8 m/s^2 earth gravity for weight in newtons.

In good shape with shoes, clothing, water, and bike I total 73kg which is 715 newtons.

Divide your effective climbing power by weight in newtons to yield vertical ascent capability in meters per second. Multiply by 60 to yield meters per minute.


180 / 715 * 60 = 15.1 meters/minute

Convert the grade into a fraction dividing by 100. Divide into your meters per minute vertically to approximate road speed in the same units.

15.1 meters/minute / (12.1/100) = 125 meters per minute

Get wheel RPM dividing by wheel circumference in meters, where that's 3.14 * (bead seat diameter in mm + 2 * tire width in mm) / 1000

I ride 622x25mm tires with a circumference of 3.14 * .672 = 2.1 meters. 125 meters per minute / 2.1 = 60 RPM

Figure out the minimum cadence you can sustain seated. Divide that into your wheel RPM for your required gear ratio.

I can climb at 55 RPM. 60/55 = 1.09.

Divide that into your small ring tooth count to get cog size, or multiply by cog size to get the required ring.

I ride a triple so I can have tight gears for plains and low gears for mountains without changing cassettes.

With a 30 ring, I could ride a 30/1.09 = 28 cog.

With the 26 large cog I usually use, I could use a 26 * 1.09 = 28 small ring.

Ensure you also have a low enough gear for the switchbacks.

Determine what you need standing. 30 RPM is fine for me. Express it as a ratio to your seated cadence. Divide into cog and multiply by ring.

I can grind up things at 30 RPM. 55/30 = 1.8. 28/1.8 = a 16 cog, and 28 * 1.8 = 50 ring.

Adjust those by the difference between steep stops and average. They look to be under 20% except for 30% at the end, where you could exert yourself unsustainably.

20/12 = 1.7
30/12 = 2.5

16 * 1.7 = 27 cog; 50 / 1.7 = 29 ring.

I'd be OK with my regular climbing gear on the switch backs.

16 * 2.5 = 40 cog; 50 / 2.5 = 20 ring.

Divide by the setup you'd otherwise be using. 40/28 = 1.4

My regular climbing cog would work except at the end where I'd need 40% more power to keep the pedals turning over. That's OK for an overpass distance.

I'd probably use a 26 x 26.

Your mileage will vary.

Last edited by Drew Eckhardt; 03-02-20 at 08:30 PM.
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Old 03-03-20, 03:06 AM
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Originally Posted by Drew Eckhardt View Post
Figure out your maximum sustainable power output in Watts for 90 minutes blah blah blah MAths.
Kudos of figuring this out but OMG that is more effort for me as I am FAR to lazy and busy these days. I would take the easy way and just get a smart trainer and ride the GPX. I have done this to find out how challenging the hills are for the Eroica ride I am doing next month. BTW I have found I will be doing some walking. I think I will try this mountain on the trainer this weekend but I must say I didn't even like driving up it. LOL.
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Old 03-03-20, 05:52 AM
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Originally Posted by Drew Eckhardt View Post
Figure out your maximum sustainable power output in Watts for 90 minutes. Multiply by 0.9 because when climbing about 10% of your energy goes into aerodynamic drag and rolling resistance.

In good shape I can manage 200W (what I measure averaging 20 MPH on "flat" ground) for 90 minutes * .9 = 180W climbing power.

Determine total mass of you and your bicycle. Multiply by 9.8 m/s^2 earth gravity for weight in newtons.

In good shape with shoes, clothing, water, and bike I total 73kg which is 715 newtons.

Divide your effective climbing power by weight in newtons to yield vertical ascent capability in meters per second. Multiply by 60 to yield meters per minute.


180 / 715 * 60 = 15.1 meters/minute

Convert the grade into a fraction dividing by 100. Divide into your meters per minute vertically to approximate road speed in the same units.

15.1 meters/minute / (12.1/100) = 125 meters per minute

Get wheel RPM dividing by wheel circumference in meters, where that's 3.14 * (bead seat diameter in mm + 2 * tire width in mm) / 1000

I ride 622x25mm tires with a circumference of 3.14 * .672 = 2.1 meters. 125 meters per minute / 2.1 = 60 RPM

Figure out the minimum cadence you can sustain seated. Divide that into your wheel RPM for your required gear ratio.

I can climb at 55 RPM. 60/55 = 1.09.

Divide that into your small ring tooth count to get cog size, or multiply by cog size to get the required ring.

I ride a triple so I can have tight gears for plains and low gears for mountains without changing cassettes.

With a 30 ring, I could ride a 30/1.09 = 28 cog.

With the 26 large cog I usually use, I could use a 26 * 1.09 = 28 small ring.

Ensure you also have a low enough gear for the switchbacks.

Determine what you need standing. 30 RPM is fine for me. Express it as a ratio to your seated cadence. Divide into cog and multiply by ring.

I can grind up things at 30 RPM. 55/30 = 1.8. 28/1.8 = a 16 cog, and 28 * 1.8 = 50 ring.

Adjust those by the difference between steep stops and average. They look to be under 20% except for 30% at the end, where you could exert yourself unsustainably.

20/12 = 1.7
30/12 = 2.5

16 * 1.7 = 27 cog; 50 / 1.7 = 29 ring.

I'd be OK with my regular climbing gear on the switch backs.

16 * 2.5 = 40 cog; 50 / 2.5 = 20 ring.

Divide by the setup you'd otherwise be using. 40/28 = 1.4

My regular climbing cog would work except at the end where I'd need 40% more power to keep the pedals turning over. That's OK for an overpass distance.

I'd probably use a 26 x 26.

Your mileage will vary.
I tip my hat to this writer - his reply made my day. So meticulously precise that I couldn’t help but appreciate the information, and yet so precise that he made us remember that the information misses the point about riding. Thanks for it.
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Old 03-03-20, 08:38 AM
  #21  
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Cyclists do not produce constant power. Electric motors do that. Climbing makes power output more irregular. It's constant small accelerations and decelerations. Gravity is a constant. Gravity is never evaded. The smallest interruption to constant pedaling force means you slow down instantly. The slower the pedal rpm the larger the interruption.

Mt. Washington is a strange climb. Nothing constant about it. The roadway was not laid out by highway engineers. Made by a cheapskate private toll road and by the mountain itself. The road is all surprises.

It's a steep road and it suddenly gets steeper in or out of the switchback for no reason. It is very likely to be foggy, meaning no warning of what's hitting you next. In clear weather the sight lines are still all very short. Inertia does not carry you forward on this climb. More like you are continually re-starting from a standstill.

For imaginary calculations about climbing imaginary mountains better to figure what you need to never drop below 50 or 60 rpm. Note that in the extended calculations above that rider is traveling real slow. The object in top post was to get up mountain in 1:30. Also note there is 100 yards of easy on this mountain. All the rest is one big hill and it is steep. You are not shifting gears for the hard parts and the fast parts. It is all the hard part
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