Hill Climb Estimator

Last Update: 25-JUL-13

Northeast Hillclimbs Calculator Page
Disclaimer

These Java Script calculators can aid hillclimb cyclists in making correct gearing choices and in estimating climbing time. Most will obtain fairly accurate estimates, but a few could be way off. Remember, garbage in, garbage out. An estimator is only as good as the source data and assumptions it is based on. The models used here are simplistic, using a rolling/wind loss paramter that is average over several different climbs and riders. Use these calculators as scratch pads only, something to get you in the ballpark. Then go out and test your fitness, gearing, or whatever you are estimating on a climb. These calculators are no substitute for the real thing. Many thanks to Mike Bergstrom who provided the initial climb translator script to get me started with Java Script.

Mt Washington Time From Other Climbs

Select a climb, estimation method, and the time from which to estimate Mt Washington time, then click "Calculate". Estimation is based on actual race results over the last few years. The linear regression method may be more accurate for some comparisons. Based on sample data set, you have a 68% chance of falling within the standard deviation error shown below.

Climb:	Method:	Simple Mean Linear Regression
Time : :

Est. Mt Washington Time:
Time: : :
StdDev Error: min

Cadence Estimator

Select a climb, an estimated time for the climb, your nearest tire size from the list, and front chainring size. You can select one, two, or three cassette cog sizes with the percent time you think you spend in each cog. Only caveat is that your percents must sum to 100%. Not all climbs are available with this calculator. Only steep, mostly monotonic climbs are listed. Climbs that have large downhills, or extended flat sections will make estimating average cadence unreliable.

Climb:

Time: : : hrs:min:sec

Tire Size:
Chainring:
Cog 1:
Cog 2:
Cog 3:

Cadence: rpm

W/kg to Time Estimator

Select a climb, then enter estimated average power you can hold for the duration of the climb. Enter body weight, then the combined weight of bike and everything else. This includes bike, shoes, clothing, helmet, water bottle, spare tube, tools, pump, etc. Shoes with cleats alone can weight two pounds. Large water bottle with cage, another two pounds. Alternatively, if you wish to calculate power from your weight and a previous or anticipated finishing time, leave power blank, enter time and weight, then press calculate. Only steep, mostly monotonically rising climbs are estimated here. (More features being worked on)

Climb:

Power: Watts

Body Weight: lbs

Bike Weight: lbs (incl all misc wt)

Time: : : hrs:min:sec

Penalty per Pound: sec

Power Density: W/kg

Estimated Watts/kg from Climbing Time

Given one's climbing time, it is possible to estimate one's Watts/kilogram power output for a Mt Washington hillclimb. The chart below relies on several assumptions to estimate W/kg. These are:

Climbing time is based on fair conditions, that is, no extreme wind or mud
Bike, clothing, water, tools, etc all total 24 lbs (10.9kg)
Total losses (rolling, wind, etc) in climbing Mt Washington are 8%

A Top Notch time will require approx. 3.6W/kg or higher. If your bike and gear is much lighter than 24 lbs, maybe you'd be at 3.5W/kg. The blue curve below shows Watts per total climbing weight. This curve represents body weight plus 24 lbs. The red line is derived from it by applying power generated to body weight only. In good conditions, I have done the climb in 68 minutes a couple of times. This represents about 4.3W/kg for me. Just for kicks, Tom Danielson set the record at just under 50 minutes. This is about 5.7W/kg. His bike and gear were likely lighter than 24 lbs however, so he may have been closer to 5.5 or 5.6W/kg. I've read many reports of Lance Armstrong's power on various hills, typically around 6.5W/kg. This would put lance at around 45 minutes on Mt Washington. Per my calculations, Lance would have put out about 424W climbing Alpe d'Huez in the 2004 TdF TT (1125 meters vertical, 74kg + bike etc, 39.7 minutes). This is about 5.7W/kg, the same as Tom's on 10 minute longer Washington. BUT, Lance's d'Huez effort was well into the tour with more to go. Mt Washington is a one day affair for most that climb it, so you give it your all on fresh legs.

No Power Measurement?

So say you've never attempted Ascutney to estimate your Mt Washington time, and you do not have access to power measuring equipment. How do you estimate climbing time and gearing selection? Walter Zorn has one of the better speed and power calculators on his website at www.kreuzotter.de. What you can do, is ride a flat time-trial for a duration you think you can do Mt Washington in. Note your average speed. Then in Walter's calculator, enter your body specs, riding position, bike data, and your speed. It will calculate average power for you. It is important when you do this that wind (including beneficial draft from cars) is not a factor, and you ride alone. The terrain should be quite flat, and with no interruptions. This is typically very hard to do in New England, especially for 1-2 hours. You can also use Walter's calculator to directly estimate your Mt Washington climbing speed by entering a 12% grade. Then simply divide 7.6 miles by this calculated speed. But you will need a time-trial power estimate first, and this must come from you riding for 1-2+ hours at time-trial pace.

Perhaps the most robust online cycling calculator available is found at www.analyticcycling.com You can analyze to death any dynamic or static force on an part or your bike or body. The various tools here are not as easy to use, but the results are likely pretty accurate. You will need some knowledge of physics and aerodynamics to gain maximum use from this toolset. Lastly, Peter O'Reilly has also put together a Whiteface to Washington predictor based on several year's worth of data. This should be a little more robust than my predictor, which cherry picked data from one year with similar conditions for both races.