Hills and gearing: in one place all you need to know
12-01-04, 03:24 PM
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Hills and gearing: in one place all you need to know
My friends and I are event junkies all of a sudden. They want to do the death ride in the Ca. alps. I looked into it and it is a beast of a ride. Hills that kill.
I have a 39/52 set up right now with a 12-27 in the back. It does the job on most big hills less than 2 or so miles long, but after that the triple guys pass me and look like they have plenty of gas. So I looked into a triple, compact crank, or mnt rear derailleur and cassette.
The only real way to compare them is to talk in terms of what they give you per rotation.
As you pedal you move in inches per pedal. The more inches you push the faster you go at a set cadence. Conversely, less inches you push the slower you go at a set cadence.
You move more inches up front if you are on you large chain ring. You move more inches in back if you are on you smallest cog in the back. I get the feeling that most riders like the 52 up font on flats and like a 12-23 or 25 cassette in back.
For a hill, the less inches you push per pedal the easier it gets but you must compensate for the loss in inches per pedal by pedaling more…higher cadence. But it seems to me that hills tend to show the real range of abilities per rider and prompts a need for gear customization.
Let’s put it all here…all we know and have tried. I would recommend downloading a gear calculator and using inches for our chats. Free one at www.machinehead-software.co.uk
In the debate as what is best we should consider:
1) Gear spacing and continuity as it relates to cadence. (remeber the nine inch rule)
2) Versatility per terrain
3) Weight
4) Cost
5) What set up is best as the rider changes…stronger or weaker….
To start:
I think a compact crank is the best option. I came to the same conclusions of the following articles:
1) Compact cranks and gearing
4.28.04 by Simon Butterworth
(www.slowtwitch.com) = pure compact argument
2) SRAM Hollowpin chain and
PowerGlide II cassette
April 14, 2004, by Dan Empfield
(www.slowtwitch.com) = compact plus ATB set up in back.
In sum:
A 50/34 up front and a 11-23 in the back is best combination for most rides.
A 50,11 is more inch per pedal than the standard 52,12. A 34,23 is about the same as a 39,27 per inch.
A 11-23 has a close range and is lighter than a 12-27 and should be good for most rides.
For the hills simply swap out the 11-23 and put in the 12-27 and you got something like a triple set up at 30,23, but you lose top end speed capacity.
I’d like to hear from all of you and see what you think is best. By the way here is a chart set for 700c wheels. The middle collm. tell you inch and lets you compare what combos are alike. The last two collms. are a set rpm to show speed.
Front Rea Dia (inch) Min mph Max mph
70rpm 90rpm
39 11 93.32 20.54 24.99
39 12 85.54 18.83 22.9
39 13 78.96 17.38 21.14
39 14 73.32 16.14 19.63
39 15 68.43 15.07 18.32
39 16 64.16 14.12 17.18
39 17 60.38 13.29 16.17
39 18 57.03 12.55 15.27
39 19 54.03 11.89 14.47
39 20 51.32 11.3 13.74
39 21 48.88 10.76 13.09
39 22 46.66 10.27 12.49
39 23 44.63 9.83 11.95
39 24 42.77 9.42 11.45
39 25 41.06 9.04 10.99
39 26 39.48 8.69 10.57
39 27 38.02 8.37 10.18
39 28 36.66 8.07 9.82
39 29 35.4 7.79 9.48
39 30 34.22 7.53 9.16
52 11 124.42 27.39 33.31
52 12 114.05 25.11 30.54
52 13 105.28 23.18 28.19
52 14 97.76 21.52 26.18
52 15 91.24 20.09 24.43
52 16 85.54 18.83 22.9
52 17 80.51 17.72 21.56
52 18 76.04 16.74 20.36
52 19 72.03 15.86 19.29
52 20 68.43 15.07 18.32
52 21 65.17 14.35 17.45
52 22 62.21 13.7 16.66
52 23 59.51 13.1 15.93
52 24 57.03 12.55 15.27
52 25 54.75 12.05 14.66
52 26 52.64 11.59 14.09
52 27 50.69 11.16 13.57
52 28 48.88 10.76 13.09
52 29 47.19 10.39 12.64
52 30 45.62 10.04 12.22
34 11 81.35 17.91 21.78
34 12 74.57 16.42 19.97
34 13 68.84 15.15 18.43
34 14 63.92 14.07 17.11
34 15 59.66 13.13 15.97
34 16 55.93 12.31 14.98
34 17 52.64 11.59 14.09
34 18 49.72 10.94 13.31
34 19 47.1 10.37 12.61
34 20 44.74 9.85 11.98
34 21 42.61 9.38 11.41
34 22 40.68 8.95 10.89
34 23 38.91 8.57 10.42
34 24 37.29 8.21 9.98
34 25 35.8 7.88 9.58
34 26 34.42 7.58 9.22
34 27 33.14 7.3 8.87
34 28 31.96 7.04 8.56
34 29 30.86 6.79 8.26
34 30 29.83 6.57 7.99
34 32 27.97 5.82 7.49
50 11 119.64 26.34 32.03
50 12 109.67 24.14 29.36
50 13 101.23 22.29 27.1
50 14 94 20.69 25.17
50 15 87.73 19.31 23.49
50 16 82.25 18.11 22.02
50 17 77.41 17.04 20.73
50 18 73.11 16.1 19.58
50 19 69.26 15.25 18.55
50 20 65.8 14.49 17.62
50 21 62.67 13.8 16.78
50 22 59.82 13.17 16.02
50 23 57.22 12.6 15.32
50 24 54.83 12.07 14.68
50 25 52.64 11.59 14.09
50 26 50.62 11.14 13.55
50 27 48.74 10.73 13.05
50 28 47 10.35 12.58
50 29 45.38 9.99 12.15
50 30 43.87 9.66 11.75
50 32 41.13 8.56 11.01
30 11 71.78 14.95 19.22
30 12 65.8 13.7 17.62
30 13 60.74 12.65 16.26
30 14 56.4 11.75 15.1
30 15 52.64 10.96 14.09
30 16 49.35 10.28 13.21
30 17 46.45 9.67 12.44
30 18 43.87 9.14 11.75
30 19 41.56 8.65 11.13
30 20 39.48 8.22 10.57
30 21 37.6 7.83 10.07
30 22 35.89 7.47 9.61
30 23 34.33 7.15 9.19
30 24 32.9 6.85 8.81
30 25 31.58 6.58 8.46
30 26 30.37 6.32 8.13
30 27 29.24 6.09 7.83
30 28 28.2 5.87 7.55
30 29 27.23 5.67 7.29
30 30 26.32 5.48 7.05
I have a 39/52 set up right now with a 12-27 in the back. It does the job on most big hills less than 2 or so miles long, but after that the triple guys pass me and look like they have plenty of gas. So I looked into a triple, compact crank, or mnt rear derailleur and cassette.
The only real way to compare them is to talk in terms of what they give you per rotation.
As you pedal you move in inches per pedal. The more inches you push the faster you go at a set cadence. Conversely, less inches you push the slower you go at a set cadence.
You move more inches up front if you are on you large chain ring. You move more inches in back if you are on you smallest cog in the back. I get the feeling that most riders like the 52 up font on flats and like a 12-23 or 25 cassette in back.
For a hill, the less inches you push per pedal the easier it gets but you must compensate for the loss in inches per pedal by pedaling more…higher cadence. But it seems to me that hills tend to show the real range of abilities per rider and prompts a need for gear customization.
Let’s put it all here…all we know and have tried. I would recommend downloading a gear calculator and using inches for our chats. Free one at www.machinehead-software.co.uk
In the debate as what is best we should consider:
1) Gear spacing and continuity as it relates to cadence. (remeber the nine inch rule)
2) Versatility per terrain
3) Weight
4) Cost
5) What set up is best as the rider changes…stronger or weaker….
To start:
I think a compact crank is the best option. I came to the same conclusions of the following articles:
1) Compact cranks and gearing
4.28.04 by Simon Butterworth
(www.slowtwitch.com) = pure compact argument
2) SRAM Hollowpin chain and
PowerGlide II cassette
April 14, 2004, by Dan Empfield
(www.slowtwitch.com) = compact plus ATB set up in back.
In sum:
A 50/34 up front and a 11-23 in the back is best combination for most rides.
A 50,11 is more inch per pedal than the standard 52,12. A 34,23 is about the same as a 39,27 per inch.
A 11-23 has a close range and is lighter than a 12-27 and should be good for most rides.
For the hills simply swap out the 11-23 and put in the 12-27 and you got something like a triple set up at 30,23, but you lose top end speed capacity.
I’d like to hear from all of you and see what you think is best. By the way here is a chart set for 700c wheels. The middle collm. tell you inch and lets you compare what combos are alike. The last two collms. are a set rpm to show speed.
Front Rea Dia (inch) Min mph Max mph
70rpm 90rpm
39 11 93.32 20.54 24.99
39 12 85.54 18.83 22.9
39 13 78.96 17.38 21.14
39 14 73.32 16.14 19.63
39 15 68.43 15.07 18.32
39 16 64.16 14.12 17.18
39 17 60.38 13.29 16.17
39 18 57.03 12.55 15.27
39 19 54.03 11.89 14.47
39 20 51.32 11.3 13.74
39 21 48.88 10.76 13.09
39 22 46.66 10.27 12.49
39 23 44.63 9.83 11.95
39 24 42.77 9.42 11.45
39 25 41.06 9.04 10.99
39 26 39.48 8.69 10.57
39 27 38.02 8.37 10.18
39 28 36.66 8.07 9.82
39 29 35.4 7.79 9.48
39 30 34.22 7.53 9.16
52 11 124.42 27.39 33.31
52 12 114.05 25.11 30.54
52 13 105.28 23.18 28.19
52 14 97.76 21.52 26.18
52 15 91.24 20.09 24.43
52 16 85.54 18.83 22.9
52 17 80.51 17.72 21.56
52 18 76.04 16.74 20.36
52 19 72.03 15.86 19.29
52 20 68.43 15.07 18.32
52 21 65.17 14.35 17.45
52 22 62.21 13.7 16.66
52 23 59.51 13.1 15.93
52 24 57.03 12.55 15.27
52 25 54.75 12.05 14.66
52 26 52.64 11.59 14.09
52 27 50.69 11.16 13.57
52 28 48.88 10.76 13.09
52 29 47.19 10.39 12.64
52 30 45.62 10.04 12.22
34 11 81.35 17.91 21.78
34 12 74.57 16.42 19.97
34 13 68.84 15.15 18.43
34 14 63.92 14.07 17.11
34 15 59.66 13.13 15.97
34 16 55.93 12.31 14.98
34 17 52.64 11.59 14.09
34 18 49.72 10.94 13.31
34 19 47.1 10.37 12.61
34 20 44.74 9.85 11.98
34 21 42.61 9.38 11.41
34 22 40.68 8.95 10.89
34 23 38.91 8.57 10.42
34 24 37.29 8.21 9.98
34 25 35.8 7.88 9.58
34 26 34.42 7.58 9.22
34 27 33.14 7.3 8.87
34 28 31.96 7.04 8.56
34 29 30.86 6.79 8.26
34 30 29.83 6.57 7.99
34 32 27.97 5.82 7.49
50 11 119.64 26.34 32.03
50 12 109.67 24.14 29.36
50 13 101.23 22.29 27.1
50 14 94 20.69 25.17
50 15 87.73 19.31 23.49
50 16 82.25 18.11 22.02
50 17 77.41 17.04 20.73
50 18 73.11 16.1 19.58
50 19 69.26 15.25 18.55
50 20 65.8 14.49 17.62
50 21 62.67 13.8 16.78
50 22 59.82 13.17 16.02
50 23 57.22 12.6 15.32
50 24 54.83 12.07 14.68
50 25 52.64 11.59 14.09
50 26 50.62 11.14 13.55
50 27 48.74 10.73 13.05
50 28 47 10.35 12.58
50 29 45.38 9.99 12.15
50 30 43.87 9.66 11.75
50 32 41.13 8.56 11.01
30 11 71.78 14.95 19.22
30 12 65.8 13.7 17.62
30 13 60.74 12.65 16.26
30 14 56.4 11.75 15.1
30 15 52.64 10.96 14.09
30 16 49.35 10.28 13.21
30 17 46.45 9.67 12.44
30 18 43.87 9.14 11.75
30 19 41.56 8.65 11.13
30 20 39.48 8.22 10.57
30 21 37.6 7.83 10.07
30 22 35.89 7.47 9.61
30 23 34.33 7.15 9.19
30 24 32.9 6.85 8.81
30 25 31.58 6.58 8.46
30 26 30.37 6.32 8.13
30 27 29.24 6.09 7.83
30 28 28.2 5.87 7.55
30 29 27.23 5.67 7.29
30 30 26.32 5.48 7.05
12-01-04, 05:02 PM
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What about the loss of high gear with the compact crank? Getting up a hill is one thing, but I also pedal on the way down. I easily run out of gear with a 52-11 on the centuries that I do.
I like a triple myself. You get the low gears to spin up the long steep climbs. The middle chainring gives you a full range of usable gears. And you still have the big tall gears for descending. You get all of this out of one tightly spaced cassette.
I am not boohooing compact cranks, I am just curious why you are willing to give up a tall gear to get up the hill when you have to come down the other side. I guess, if you are just going up it makes sense. But, if you are going up AND down, you cripple yourself for half of your ride.
Plus, I would never tell a girl that I have a compact crank.
I like a triple myself. You get the low gears to spin up the long steep climbs. The middle chainring gives you a full range of usable gears. And you still have the big tall gears for descending. You get all of this out of one tightly spaced cassette.
I am not boohooing compact cranks, I am just curious why you are willing to give up a tall gear to get up the hill when you have to come down the other side. I guess, if you are just going up it makes sense. But, if you are going up AND down, you cripple yourself for half of your ride.
Plus, I would never tell a girl that I have a compact crank.
12-01-04, 06:47 PM
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Originally Posted by Avalanche325
...Plus, I would never tell a girl that I have a compact crank.
...you don't have to - such things are immediately apparent upon observation
12-01-04, 07:11 PM
#4
Senior Member
I've been flip-flopping with my decision for my next bike whether to go with a compact crank or a triple. The biggest factor swinging me either way is the crispness of shifting. When I've got my front derailleur tuned perfectly allowing me to use the full range of my cassette with no rubbing (on Sora shifters = no trimming) then I want a triple for my next bike knowing that things can only get easier with better shifters. When I just can't get the d@mn thing to shift properly or it rubs no matter what I do, then I want a compact double. I know I need the gears on the low end. It comes down to how much fun I want to have on the descent and shifting of course.
12-01-04, 07:53 PM
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I set up my salsa campeon for climbing with a compact crank. the lower gearing is not an issue since an 11 cog gets me the same as a 53x12. Spinning out a 52x11 is pretty impressive, how fast were you going? about 45 mph? I find that if I'm going that fast, I'm better off getting into a tight aero tuck. I also like the compact because I can stay in the big chainring on the flats and many small hills.
12-02-04, 12:10 PM
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Compact cranks and gearing
4.28.04 by Simon Butterworth
(www.slowtwitch.com)
Those old enough to remember the muscle cars of the 60’s will remember that at most they had 4-speed manual gears and, with automatics, there were only three. The engines in these cars could put out high torque and horsepower over a wide range of RPM. This made the need for more gears unnecessary.
Today’s high performance race car engines produce their maximum power in a narrow speed (RPM) range. To get the most power to the road the transmissions of these cars have closely spaced gears. They also have enough gears (5 and sometimes 6) to keep the engine turning over in the ideal RPM range up to their max speed. Human power output is a bit like a modern high performance engine, but with tiny amounts of power.
While some research suggests the most efficient cadence for cycling is in the 75 RPM range top cyclists typically maintain a cadence of 90-to 100 RPM. Slower cadences need more strength for one revolution and recruits more fast twitch muscle fibers. Conversely fewer fast twitch fibers are recruited at higher cadences. Since the fuel in our bodies used to fire the slow twitch fibers is much more abundant (fat) the endurance racer should ride around the 90 RPM range.
One of the changes Lance Armstrong made to his technique after recovering from cancer was to significantly increase his cadence. Watching him power up hills at 95 RPM is awesome and clearly effective. Tyler Hamilton also made the case for maintaining a high cadence in his breakaway stunning performance in stage-16 of last year’s Tour de France. He was using a “Compact” Crankset for this race. Here is a link to Tyler’s own account of the day. The rational for use of Compact cranks follows.
The conventional solution to maintain high cadence on a climb is to increase the size (number of teeth) of the large cog on the rear wheel. The smallest production cassette (on a 9 speed) has 11 teeth on the smallest cog and 21 on the largest (an 11-21 set). The next size up is an 11-23 which spreads the gears apart, not a desirable change. To get a 25-tooth cog gear manufacturers configure the set 12-25 and the next size up is 12-27 (other cassette manufacturers offer addition options, such as SRAM's 12-26).
The problem with a 12-27 cassette is the gears are spread apart even more than the 11-23 and you have lost some top speed potential. However, if you need the big cog to get up a hill you have no other choice. That is, until the Compact Crankset came on the market.
Compact cranks have chainrings that are significantly smaller than conventional cranks and are the polar opposite of the big chainrings seen so often on Tri Bikes. Compact cranks typically have 50/34 (sometimes 36) teeth on the outer and inner ring vs. 53/39 teeth on road bikes and 54/42 or bigger on Tri bikes. The ability to use these smaller chainrings occurs because of the crank's smaller bolt pattern, 110mm instead of the usual 130mm or 135mm spacing. There have been several articles about compact cranks in the Tri and Bicycling press in the past year. The argument put forward in these articles has been:
• Higher RPM’s can be maintained on steep climbs because of a lower low gear.
• Closer spacing of the gears makes it easer to maintain the optimal cadence as wind gusts and or small changes in elevation cause small speed changes.
• Some maximal speed potential on down hills is lost, but unless you are sustaining speeds of over 33mph on the flats this should not be an issue.
• The combination of Compact cranks and appropriate cassettes has less rotating mass (lighter) than a conventional set up.
None of the articles this author has seen quantified the difference between conventional Cranksets and the Compact Crankset. The following examines the speed differences between a 53-39 Chainring and a Compact (50-34) Chainring. The calculations are based on a 700c wheel with a cadence of 90 RPM. Bold print marks a change in cassette size.
...::: 700C Wheel At 90rpm :::...
53-39 Rings, 11-21 Cogs 50-34 Rings, 11-21 Cogset
High speed 33.2 MPH 31.3 MPH
Low speed 12.8 MPH 11.5 MPH
Comments Changes between each gear are the same (cssettes re the same). The tradeoff is easier climbing as the expense of a small loss of top speed. This s the lightest configuration for either set up.
53-39 Rings, 11-23 Cogs 50-34 Rings, 11-21 Cogset
High speed 33.2 MPH 31.3 MPH
Low speed 11.7 MPH 11.5 MPH
Comments Low speed now almost the same. 11-23 cassette is heaver with gear ratios wider apart.
53-39 Rings, 12-25 Cogs 50-34 Rings, 11-21 Cogset
High speed 30.42 MPH 31.3 MPH
Low speed 10.74 MPH 11.5 MPH
Comments The 12-25 cassette lowers the top speed on the conventional Crankset and makes climbing easier but at the cost of even wider gear ratios and weight.
53-39 Rings, 12-25 Cogs 50-34 Rings, 11-23 Cogset
High speed 30.42 MPH 31.3 MPH
Low speed 10.74 MPH 10.18 MPH
Comments With slightly wider gear ratios the 11-23 cogs further ease climbing with the Compact Crankset while maintaining top speed.
53-39 Rings, 12-27 Cogs 50-34 Rings, 11-23 Cogset
High speed 30.42 MPH 31.3 MPH
Low speed 9.98 MPH 10.18 MPH
Comments 12-27 is about the biggest (heaviest) cassette seen on Tri Bikes. Almost the same climbing can be achieved with the 11-23 cogs with a compact Crankset with a higher top speed, closer gearing and reduced weight.
It is easy to see why the Compact Crank would be a big plus for older age groups. So why would Tyler Hamilton choose Compact Cranks? Gear spacing and weight are probably the answer. Even on flat roads there is usually some variation in elevation and the wind is usually not constant. Closer gear spacing allows small changes in gearing, letting the elite rider to keep his cadence in a narrow ideal range.
Selecting optimal gearing for a bike needs consideration of the abilities of the athlete and the bike course (wind and hills). It is not unreasonable to have different gearing for different races. With conventional chain rings on a flat course an 11-21 cassette might be ideal. On a hilly course (Lake Placid IM) a 12-27 would be much better. With compact cranks you could use an 11-23 for both races with similar results. If you are an older or less powerful age grouper a 12-27 cassette with Compact cranks would eliminate the need for a triple Crankset (a heaver, more complicated solution sometimes used to get low gearing).
Compact-style cranks are available from FSA, Pinarello, Stronglight, Campagnolo and others. If you want to switch to smaller rings, because of the required 110mm bolt pattern, you can't just buy new chainrings. You must buy the whole crank.
*(Simon Butterworth is a USAT Level 1 coach and F.I.S.T. Certified Bike Fitter. He has completed 6 IronMan races, three in Hawaii and has achieved All American status in USAT ranking for the past 6 years. He can be reached at tricycle@optonline.net).
4.28.04 by Simon Butterworth
(www.slowtwitch.com)
Those old enough to remember the muscle cars of the 60’s will remember that at most they had 4-speed manual gears and, with automatics, there were only three. The engines in these cars could put out high torque and horsepower over a wide range of RPM. This made the need for more gears unnecessary.
Today’s high performance race car engines produce their maximum power in a narrow speed (RPM) range. To get the most power to the road the transmissions of these cars have closely spaced gears. They also have enough gears (5 and sometimes 6) to keep the engine turning over in the ideal RPM range up to their max speed. Human power output is a bit like a modern high performance engine, but with tiny amounts of power.
While some research suggests the most efficient cadence for cycling is in the 75 RPM range top cyclists typically maintain a cadence of 90-to 100 RPM. Slower cadences need more strength for one revolution and recruits more fast twitch muscle fibers. Conversely fewer fast twitch fibers are recruited at higher cadences. Since the fuel in our bodies used to fire the slow twitch fibers is much more abundant (fat) the endurance racer should ride around the 90 RPM range.
One of the changes Lance Armstrong made to his technique after recovering from cancer was to significantly increase his cadence. Watching him power up hills at 95 RPM is awesome and clearly effective. Tyler Hamilton also made the case for maintaining a high cadence in his breakaway stunning performance in stage-16 of last year’s Tour de France. He was using a “Compact” Crankset for this race. Here is a link to Tyler’s own account of the day. The rational for use of Compact cranks follows.
The conventional solution to maintain high cadence on a climb is to increase the size (number of teeth) of the large cog on the rear wheel. The smallest production cassette (on a 9 speed) has 11 teeth on the smallest cog and 21 on the largest (an 11-21 set). The next size up is an 11-23 which spreads the gears apart, not a desirable change. To get a 25-tooth cog gear manufacturers configure the set 12-25 and the next size up is 12-27 (other cassette manufacturers offer addition options, such as SRAM's 12-26).
The problem with a 12-27 cassette is the gears are spread apart even more than the 11-23 and you have lost some top speed potential. However, if you need the big cog to get up a hill you have no other choice. That is, until the Compact Crankset came on the market.
Compact cranks have chainrings that are significantly smaller than conventional cranks and are the polar opposite of the big chainrings seen so often on Tri Bikes. Compact cranks typically have 50/34 (sometimes 36) teeth on the outer and inner ring vs. 53/39 teeth on road bikes and 54/42 or bigger on Tri bikes. The ability to use these smaller chainrings occurs because of the crank's smaller bolt pattern, 110mm instead of the usual 130mm or 135mm spacing. There have been several articles about compact cranks in the Tri and Bicycling press in the past year. The argument put forward in these articles has been:
• Higher RPM’s can be maintained on steep climbs because of a lower low gear.
• Closer spacing of the gears makes it easer to maintain the optimal cadence as wind gusts and or small changes in elevation cause small speed changes.
• Some maximal speed potential on down hills is lost, but unless you are sustaining speeds of over 33mph on the flats this should not be an issue.
• The combination of Compact cranks and appropriate cassettes has less rotating mass (lighter) than a conventional set up.
None of the articles this author has seen quantified the difference between conventional Cranksets and the Compact Crankset. The following examines the speed differences between a 53-39 Chainring and a Compact (50-34) Chainring. The calculations are based on a 700c wheel with a cadence of 90 RPM. Bold print marks a change in cassette size.
...::: 700C Wheel At 90rpm :::...
53-39 Rings, 11-21 Cogs 50-34 Rings, 11-21 Cogset
High speed 33.2 MPH 31.3 MPH
Low speed 12.8 MPH 11.5 MPH
Comments Changes between each gear are the same (cssettes re the same). The tradeoff is easier climbing as the expense of a small loss of top speed. This s the lightest configuration for either set up.
53-39 Rings, 11-23 Cogs 50-34 Rings, 11-21 Cogset
High speed 33.2 MPH 31.3 MPH
Low speed 11.7 MPH 11.5 MPH
Comments Low speed now almost the same. 11-23 cassette is heaver with gear ratios wider apart.
53-39 Rings, 12-25 Cogs 50-34 Rings, 11-21 Cogset
High speed 30.42 MPH 31.3 MPH
Low speed 10.74 MPH 11.5 MPH
Comments The 12-25 cassette lowers the top speed on the conventional Crankset and makes climbing easier but at the cost of even wider gear ratios and weight.
53-39 Rings, 12-25 Cogs 50-34 Rings, 11-23 Cogset
High speed 30.42 MPH 31.3 MPH
Low speed 10.74 MPH 10.18 MPH
Comments With slightly wider gear ratios the 11-23 cogs further ease climbing with the Compact Crankset while maintaining top speed.
53-39 Rings, 12-27 Cogs 50-34 Rings, 11-23 Cogset
High speed 30.42 MPH 31.3 MPH
Low speed 9.98 MPH 10.18 MPH
Comments 12-27 is about the biggest (heaviest) cassette seen on Tri Bikes. Almost the same climbing can be achieved with the 11-23 cogs with a compact Crankset with a higher top speed, closer gearing and reduced weight.
It is easy to see why the Compact Crank would be a big plus for older age groups. So why would Tyler Hamilton choose Compact Cranks? Gear spacing and weight are probably the answer. Even on flat roads there is usually some variation in elevation and the wind is usually not constant. Closer gear spacing allows small changes in gearing, letting the elite rider to keep his cadence in a narrow ideal range.
Selecting optimal gearing for a bike needs consideration of the abilities of the athlete and the bike course (wind and hills). It is not unreasonable to have different gearing for different races. With conventional chain rings on a flat course an 11-21 cassette might be ideal. On a hilly course (Lake Placid IM) a 12-27 would be much better. With compact cranks you could use an 11-23 for both races with similar results. If you are an older or less powerful age grouper a 12-27 cassette with Compact cranks would eliminate the need for a triple Crankset (a heaver, more complicated solution sometimes used to get low gearing).
Compact-style cranks are available from FSA, Pinarello, Stronglight, Campagnolo and others. If you want to switch to smaller rings, because of the required 110mm bolt pattern, you can't just buy new chainrings. You must buy the whole crank.
*(Simon Butterworth is a USAT Level 1 coach and F.I.S.T. Certified Bike Fitter. He has completed 6 IronMan races, three in Hawaii and has achieved All American status in USAT ranking for the past 6 years. He can be reached at tricycle@optonline.net).
12-02-04, 12:41 PM
#7
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Like the table shows and the art. above tells you is that you only lose a small amount of top speed. Plus, most bikes come of the line with a 12tooth at the first position. Thus, the 11-23 plus the compact's 50 will be a bit faster than most bikes.
Also, the cost of a triple set up from a doulbe is way more costly. FSA energy is about 120.00 us. The shifting is clean and the 9 inch rule is not broken for the most part.
Last, I'd like to ride with ego if it made me faster or climb. I’m sure that Tyler Hamilton did not mind that a girl could see that he was on a compact and that he could kick ass with it. Or you could ask how many were on a triple on the last tour.
If your really about the ego of the ride stay on old school steel, go back to 5 speed, down tube shifters, and a wool jersey. Unless your running a constant 33 mph on flats, I’m sure the girls will notice that old school set up as they pass you by.
Also, the cost of a triple set up from a doulbe is way more costly. FSA energy is about 120.00 us. The shifting is clean and the 9 inch rule is not broken for the most part.
Last, I'd like to ride with ego if it made me faster or climb. I’m sure that Tyler Hamilton did not mind that a girl could see that he was on a compact and that he could kick ass with it. Or you could ask how many were on a triple on the last tour.
If your really about the ego of the ride stay on old school steel, go back to 5 speed, down tube shifters, and a wool jersey. Unless your running a constant 33 mph on flats, I’m sure the girls will notice that old school set up as they pass you by.
12-02-04, 01:38 PM
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Those old enough to remember the muscle cars of the 60’s will remember that at most they had 4-speed manual gears and, with automatics, there were only three. The engines in these cars could put out high torque and horsepower over a wide range of RPM. This made the need for more gears unnecessary.
Today’s high performance race car engines produce their maximum power in a narrow speed (RPM) range. To get the most power to the road the transmissions of these cars have closely spaced gears. They also have enough gears (5 and sometimes 6) to keep the engine turning over in the ideal RPM range up to their max speed. Human power output is a bit like a modern high performance engine, but with tiny amounts of power.
Today’s high performance race car engines produce their maximum power in a narrow speed (RPM) range. To get the most power to the road the transmissions of these cars have closely spaced gears. They also have enough gears (5 and sometimes 6) to keep the engine turning over in the ideal RPM range up to their max speed. Human power output is a bit like a modern high performance engine, but with tiny amounts of power.
Also a muscle car is not a race car. Lets compare a 60s muscle car to something comperable, let's say a Corvette Z06 or a Mercedes E55 (full sized).
Both of these cars have more power and more torque than a Hemi Cuda, 427 Cobra, or a 427 Corvette. They also have broader HP and torque ranges. They also have more gears. And they are also faster.
I know that wasn't the point. But it is a bad analogy.
12-02-04, 02:57 PM
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If you spent less time worrying about what gear you have and more time training on the hills... you would not need this crap
12-02-04, 11:43 PM
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Training on the hills is not the topic. If I wanted a training pep talk I would have asked for one. No sh>>>>> training will help you on a hill but so will smart gear choice
do you have anything helpful or intelligent to add or is THAT NOT YOUR thing?
do you have anything helpful or intelligent to add or is THAT NOT YOUR thing?
12-03-04, 08:09 AM
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Originally Posted by ggg300
Training on the hills is not the topic. If I wanted a training pep talk I would have asked for one. No sh>>>>> training will help you on a hill but so will smart gear choice
do you have anything helpful or intelligent to add or is THAT NOT YOUR thing?
do you have anything helpful or intelligent to add or is THAT NOT YOUR thing?
12-03-04, 10:27 AM
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Hay look what I found.....it must be the bike? What about training**********?
"Well people, I am here to tell you that I learned a leason. I had always been a believer that the bike you were riding made very little difference in how fast you can go....
Last night, I did our local Wednesday night ride that leaves Oregon Ridge park in northern Baltimore County, MD at 6 PM for 31 miles of mayhem. Unfortunately for me, I had sheered off the one chainring bolt on my Record crank that holds the rings to the spider the day before and was awaiting a replacement in the mail. So, instead of riding my 2001 Look KG241 I was stuck with my beater - a 1986 Gatane Performace, 24lbs of Columbus steel with downtube shifters. I had not riden the Gatane in over a year.... what a truck! And to think, I used to race on that thing. Well, the pace was blistering right out of the gate and I got relagated to the second group in no time. The Gatane was OK once you got it going, but it would not accelerate.
I would rather ride the Gatane than not ride at all... but man I missed my plastic fantastic...."
"Well people, I am here to tell you that I learned a leason. I had always been a believer that the bike you were riding made very little difference in how fast you can go....
Last night, I did our local Wednesday night ride that leaves Oregon Ridge park in northern Baltimore County, MD at 6 PM for 31 miles of mayhem. Unfortunately for me, I had sheered off the one chainring bolt on my Record crank that holds the rings to the spider the day before and was awaiting a replacement in the mail. So, instead of riding my 2001 Look KG241 I was stuck with my beater - a 1986 Gatane Performace, 24lbs of Columbus steel with downtube shifters. I had not riden the Gatane in over a year.... what a truck! And to think, I used to race on that thing. Well, the pace was blistering right out of the gate and I got relagated to the second group in no time. The Gatane was OK once you got it going, but it would not accelerate.
I would rather ride the Gatane than not ride at all... but man I missed my plastic fantastic...."
12-03-04, 10:44 AM
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Originally Posted by ggg300
want to do the death ride in the Ca. alps. I looked into it and it is a beast of a ride. Hills that kill.
While we're on this big-climbing topic ... anybody climbed Haleakala (Maui)? From Paia Town (sea level) to the summit, 38 miles from sea level to just over 10,000? Was there for summer last year and saw some guys doing it. Wow.
12-05-04, 09:39 PM
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I was introduced to this bike thing by an older guy who was known as “Speedy.” (corny…I know….) He’d kick ass especially on the hills. He is getting older and has now moved to a triple, and when I ride with him I hate to pass him. I almost feel it is disrespectful.
In his prime he ran a 53 up top and a 11-21 in the back and he would fly. He also had a lot of the macho bravado like so many guys I see on rides. I could tell that the move to a triple was almost shameful to him.
The last event ride we did was his worst ever. On training rides he’d leave before us and when we caught him I could see that he was punishing himself. He would resist the “half step + granny.” I would think to myself….there goes that dam pride.
More and more he would complain about his age and after the last event ride he told the group that it was his last one. Over a few beers I tried to talk him out of it. I told him that maybe he needed to change things and modify all kinds of stuff. He did not seem to care much about what I was saying. His point of reference was that 53-11.
I looked up to this old buck for the longest until that night. It was macho pride that robbed the guy of what I think riding is about.
Riding is part mechanical, mental, preparation, and heart. We ride machines. We have brains. We can recognize our abilities and modify our machines accordingly. That is the point. If we rode with as much brains as we do heart….man we can ride a lot farther, faster, and longer.
To me macho pride is a weakness not a strength. It has crippled the guy who brought me into this bike thing. Thinking is not worrying, and I think about gearing as much as training.
That is the point. Bikes like Gearing make a difference.
In his prime he ran a 53 up top and a 11-21 in the back and he would fly. He also had a lot of the macho bravado like so many guys I see on rides. I could tell that the move to a triple was almost shameful to him.
The last event ride we did was his worst ever. On training rides he’d leave before us and when we caught him I could see that he was punishing himself. He would resist the “half step + granny.” I would think to myself….there goes that dam pride.
More and more he would complain about his age and after the last event ride he told the group that it was his last one. Over a few beers I tried to talk him out of it. I told him that maybe he needed to change things and modify all kinds of stuff. He did not seem to care much about what I was saying. His point of reference was that 53-11.
I looked up to this old buck for the longest until that night. It was macho pride that robbed the guy of what I think riding is about.
Riding is part mechanical, mental, preparation, and heart. We ride machines. We have brains. We can recognize our abilities and modify our machines accordingly. That is the point. If we rode with as much brains as we do heart….man we can ride a lot farther, faster, and longer.
To me macho pride is a weakness not a strength. It has crippled the guy who brought me into this bike thing. Thinking is not worrying, and I think about gearing as much as training.
That is the point. Bikes like Gearing make a difference.
