School me on tooth difference in performance
#1
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Quidam Bike Super Hero
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From: Stone Mountain, GA (Metro Atlanta, East)
Bikes: 1995 Trek 800 Sport, aka, "CamelTrek"
School me on tooth difference in performance
Just replaced a triple ring 28/38/48 with a triple 22/32/42.... Haven't put my bike through the paces yet. What can I expect and why? Make the explanation as semi-technical as you like... I enjoy learning new things, especially on my bike!
#3
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☝️ I agree!
Every time you pedal a circle you move the bike ‘X’ teeth. So with your new gearing you will move the bike fewer ‘teeth’ than with your former chain ring. Now, of course, that also depends on your cassette, but since you don’t say you have changed that it should be irrelevant.
If the gear on you are using on your cassette has 24 teeth then with every cycle the old chain ring (large gear) would rotate the tires 48/24 or 2Xs. The new one will rotate the tires 42/24 or 1.75Xs. Less distance equals less effort.
Every time you pedal a circle you move the bike ‘X’ teeth. So with your new gearing you will move the bike fewer ‘teeth’ than with your former chain ring. Now, of course, that also depends on your cassette, but since you don’t say you have changed that it should be irrelevant.
If the gear on you are using on your cassette has 24 teeth then with every cycle the old chain ring (large gear) would rotate the tires 48/24 or 2Xs. The new one will rotate the tires 42/24 or 1.75Xs. Less distance equals less effort.
#4
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It will easier to pedal up hills, but on flat roads you will go slower with similar effort.
#7
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Quidam Bike Super Hero
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From: Stone Mountain, GA (Metro Atlanta, East)
Bikes: 1995 Trek 800 Sport, aka, "CamelTrek"
#9
You'll have easier gearing for going up hills in the small chainring, but assuming the same rear cassette (gearing), you will have to spin very quickly to make the bike go the same speed in the big chainring.
I enjoy numbers, and there are a few gear calculators that can give you additional data using chainring and cassette sizes. First, this one (https://www.bikecalc.com) gives you a bunch of information, including the useful speed at cadence, or how fast the bike will go given the RPM of your pedaling. Green combinations are faster/harder to pedal; red combinations are slower/easier to pedal.
There's also the Sheldon Brown gear calculator (https://www.sheldonbrown.com/gear-calc.html) which provides the very interesting meters of development - how far your bike will travel forward with each rotation of the pedals. You can do some math and, for example, calculate how many times you'll need to turn the pedals per mile in each gear. This is probably useful only if you're on long solo rides and need something to focus on while passing the time.
I enjoy numbers, and there are a few gear calculators that can give you additional data using chainring and cassette sizes. First, this one (https://www.bikecalc.com) gives you a bunch of information, including the useful speed at cadence, or how fast the bike will go given the RPM of your pedaling. Green combinations are faster/harder to pedal; red combinations are slower/easier to pedal.
There's also the Sheldon Brown gear calculator (https://www.sheldonbrown.com/gear-calc.html) which provides the very interesting meters of development - how far your bike will travel forward with each rotation of the pedals. You can do some math and, for example, calculate how many times you'll need to turn the pedals per mile in each gear. This is probably useful only if you're on long solo rides and need something to focus on while passing the time.
#10
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.
#12
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#14
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If you had difficulty climbing up some of the hills in your area with your previous crankset, you are going to have less difficulty climbing up the hills with your new one.
If you found yourself running out of gears and freewheeling on the downhills previously, you are going to run out of gears and find yourself freewheeling even sooner with your new crankset.
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#15
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#19
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From: Stone Mountain, GA (Metro Atlanta, East)
Bikes: 1995 Trek 800 Sport, aka, "CamelTrek"
Maybe no performance difference at all, particularly if you ride mostly flat roads.
If you had difficulty climbing up some of the hills in your area with your previous crankset, you are going to have less difficulty climbing up the hills with your new one.
If you found yourself running out of gears and freewheeling on the downhills previously, you are going to run out of gears and find yourself freewheeling even sooner with your new crankset.
If you had difficulty climbing up some of the hills in your area with your previous crankset, you are going to have less difficulty climbing up the hills with your new one.
If you found yourself running out of gears and freewheeling on the downhills previously, you are going to run out of gears and find yourself freewheeling even sooner with your new crankset.
#20
Thread Starter
Quidam Bike Super Hero
Joined: Jan 2019
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From: Stone Mountain, GA (Metro Atlanta, East)
Bikes: 1995 Trek 800 Sport, aka, "CamelTrek"
You'll have easier gearing for going up hills in the small chainring, but assuming the same rear cassette (gearing), you will have to spin very quickly to make the bike go the same speed in the big chainring.
I enjoy numbers, and there are a few gear calculators that can give you additional data using chainring and cassette sizes. First, this one (https://www.bikecalc.com) gives you a bunch of information, including the useful speed at cadence, or how fast the bike will go given the RPM of your pedaling. Green combinations are faster/harder to pedal; red combinations are slower/easier to pedal.
There's also the Sheldon Brown gear calculator (https://www.sheldonbrown.com/gear-calc.html) which provides the very interesting meters of development - how far your bike will travel forward with each rotation of the pedals. You can do some math and, for example, calculate how many times you'll need to turn the pedals per mile in each gear. This is probably useful only if you're on long solo rides and need something to focus on while passing the time.
I enjoy numbers, and there are a few gear calculators that can give you additional data using chainring and cassette sizes. First, this one (https://www.bikecalc.com) gives you a bunch of information, including the useful speed at cadence, or how fast the bike will go given the RPM of your pedaling. Green combinations are faster/harder to pedal; red combinations are slower/easier to pedal.
There's also the Sheldon Brown gear calculator (https://www.sheldonbrown.com/gear-calc.html) which provides the very interesting meters of development - how far your bike will travel forward with each rotation of the pedals. You can do some math and, for example, calculate how many times you'll need to turn the pedals per mile in each gear. This is probably useful only if you're on long solo rides and need something to focus on while passing the time.
#21
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Quidam Bike Super Hero
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From: Stone Mountain, GA (Metro Atlanta, East)
Bikes: 1995 Trek 800 Sport, aka, "CamelTrek"
#22
Thread Starter
Quidam Bike Super Hero
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From: Stone Mountain, GA (Metro Atlanta, East)
Bikes: 1995 Trek 800 Sport, aka, "CamelTrek"
#23
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Quidam Bike Super Hero
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From: Stone Mountain, GA (Metro Atlanta, East)
Bikes: 1995 Trek 800 Sport, aka, "CamelTrek"
#24
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#25
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From: St Peters, Missouri
Bikes: Catrike 559 I own some others but they don't get ridden very much.








