Tooth Count?
#4
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From: Brooklyn, NY, USA
Bikes: mid-80's Bianchi, converted to single speed, purple
1. could you please explain what that means?
2. what do you use?
I'm going to buy a new chainring. My current one is 50+. The rear cog is 16 tooth. New bike, have only had it for a week, and I'm new to biking in general. Any help is appreciated.
2. what do you use?
I'm going to buy a new chainring. My current one is 50+. The rear cog is 16 tooth. New bike, have only had it for a week, and I'm new to biking in general. Any help is appreciated.
#5
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What kind of tooth count...?
#11
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From: Brooklyn, NY, USA
Bikes: mid-80's Bianchi, converted to single speed, purple
#12
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From: Chico, CA
Bikes: Colnago C59 Italia, 1981 Bianchi Pista
Gear-trains are incredibly simple, so I'm going to try to explain them briefly.
If your ratio is 48/16, for instance, it can be simplified to 3/1. That means that for every revolution of the cranks, the wheel does three revolutions. A 45/15 ratio would produce an identical result in terms of pedaling effort required. A ratio of, say, 40/16 means that for every revolution of the cranks, the wheel does two and a half revolutions. It becomes easier to pedal, since the effort you put in is not moving you forward as far. When you're going down a hill, however, this becomes a bad thing, since your cranks will be turning more for each wheel revolution.
If your ratio is 48/16, for instance, it can be simplified to 3/1. That means that for every revolution of the cranks, the wheel does three revolutions. A 45/15 ratio would produce an identical result in terms of pedaling effort required. A ratio of, say, 40/16 means that for every revolution of the cranks, the wheel does two and a half revolutions. It becomes easier to pedal, since the effort you put in is not moving you forward as far. When you're going down a hill, however, this becomes a bad thing, since your cranks will be turning more for each wheel revolution.
#14
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From: Brooklyn, NY, USA
Bikes: mid-80's Bianchi, converted to single speed, purple
Gear-trains are incredibly simple, so I'm going to try to explain them briefly.
If your ratio is 48/16, for instance, it can be simplified to 3/1. That means that for every revolution of the cranks, the wheel does three revolutions. A 45/15 ratio would produce an identical result in terms of pedaling effort required. A ratio of, say, 40/16 means that for every revolution of the cranks, the wheel does two and a half revolutions. It becomes easier to pedal, since the effort you put in is not moving you forward as far. When you're going down a hill, however, this becomes a bad thing, since your cranks will be turning more for each wheel revolution.
If your ratio is 48/16, for instance, it can be simplified to 3/1. That means that for every revolution of the cranks, the wheel does three revolutions. A 45/15 ratio would produce an identical result in terms of pedaling effort required. A ratio of, say, 40/16 means that for every revolution of the cranks, the wheel does two and a half revolutions. It becomes easier to pedal, since the effort you put in is not moving you forward as far. When you're going down a hill, however, this becomes a bad thing, since your cranks will be turning more for each wheel revolution.
couple more questions:
- What is the average or standard or recommended gear ratio for a single speed?
- On the wikipedia page for bicycle gearing (https://en.wikipedia.org/wiki/Bicycle_gearing) it gives some examples. For shorter rides (up to 5 miles) use a gear around 60. How does that gear number relate to the gear ratio?
- Regarding the issue of a lower gear ratio complicating going down hills, is that really an issue with a single speed? Or is that more of a fixed gear problem?
thanks again for the help.
#15
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From: Brooklyn, NY, USA
Bikes: mid-80's Bianchi, converted to single speed, purple
Just found this thread with the chart:
https://www.bikeforums.net/singlespeed-fixed-gear/468351-gearing-primer.html
Does this mean if I have a 27 inch tire, with a 16 tooth rear cog, that I want a chainring with a tooth count around 39-47 (which would put my gear in the "road use green." with 39 tooth putting me at 65.8 and 47 tooyh putting me at 79.3?
Sixty Fiver says he likes to be in the 65-70 range for his SS, so that would my preferred chainring tooth count at 39-42?
https://www.bikeforums.net/singlespeed-fixed-gear/468351-gearing-primer.html
Does this mean if I have a 27 inch tire, with a 16 tooth rear cog, that I want a chainring with a tooth count around 39-47 (which would put my gear in the "road use green." with 39 tooth putting me at 65.8 and 47 tooyh putting me at 79.3?
Sixty Fiver says he likes to be in the 65-70 range for his SS, so that would my preferred chainring tooth count at 39-42?
#16
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From: Ciudad de Vacas, Tejas
Bikes: 34 frames + 80 wheels
Typical single speeds like the Trek Soho S have a gear ratio of 2.6 (44 x17), which works out to 70 gear inches for a 27 inch diameter tire. My SS, which is a conversion of an old Mercier 10-speed from the early 1970's has a 52 x 20, which works out to a 2.6 gear ratio.
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Thank you.
couple more questions:
- What is the average or standard or recommended gear ratio for a single speed?
- On the wikipedia page for bicycle gearing (https://en.wikipedia.org/wiki/Bicycle_gearing) it gives some examples. For shorter rides (up to 5 miles) use a gear around 60. How does that gear number relate to the gear ratio?
- Regarding the issue of a lower gear ratio complicating going down hills, is that really an issue with a single speed? Or is that more of a fixed gear problem?
thanks again for the help.
couple more questions:
- What is the average or standard or recommended gear ratio for a single speed?
- On the wikipedia page for bicycle gearing (https://en.wikipedia.org/wiki/Bicycle_gearing) it gives some examples. For shorter rides (up to 5 miles) use a gear around 60. How does that gear number relate to the gear ratio?
- Regarding the issue of a lower gear ratio complicating going down hills, is that really an issue with a single speed? Or is that more of a fixed gear problem?
thanks again for the help.
So 44/16 is a kind of common. Again, it depends on how much hill you have to climb and how strong you are.
Too low of a ratio is not that much of an issue for singlespeed since you can coast down hill.
Gear inches = diameter of the tire (in inches) times the number of tooth on your chain ring divided by your number of tooth of your cog.
For example, a person with a 700x23c wheel running a gear ratio of 44/16 will have a gear inches of 72.3
You can do it with a common calculator if you know the diameter of your tire.
700x23c tires are 26.275
700x25c tires are 26.375
700x28c tires are 26.75
then you pick whichever tire size
26.275x44 = 1156.1
then divided it by 16
1156.1/16= 72.25625...round it off to the nearest tenth.
72.3 gear inches.
I also posted a calculator on your other post, here it is again
https://software.bareknucklebrigade.c...it.applet.html
#18
Just found this thread with the chart:
https://www.bikeforums.net/showthread.php?t=468351
Sixty Fiver says he likes to be in the 65-70 range for his SS, so that would my preferred chainring tooth count at 39-42?
https://www.bikeforums.net/showthread.php?t=468351
Sixty Fiver says he likes to be in the 65-70 range for his SS, so that would my preferred chainring tooth count at 39-42?
#20
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From: Brooklyn, NY, USA
Bikes: mid-80's Bianchi, converted to single speed, purple
f50fan.
I'm in brooklyn. Not many steep hills, but some inclines. Also, doesn't seem like there is a ton of all out speed riding as there are the stop lights and other traffic issues. I'm in my early 30's, and not in the best shape (although I am changing that with this bike!)
Just to follow up.
So I have a 27 inch wheel
16 tooth rear cog
54 tooth chainring
puts my gear inches at at 91.1 and gear ratio at 3.37:1
That's a little ridiculous for a single speed? The guy who I bought the bike from must have been a monster!
I'm in brooklyn. Not many steep hills, but some inclines. Also, doesn't seem like there is a ton of all out speed riding as there are the stop lights and other traffic issues. I'm in my early 30's, and not in the best shape (although I am changing that with this bike!)
Just to follow up.
So I have a 27 inch wheel
16 tooth rear cog
54 tooth chainring
puts my gear inches at at 91.1 and gear ratio at 3.37:1
That's a little ridiculous for a single speed? The guy who I bought the bike from must have been a monster!
#21
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From: Ciudad de Vacas, Tejas
Bikes: 34 frames + 80 wheels
#23
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I'd probably agree with this. I used to run 42 x 16 and just recently switched to 46 x 17 to get more skid patches, with only a slight increase in gear inches. But then again, I was running fixed and skidding easily was part of the reason I liked that ratio.
For fixed, this ratio would probably be good, but I think if you were running a freewheel you could stand to up the gear inches a bit.
For fixed, this ratio would probably be good, but I think if you were running a freewheel you could stand to up the gear inches a bit.
#25
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From: Brooklyn, NY, USA
Bikes: mid-80's Bianchi, converted to single speed, purple
I don't do a lot of climbs, more slight elevation increases.



