50/19 gear ratio
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50/19 gear ratio
I just bought a used fixie and it has a 50t crank and 19t on the axle. I’m trying to figure the ratio and if I should change it. I live in a hilly area and most hills I can climb with some effort but I can climb them. I can’t do a skid stop but it does have 700x45c xc tires on it right now. I have some 700x23c laying around I’m going to see if they will fit tomorrow. Can anyone tell me the gear ratio or if I would be better with a 44/16
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The ratio of 50t/19t is 2.63 while the 44t/16t ratio is 2.75, i.e. slightly higher. So it would be a little harder to climb hills with the 44t & 16t gears. If you want to make it easier to climb steep hills then either swap the 50t ring for one with fewer teeth or use a cog with more than 19 teeth.
Last edited by prathmann; 11-10-18 at 08:16 PM.
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It will definitely be easier to push with skinnier tires. I'd go for 25s over 23s but if you already have them laying around, might as well.
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Your effective gear needs to take into account chainring teeth, sprocket teeth, wheel diameter and, theoretically, crank length — although bicyclists usually use a fairly standard crank length.
The wheel diameter can be ignored only if you are certain that everyone is talking about the same diameter wheels. When 700c was universal, this was OK. Now that 29 inch, 26 inch and 650b wheel sizes are also common it has become more important.
The calculation is
Chain ring teeth, divided by sprocket teeth, multiplied by wheel diameter in inches.
That gives you a gear size in "inches" which is the theoretical equivalent size of the front wheel if you were riding an "ordinary bike" which is what they used to call penny farthings. Ordinaries had direct drive with no gearing, and the gear inches idea was to enable people to compare the later "safety bicycles' (the earliest bikes we would recognise as "bikes") with ordinaries.
So, 50/19 x 28 would produce a gear of 73.7 inches. (A 700c road tyre is roughly 28 inches diameter.)
For comparison, I ride 49/20 or 49/18 giving me choices of 68.6 or 76.2 inches. I'm 55 and not as fit as I was and I can ride either of these comfortably on rolling country lanes and up all of our local hills, such as they are. Your gear sounds "not unreasonable".
The wheel diameter can be ignored only if you are certain that everyone is talking about the same diameter wheels. When 700c was universal, this was OK. Now that 29 inch, 26 inch and 650b wheel sizes are also common it has become more important.
The calculation is
Chain ring teeth, divided by sprocket teeth, multiplied by wheel diameter in inches.
That gives you a gear size in "inches" which is the theoretical equivalent size of the front wheel if you were riding an "ordinary bike" which is what they used to call penny farthings. Ordinaries had direct drive with no gearing, and the gear inches idea was to enable people to compare the later "safety bicycles' (the earliest bikes we would recognise as "bikes") with ordinaries.
So, 50/19 x 28 would produce a gear of 73.7 inches. (A 700c road tyre is roughly 28 inches diameter.)
For comparison, I ride 49/20 or 49/18 giving me choices of 68.6 or 76.2 inches. I'm 55 and not as fit as I was and I can ride either of these comfortably on rolling country lanes and up all of our local hills, such as they are. Your gear sounds "not unreasonable".
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Your effective gear needs to take into account chainring teeth, sprocket teeth, wheel diameter and, theoretically, crank length — although bicyclists usually use a fairly standard crank length.
The wheel diameter can be ignored only if you are certain that everyone is talking about the same diameter wheels. When 700c was universal, this was OK. Now that 29 inch, 26 inch and 650b wheel sizes are also common it has become more important.
The calculation is
Chain ring teeth, divided by sprocket teeth, multiplied by wheel diameter in inches.
That gives you a gear size in "inches" which is the theoretical equivalent size of the front wheel if you were riding an "ordinary bike" which is what they used to call penny farthings. Ordinaries had direct drive with no gearing, and the gear inches idea was to enable people to compare the later "safety bicycles' (the earliest bikes we would recognise as "bikes") with ordinaries.
So, 50/19 x 28 would produce a gear of 73.7 inches. (A 700c road tyre is roughly 28 inches diameter.)
For comparison, I ride 49/20 or 49/18 giving me choices of 68.6 or 76.2 inches. I'm 55 and not as fit as I was and I can ride either of these comfortably on rolling country lanes and up all of our local hills, such as they are. Your gear sounds "not unreasonable".
The wheel diameter can be ignored only if you are certain that everyone is talking about the same diameter wheels. When 700c was universal, this was OK. Now that 29 inch, 26 inch and 650b wheel sizes are also common it has become more important.
The calculation is
Chain ring teeth, divided by sprocket teeth, multiplied by wheel diameter in inches.
That gives you a gear size in "inches" which is the theoretical equivalent size of the front wheel if you were riding an "ordinary bike" which is what they used to call penny farthings. Ordinaries had direct drive with no gearing, and the gear inches idea was to enable people to compare the later "safety bicycles' (the earliest bikes we would recognise as "bikes") with ordinaries.
So, 50/19 x 28 would produce a gear of 73.7 inches. (A 700c road tyre is roughly 28 inches diameter.)
For comparison, I ride 49/20 or 49/18 giving me choices of 68.6 or 76.2 inches. I'm 55 and not as fit as I was and I can ride either of these comfortably on rolling country lanes and up all of our local hills, such as they are. Your gear sounds "not unreasonable".
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I agree, but we don’t know if the OP wants to learn. Especially given the premise of the question. I applaud the time you put in to explain it all out, I’m just not sure it was worth it. I could be wrong though, so I’m not pissing on your effort.
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Thanks for all the replies! Great info and yes I’m trying to lean all about the gearing. I put 25 on rear and 23 on front today and I like it. I’ll be playing around, I have a 16t rear and a few chainrings.