50/34 or 52/36 Crankset for racing (mostly flat)
08-05-23, 07:06 AM
#76
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I think we have all forgotten that apparently this guy has not ever raced yet.
.. and maybe forgot that the bike he plans to buy only comes with a 50-34 .... and maybe forgot that until he does race, on the specific course he actually races (as opposed to the ones he imagines racing) he will learn what he can and cannot do m, and will either make or not make the actually pertinent adjustments.
For all we know the guy would be best served by a 48-32. We have no real clue, and neither does the OP.
As far as I know, Cat 5 is "Pay your entry fee, pin on this number, show up at the start line." People who want to race merely have to .... race. Then everything will enter a new universe, one not just of imagination, but of sweat, pain, and the humiliation of being off the back ... and the OP can then decide not only what gears he needs, but what training ... or even if he really wants to race at all.
.. and maybe forgot that the bike he plans to buy only comes with a 50-34 .... and maybe forgot that until he does race, on the specific course he actually races (as opposed to the ones he imagines racing) he will learn what he can and cannot do m, and will either make or not make the actually pertinent adjustments.
For all we know the guy would be best served by a 48-32. We have no real clue, and neither does the OP.
As far as I know, Cat 5 is "Pay your entry fee, pin on this number, show up at the start line." People who want to race merely have to .... race. Then everything will enter a new universe, one not just of imagination, but of sweat, pain, and the humiliation of being off the back ... and the OP can then decide not only what gears he needs, but what training ... or even if he really wants to race at all.
08-05-23, 10:27 AM
#77
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Well, it’s a matter of simple physics, that’s all there is to that. Look it up; leverage is really a very basic concept.. I mean, you could go and spin the crankset of your bike with your finger both in the spider as close to the spindle as you can get, and then again out at the end of the crankarm; you should easily be able to feel the difference in force required to turn it at each location. It’s the same thing that happens at the pedals, just that the forces are larger, acting over a force range (i.e. torque) of something like 10nm to 190nm.
The ratio of chainring teet to cog teeth does not at all describe the amount of force required to turn the geartrain.
The ratio of chainring teet to cog teeth does not at all describe the amount of force required to turn the geartrain.
Anyone who wants to compare 50/34 vs 52/36 chainring gearing can simply look at an online gear calculator and see how their gear range compares with the same cassette. It's not a big difference. If there are very steep climbs then a 34/34 ratio is slightly better than a 36/34. Same at the other end for long fast downhills. Everything in between is just splitting hairs.
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08-05-23, 11:16 AM
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The advent of actual mechanical engineers on this site has definitely improved the level of discourse.
08-05-23, 12:44 PM
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There are those of us here who have engineering degrees (mine is specifically in mechanical engineering). It appears to me that you may have got confused between chainring size and crank arm length. As far as chainring size goes, there is no difference pedalling a 50T vs 52T chainring in an equivalent overall gear ratio when compensating for the difference on the cassette ratio. .
08-05-23, 02:30 PM
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No, the only thing I find confusing is why you cannot understand that I specifically and clearly said that the only change was the chainring. Changing chainring size changes the feel at the pedal. I’ve made that clear several times but you and others keep ignoring it, I suppose because none of you engineering geniuses have ever done pedaling torque analysis.
There are those of us here who have engineering degrees (mine is specifically in mechanical engineering). It appears to me that you may have got confused between chainring size and crank arm length. As far as chainring size goes, there is no difference pedalling a 50T vs 52T chainring in an equivalent overall gear ratio when compensating for the difference on the cassette ratio.
08-05-23, 02:55 PM
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It's like saying, "When you go up a hill it gets harder to pedal." Right, got it. Maybe the question was how much lower gear ratio does one need to go up a hill, or how steep of a hill can a rider handle before having to change gears. To keep saying, "I insist! Riding up hills requires more power than riding on flat ground or down hill" is a pointless assertion, because it's blatantly obvious.
08-05-23, 03:00 PM
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No, the only thing I find confusing is why you cannot understand that I specifically and clearly said that the only change was the chainring. Changing chainring size changes the feel at the pedal. I’ve made that clear several times but you and others keep ignoring it, I suppose because none of you engineering geniuses have ever done pedaling torque analysis.
Do you understand gear ratios? I have my doubts.
Last edited by PeteHski; 08-05-23 at 03:04 PM.
08-05-23, 03:47 PM
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No, the only thing I find confusing is why you cannot understand that I specifically and clearly said that the only change was the chainring. Changing chainring size changes the feel at the pedal. I’ve made that clear several times but you and others keep ignoring it, I suppose because none of you engineering geniuses have ever done pedaling torque analysis.
08-05-23, 04:17 PM
#84
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No, the only thing I find confusing is why you cannot understand that I specifically and clearly said that the only change was the chainring. Changing chainring size changes the feel at the pedal. I’ve made that clear several times but you and others keep ignoring it, I suppose because none of you engineering geniuses have ever done pedaling torque analysis.
Well, same rider on the same road at the same speed means same power. Then same gear ratio at same speed means same cadence.If same power at same cadence, then must have same torque which for same crank arm length requires same force on the pedal. So if cadence is the same and force on the pedal is the same, how can it feel different for different chainrings?
08-05-23, 04:33 PM
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Among artists it used to be said, "Just because no one understands what you are doing, doesn't mean you are an artist."
I guess with engineers ......
I guess with engineers ......
08-05-23, 08:23 PM
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The ladies doth protest too much, methinks.
