Hilly Course Cassette (Page 2)
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2016-08-01 11:24 AM in reply to: nc452010 |
Pro 6582 Melbourne FL | Subject: RE: Hilly Course Cassette Originally posted by nc452010 My typical 52.1 mi. route has 2,179' gain. That's not a hilly ride, here. I'm not concerned with whether or not I can go up the hill. I'm concerned about how much energy I could save by utilizing different cassettes. I don't think you are 'saving energy' per se if the speed doesn't change. You want to optimize the cadence range via gearing to where you are more efficient. For example my spreadsheet calculates that if you're in the small 39 ring and large 25 cog going 8 mph, your at ~66 rpms. A 28 cog will let you go 8 mph at ~74 rpms, or a 32 cog doing ~8 mph is at 84 rpms. Everyone is different on the cadence range but I would be ok spinning at 74 rpms for 7.5 minutes for that 1 mile versus 66 rpms.FWIW, I run a 52/34 ring set on my bike and 12/25 cassette. I can handle just about anything with that combo, about 2% more gearing than a 39/28.
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2016-08-01 12:10 PM in reply to: Donto |
Expert 2852 Pfafftown, NC | Subject: RE: Hilly Course Cassette Originally posted by Donto Originally posted by nc452010 My typical 52.1 mi. route has 2,179' gain. That's not a hilly ride, here. I'm not concerned with whether or not I can go up the hill. I'm concerned about how much energy I could save by utilizing different cassettes. I don't think you are 'saving energy' per se if the speed doesn't change. You want to optimize the cadence range via gearing to where you are more efficient. For example my spreadsheet calculates that if you're in the small 39 ring and large 25 cog going 8 mph, your at ~66 rpms. A 28 cog will let you go 8 mph at ~74 rpms, or a 32 cog doing ~8 mph is at 84 rpms. Everyone is different on the cadence range but I would be ok spinning at 74 rpms for 7.5 minutes for that 1 mile versus 66 rpms.FWIW, I run a 52/34 ring set on my bike and 12/25 cassette. I can handle just about anything with that combo, about 2% more gearing than a 39/28.
I'm curious as to what the difference in power output would be (between the two scenarios). I've been experimenting with using a bigger gear than what feels "normal" when I ride. What I've found is, on false flats, my speed increases when I go to the bigger gear sometimes. But, there has to be a point of diminishing returns. I would think I'm expending more power. I just don't know how much. I appreciate the reply, Donto. I'm trying my best to order a Power2Max PM today........if I can get them to respond to me....lol. |
2016-08-01 1:30 PM in reply to: nc452010 |
Not a Coach 11473 Media, PA | Subject: RE: Hilly Course Cassette Originally posted by nc452010 Originally posted by Donto I'm curious as to what the difference in power output would be (between the two scenarios). I've been experimenting with using a bigger gear than what feels "normal" when I ride. What I've found is, on false flats, my speed increases when I go to the bigger gear sometimes. But, there has to be a point of diminishing returns. I would think I'm expending more power. I just don't know how much. I appreciate the reply, Donto. I'm trying my best to order a Power2Max PM today........if I can get them to respond to me....lol. Originally posted by nc452010 My typical 52.1 mi. route has 2,179' gain. That's not a hilly ride, here. I'm not concerned with whether or not I can go up the hill. I'm concerned about how much energy I could save by utilizing different cassettes. I don't think you are 'saving energy' per se if the speed doesn't change. You want to optimize the cadence range via gearing to where you are more efficient. For example my spreadsheet calculates that if you're in the small 39 ring and large 25 cog going 8 mph, your at ~66 rpms. A 28 cog will let you go 8 mph at ~74 rpms, or a 32 cog doing ~8 mph is at 84 rpms. Everyone is different on the cadence range but I would be ok spinning at 74 rpms for 7.5 minutes for that 1 mile versus 66 rpms.FWIW, I run a 52/34 ring set on my bike and 12/25 cassette. I can handle just about anything with that combo, about 2% more gearing than a 39/28.
If you go the same speed, you are putting out the same watts. If your speed increases at a bigger gear, you are putting out more watts. The question is simply if the cadence that your gearing allows makes the wattage output more comfortable/sustainable. And that determines whether you will be better 'spinning' up at 84rpms or 'grinding' up at 66. The latter requires more torque be applied each revolution and at some point will become uncomfortable. FWIW, I'd be fine 'grinding' at 66 for a period of time. The risk is that you are forced into putting out even more watts to maintain whatever a 'comfortable grinding' cadence is for you on some hills because you don't have enough gears. I know that's your question, but it's difficult to answer as a generalization. I assume you have standard chainrings (ie, 53/39), so I would lean towards the 12-28. |
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