How do I calculate RPM from this sheet?
#1
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How do I calculate RPM from this sheet?
I'd like to pedal at 80 RPM, but I dont know what speed I am supposed to use for that.
I have the spreadsheet of my bike which gives me all the info I need to input here (into this auto calculator).
There is one little problem: I dont know what the "rear" information should be. Can anyone help me with giving me instructions how to find the relevant info on the "rear"? (I am guessing that it refers to the size of the gears in the cassette, right?)
There is one more thing: Where do I read the rpm info? The cadence tab...right? Do I need to go to 80 in cadence, and it will tell me in which gears I can reach 80 RPM, right?
Thanks in advance for the help.
I have the spreadsheet of my bike which gives me all the info I need to input here (into this auto calculator).
There is one little problem: I dont know what the "rear" information should be. Can anyone help me with giving me instructions how to find the relevant info on the "rear"? (I am guessing that it refers to the size of the gears in the cassette, right?)
There is one more thing: Where do I read the rpm info? The cadence tab...right? Do I need to go to 80 in cadence, and it will tell me in which gears I can reach 80 RPM, right?
Thanks in advance for the help.
#2
don't try this at home.
Riders usually count pedal strokes instead of using a chart. I used to count the right pedal for 20 seconds, then multiply by 3. This only works for a steady effort on flat ground, but it's good for finding out what different cadences feel like.
I looked up your bike's cogs. It appears to have an interesting "mega range" set, with six closely spaced gears, then a very big jump to the 34 low gear. Cogs:14,16,18,20,22,24,34
Here's your setup in Mike Sherman's Gear Calculator. When you click it, there will be a popup notice that "The current gear set has been added to the URL". Just click OK. All that means is that if you bookmark/favorite the page, it'll remember your settings.
There's a "Speed at X RPM" chart at the bottom. All the charts update on the fly as entries are changed.
The freewheel:
I looked up your bike's cogs. It appears to have an interesting "mega range" set, with six closely spaced gears, then a very big jump to the 34 low gear. Cogs:14,16,18,20,22,24,34
Here's your setup in Mike Sherman's Gear Calculator. When you click it, there will be a popup notice that "The current gear set has been added to the URL". Just click OK. All that means is that if you bookmark/favorite the page, it'll remember your settings.
There's a "Speed at X RPM" chart at the bottom. All the charts update on the fly as entries are changed.
The freewheel:
Last edited by rm -rf; 10-22-14 at 05:51 AM.
#3
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Um... the cadence chart finds the cadence. One axis is the gear you're in, the other axis is your speed. The speed chart has gear on one axis and cadence in 5 rpm increments on the other axis, and finds the speed that results.
As you guessed, the numbers you're expected to input for the rear are the teeth on the various cassette gears.
As you guessed, the numbers you're expected to input for the rear are the teeth on the various cassette gears.
#4
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[QUOTE=rm -rf;17238695]
Here's your setup in Mike Sherman's Gear Calculator.
/QUOTE]
This is just what I needed. I'd rather look at my speed and monitor my RPM through that (probably not the most accurate method, but the easiest I guess). I am recovering from a bit of a knee pain and for a week or two I dont wanna go above 80 RPM.
Thanks.
Here's your setup in Mike Sherman's Gear Calculator.
/QUOTE]
This is just what I needed. I'd rather look at my speed and monitor my RPM through that (probably not the most accurate method, but the easiest I guess). I am recovering from a bit of a knee pain and for a week or two I dont wanna go above 80 RPM.
Thanks.
Last edited by Elysium32; 10-22-14 at 07:51 AM.
#5
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Why do you need the computer ? (other than at work & shirking the job?) look at your feet and count for 15 sec. and 3 more quarters, for 60.
Last edited by fietsbob; 10-22-14 at 08:23 AM.
#6
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AFAIK the higher forces needed at lower rpms are not better for knees. Maybe you already know this and will be using lower rpm and lower forces.
Last edited by Igualmente; 10-22-14 at 08:32 AM.
#7
don't try this at home.
If your knees are sore, you want to stay at a higher cadence, with light force on the pedals. Keep shifting to an easier gear until you get to the point where it feels like no resistance at all, then shift to a slightly harder gear.
And in general, just take it easy on speed and distance until your knees improve.
And in general, just take it easy on speed and distance until your knees improve.
#9
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It was in another post that someone suggested 80 rpm to eliminate the pressure on my knee.
I guess 80 RPM is like a lower limit or something. And I totally agree with you that apart from the RPM, a lesser force gear is needed too. I am using 2/4-5 or 3/4-5 gear settings in 80 RPM now to eliminate pressure on my knee.
I guess 80 RPM is like a lower limit or something. And I totally agree with you that apart from the RPM, a lesser force gear is needed too. I am using 2/4-5 or 3/4-5 gear settings in 80 RPM now to eliminate pressure on my knee.