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Flying 200s

Old 06-29-17, 04:08 PM
  #26  
queerpunk
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If you hit 130 rpm, then you either have a typo in the gear, or you took an unbelievably inefficient line - my back-of-the-napkin calculated 130 rpm in a 49/13 to be about an 11.5.

i'd say that if you did a terrible line with undialed gear, then you can probably take off .5 seconds just via practice. Getting your timing, execution, and gear right. Doesn't have to take 3 months. Just takes a lot of flying 200s.
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Old 06-29-17, 04:15 PM
  #27  
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Originally Posted by queerpunk View Post
If you hit 130 rpm, then you either have a typo in the gear, or you took an unbelievably inefficient line - my back-of-the-napkin calculated 130 rpm in a 49/13 to be about an 11.5.

i'd say that if you did a terrible line with undialed gear, then you can probably take off .5 seconds just via practice. Getting your timing, execution, and gear right. Doesn't have to take 3 months. Just takes a lot of flying 200s.
I would guess there's plenty of things I have done wrong, apparently my line was a mile off and I've jumped like 20-25 metres late.

I suppose I'm also fairly inexperienced in general, only cycling about a year (training maybe 6 months).
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Old 06-29-17, 04:52 PM
  #28  
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well then you're off to a great start.

get to the track as often as you can. the more flying 200s you do, the faster you'll go. it won't always line up with how you feel - sometimes you'll feel great and wonder why you're .3 off of your best time - atmospheric conditions can play a big part.

but the more you do, the more you'll bring that time down.

i promise.
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Old 06-30-17, 12:38 AM
  #29  
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Topped out about 130rpm on a 49/13
Was it exactly 130rpm...or like 128 rpm? (each rpm matters a lot)

Using 23mm tires, 49t/13t @ 130rpm = 38.3mph / 61.7kph

If that were held for the entire 200M and the line were perfect, it would be 11.66"


ruudlaff, if you had a head unit that plots your cadence and speed every 0.1s of your ride, you'd see that you get a speed/cadence spike in the turns. This is due to leaning in the turns as your body goes faster with the lean and your wheels have to keep up. The system does a "reset" as your body slows down when you exit the turn and your wheels go slower.

Your average cadence is around 5rpm lower putting you at 12.1" speed assuming you rode on the measurement line the entire time. (Be careful reading that. Don't leave thinking that "I have 12.1 speed." You don't. You have 12.5 speed. What matters is what the stopwatch says.)

So the question is...what is a reasonable target for improvement? Say over a 3 month period for example?
Advice: Do more than 1 flying 200M.

12.5 your fist time is encouraging. Find out if the 12.5 was a fluke. Get your line right. Get your windup right. Calibrate your bike computer. Experiment with gears. Experiment with windup pacing strategies. Learn that running a stopwatch itself is a skill (your timer could be early or late with his/her thumb!)

The flying 200M should be trained and practiced like any other event. Don't only do it right before a monthly or annual sprint tournament.

You could be at 12.0 in 3 months...or 12.4. Nobody knows. Remember that wind resistance increases exponentially. To go from 12.5 to 12.4, 12.3, 12.2, 12.1 is exponentially more difficult.

Also, remember that the flying 200M is only a qualifying event to the sprint tournament. If you only learn to ride a flying 200M but forget to learn to sprint, you may miss the point of it all

I'm a "numbers guy". Numbers can be very very intoxicating and encouraging. Don't let them sing a Siren's song of promises to you to get your hopes up. One day during my 2nd season of racing, my SRM showed that I logged a max wattage of 2,300 watts. I was ready to sign up for the UCI world championships. I later learned that I shouldn't have let my SRM innards get wet when the bike was on top of the car

Look for several data points. Not just one. Congrats on the 12.5. Now do it again

Last edited by carleton; 06-30-17 at 12:42 AM.
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Old 06-30-17, 01:28 AM
  #30  
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129rpm - I rounded up haha

22mm tubs

I would like to think that it wasn't a fluke as I did 3 runs total, the first I got annoyed with myself as I didn't commit to it properly (nerves?) that was 12.7, second was 12.5 and third was 12.6 with about 3 minutes active rest between each.

Thanks for the help guys

Originally Posted by carleton View Post
Was it exactly 130rpm...or like 128 rpm? (each rpm matters a lot)

Using 23mm tires, 49t/13t @ 130rpm = 38.3mph / 61.7kph

If that were held for the entire 200M and the line were perfect, it would be 11.66"


ruudlaff, if you had a head unit that plots your cadence and speed every 0.1s of your ride, you'd see that you get a speed/cadence spike in the turns. This is due to leaning in the turns as your body goes faster with the lean and your wheels have to keep up. The system does a "reset" as your body slows down when you exit the turn and your wheels go slower.

Your average cadence is around 5rpm lower putting you at 12.1" speed assuming you rode on the measurement line the entire time. (Be careful reading that. Don't leave thinking that "I have 12.1 speed." You don't. You have 12.5 speed. What matters is what the stopwatch says.)



Advice: Do more than 1 flying 200M.

12.5 your fist time is encouraging. Find out if the 12.5 was a fluke. Get your line right. Get your windup right. Calibrate your bike computer. Experiment with gears. Experiment with windup pacing strategies. Learn that running a stopwatch itself is a skill (your timer could be early or late with his/her thumb!)

The flying 200M should be trained and practiced like any other event. Don't only do it right before a monthly or annual sprint tournament.

You could be at 12.0 in 3 months...or 12.4. Nobody knows. Remember that wind resistance increases exponentially. To go from 12.5 to 12.4, 12.3, 12.2, 12.1 is exponentially more difficult.

Also, remember that the flying 200M is only a qualifying event to the sprint tournament. If you only learn to ride a flying 200M but forget to learn to sprint, you may miss the point of it all

I'm a "numbers guy". Numbers can be very very intoxicating and encouraging. Don't let them sing a Siren's song of promises to you to get your hopes up. One day during my 2nd season of racing, my SRM showed that I logged a max wattage of 2,300 watts. I was ready to sign up for the UCI world championships. I later learned that I shouldn't have let my SRM innards get wet when the bike was on top of the car

Look for several data points. Not just one. Congrats on the 12.5. Now do it again
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Old 06-30-17, 11:33 PM
  #31  
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You need more than 3 minutes rest between efforts when training speed. With about 10 minutes rest, you might have actually seen a better decrease in time. You should be fresh as a daisy before each effort.
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Old 07-02-17, 09:02 PM
  #32  
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Originally Posted by taras0000 View Post
You need more than 3 minutes rest between efforts when training speed. With about 10 minutes rest, you might have actually seen a better decrease in time. You should be fresh as a daisy before each effort.
^^^ This!

Keep at it and get the line right, and then you can look at real comparisons between efforts. Don't be too specific about holding black, just don't go heading up to the blue line. Sweet spot cadence is at about 120rpm, give or take depending on your genetics mainly. Gear up a bit and go at it. If you've got the gearing to play with, keep gearing up and look at your times/speeds. When you slow down drop the gearing back.
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Old 07-03-17, 12:57 AM
  #33  
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As a reference, on my first competition last year in the flying 200m qualifier with the same stats as you (49/13, peak rpm of 129 and peak speed of 61.8 km/h) and with what I thought was a pretty good line, I got 12.146 seconds.

I'd say 12.1 is in you 100%.
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Old 07-03-17, 03:40 AM
  #34  
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Originally Posted by brawlo View Post
^^^ This!

Keep at it and get the line right, and then you can look at real comparisons between efforts. Don't be too specific about holding black, just don't go heading up to the blue line. Sweet spot cadence is at about 120rpm, give or take depending on your genetics mainly. Gear up a bit and go at it. If you've got the gearing to play with, keep gearing up and look at your times/speeds. When you slow down drop the gearing back.
This is interesting actually, so realistically holding 120rpm is the target? I have the gears to go anywhere from 49-53 in the front so that should give me plenty of opportunity to play about with it. I don't tend to have a problem turning anything generally, but I do burn myself out quick at the higher end of my cadence (anything 130 and up really).

Around the resting period, totally understand this. My session wasn't really built around the 200s that day, it was at the end of a bigger training session and I was using the 200s with the short rest periods as a way to blow myself up basically at the end. I'm going to make an effort to see what I can do with it given a proper prep.
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Old 07-03-17, 06:04 AM
  #35  
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Originally Posted by ruudlaff View Post
This is interesting actually, so realistically holding 120rpm is the target? I have the gears to go anywhere from 49-53 in the front so that should give me plenty of opportunity to play about with it. I don't tend to have a problem turning anything generally, but I do burn myself out quick at the higher end of my cadence (anything 130 and up really).
A lot of it depends upon your natural achievable cadence. I have seen guys that can hit 150 rpm and look comfortable and in control with the ability to hold it for a short duration.....I'm not one of them. When I get over 130, it looks like a frantic pace with me on the edge of control. Hitting a max of 130 rpm and being able to sustain 120-125 rpm's is my sweet spot. You want a high rpm, but one that you can control and maintain.....smooth is fast!!

Answering the following simple math equation may be able to help you understand the rpm thing a little better and how it pertains to you and the 200. Which is faster....94" gear at 130 rpm or 102" gear at 128 rpm?
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Old 07-03-17, 10:38 AM
  #36  
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Don't forget the other variable that goes into Cadence: Crank Length. With track cranks out there from 155 - 175mm in 2.5mm increments, there is a lot of variation. This also affects gearing. Riding a 98" gear on 155mm cranks is significantly harder than using 175mm cranks because your lever is 20mm shorter. You can feel this.

Further, it's generally easier to spin shorter cranks and it's easier to mash longer ones.

Then there is circumferential foot velocity: The speed at which your foot is moving in a circle. For a given gear and speed, shorter cranks will have your foot going around the circle with a faster velocity (meters/second) resulting in a faster cadence, longer will have your foot going around slower.

[sigh]

Then there is muscle activation rest periods ("micro rests"), basically how long you give your muscles a rest between applying force for the next pedal stroke.

There is a lot going on. I've trained and raced on 165mm, 167.5mm, 170mm, and 172.5mm cranks, and there is a qualitative and quantitative difference with each 2.5mm step.


I say all of that to say this:

- Longer cranks are harder to spin but easier to mash.
- Shorter cranks are easier to spin but harder to mash.
- Track Cranks come in 2.5mm increments for a reason.
- There is no best crank length for height, leg length, femur length, track, pursuits, F200M, kilo, etc... there is only best for you and your style...for that day

This will explain why it's hard for some to spin high cadences on their road bikes, because road bikes generally come with long cranks (for a given size) as the manufacturers err on the side of "mashing" and making the bike more mechanically efficient (feeling easier) as most customers won't spin more than 90rpm on a given ride.
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Old 07-03-17, 10:43 AM
  #37  
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Also, the dynamics of pedaling are different with different cranks lengths.

This won't matter much to beginners and maybe intermediate racers. But when you get to the point of fine-tuning, then it might matter.

Power is a function of torque on the pedal and cadence. Torque is a function of crank length. So, therefore, crank length affects how much power is recorded by power meters. Higher or lower numbers may not be good or bad, just understand that they are different.
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Old 07-03-17, 02:37 PM
  #38  
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Originally Posted by ruudlaff View Post
This is interesting actually, so realistically holding 120rpm is the target? I have the gears to go anywhere from 49-53 in the front so that should give me plenty of opportunity to play about with it. I don't tend to have a problem turning anything generally, but I do burn myself out quick at the higher end of my cadence (anything 130 and up really).

Around the resting period, totally understand this. My session wasn't really built around the 200s that day, it was at the end of a bigger training session and I was using the 200s with the short rest periods as a way to blow myself up basically at the end. I'm going to make an effort to see what I can do with it given a proper prep.
This is a poor way to get a training effect. It will work for you as a beginner, but only for a short while. If you're going to train a physical quality, then only train that quality in your workout. When you start to muddy the stresses that you put on your body, it gets confused as to how it is supposed to adapt. In the future, you'd be better off throwing on a light gear that doesn't stress you out, but lets you get to a decent speed, and practice your 200 line. This would be a good way to wind down after an effort.

Have a read with this in the Weightlifting thread - http://www.bikeforums.net/19638708-post837.html
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Old 07-03-17, 02:52 PM
  #39  
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Basically, doing F200s as an aerobic workout is like doing Clean and Jerks for time. All you end up doing is screwing up your technique (which matters a lot).
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Old 07-03-17, 02:55 PM
  #40  
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Originally Posted by taras0000 View Post
This is a poor way to get a training effect. It will work for you as a beginner, but only for a short while. If you're going to train a physical quality, then only train that quality in your workout. When you start to muddy the stresses that you put on your body, it gets confused as to how it is supposed to adapt. In the future, you'd be better off throwing on a light gear that doesn't stress you out, but lets you get to a decent speed, and practice your 200 line. This would be a good way to wind down after an effort.

Have a read with this in the Weightlifting thread - http://www.bikeforums.net/19638708-post837.html
That's fair. Although in fairness as a beginner I don't even know what I'm looking to train or where my strengths lie. I suppose that's what I'm trying to find out.
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Old 07-03-17, 04:51 PM
  #41  
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Originally Posted by ruudlaff View Post
That's fair. Although in fairness as a beginner I don't even know what I'm looking to train or where my strengths lie. I suppose that's what I'm trying to find out.
Anyone can learn the guitar by figuring it out on their own between books, YouTube, and websites. But, the beginning stages can be made easier when following a program (any program) under the guidance of an instructor (either one on one or in a small group). If anything, you avoid learning bad habits that you will have to spend time/energy unlearning later. Plus it will eliminate the mental anguish about "What should I be doing???"

The same applies for track racing.

Join any beginner class, clinic, etc.. that you can. Those are the most cost effective. Next is joining a club/team that focuses on track. Those teammates will have good advice, some of which will have paid coaches. Then when that gets you only so far, maybe consider paying a coach that knows how to coach track (not a roadie coach who thinks he/she knows.)
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Old 07-03-17, 05:43 PM
  #42  
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Originally Posted by carleton View Post
Then there is circumferential foot velocity: The speed at which your foot is moving in a circle. For a given gear and speed, shorter cranks will have your foot going around the circle with a faster velocity (meters/second) resulting in a faster cadence, longer will have your foot going around slower.
Other way around. For a longer crank the foot moves faster than a shorter crank at the same rpm. Hence why longer crank = lower rpm capability.

I have seen it mentioned a number of times that a school of thought is you have a maximal speed at which your foot can move and that is your limiter. It kind of makes sense, although it appears that is can be trainable, but no more than vertical jump (meaning you could increase it, but probably not by much)

I made the cut to ride roller derby at a local track carnival 18months ago. It was gear restricted, so I borrowed some 165 cranks (I normally run 175) because I can hit 30-40 rpm higher on the shorter cranks. Made it all the way to the semis against some junior spin kings. Big gears don't slow you down, even in rpm!
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Old 07-03-17, 06:24 PM
  #43  
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Originally Posted by brawlo View Post
Other way around. For a longer crank the foot moves faster than a shorter crank at the same rpm. Hence why longer crank = lower rpm capability.

I have seen it mentioned a number of times that a school of thought is you have a maximal speed at which your foot can move and that is your limiter. It kind of makes sense, although it appears that is can be trainable, but no more than vertical jump (meaning you could increase it, but probably not by much)

I made the cut to ride roller derby at a local track carnival 18months ago. It was gear restricted, so I borrowed some 165 cranks (I normally run 175) because I can hit 30-40 rpm higher on the shorter cranks. Made it all the way to the semis against some junior spin kings. Big gears don't slow you down, even in rpm!
Yup!

I used to have a spreadsheet where I did the math and had a table of cells for RPMs and crank lengths. If I remember correctly, every 2.5mm change in crank length translates to 2rpm change.

The result was an interpretation something like this:

Spinning 120rpm on 167.5mm cranks would have the same footspeed as spinning 118rpm on 170mm cranks and 122 rpm on 165mm cranks.

Better formatting:

165.0mm @ 122.0rpm
167.5mm @ 120.0rpm
170.0mm @ 118.0rpm
172.5mm @ 116.5rpm
175.0mm @ 115.0rpm

ALL 3 of those have the same circumferential foot speed of 2.10 meters/second. (The speed at which the rider's foot is moving in a circle).

It's all directly related.

So, you basically gained 7+ rpm by going from 175 to 165 cranks with the same foot speed!!

Last edited by carleton; 07-03-17 at 07:09 PM.
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Old 07-03-17, 07:18 PM
  #44  
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Now new racers are asking, "Pfft...if it's that easy to gain RPMs then why isn't everyone using 165...or 155mm cranks even?"

Why? Because you lose significant mechanical advantage with each 2.5mm shorter crank.

(Brawlo, I know you know this)

So, for every 2.5mm shorter crank, you have to go down something like 2 gear inches for a given amount of torque (the amount of force you can generate on the crank arm). So, this is why when people who ride 170mm cranks one season and their favorite scratch race gear is a 96", then they switch to 165mm cranks that same 96" feels HEAVY. Feels like a 98"...because it requires more torque (force). So, what you have to do is now make 94" your Scratch race gear using 165mm cranks.

It works the other way around, too. If you go longer, you can ride bigger gears with the same body you have now...but (based on the post above) you can't turn them as fast as you used to.

Physics and math are the great equalizers here.

Maybe don't think of longer/shorter cranks or bigger/smaller gears as better or worse. Think of them as fine tuning options when you know how to use them. They are the "Advanced Settings" for your track bike
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Old 07-03-17, 07:53 PM
  #45  
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Originally Posted by carleton View Post
165.0mm @ 122.0rpm
167.5mm @ 120.0rpm
170.0mm @ 118.0rpm
172.5mm @ 116.5rpm
175.0mm @ 115.0rpm

ALL 3 of those have the same circumferential foot speed of 2.10 meters/second. (The speed at which the rider's foot is moving in a circle).

It's all directly related.

So, you basically gained 7+ rpm by going from 175 to 165 cranks with the same foot speed!!
Now that's interesting. I've never been bothered to crunch the numbers. Going back to what I said about foot speed or tangential velocity limitations, my own experience kind of blows that out of the water then. Theoretically, going from 175mm cranks to 165 cranks at max 180rpm (175's) should only net me about 11rpm more. Obviously there's a whole lot more to it than simply foot speed. I hit 216rpm in one roller derby round where my highest cadence on 175s is around 180
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Old 07-03-17, 08:06 PM
  #46  
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Originally Posted by carleton View Post
Why? Because you lose significant mechanical advantage with each 2.5mm shorter crank.

(Brawlo, I know you know this)
Too damn well! At the carnival mentioned above due to the roller derby being between other events, I was rushing to change gears for the track events. I kept the gearing that I had been used to with my regular 175s. The 165s being 6% different really wasn't a lot, but it was enough to take the snap out of accelerations and I suffered badly in the keirin race where I ran a bigger gear. But that was going virtually overnight from 175-165. I honestly believe that after a month or so, you could condition yourself to adjust to the gear.

I began running 165s during 14/15 due to fit issues, however getting a new custom frame that actually fit me for 16/17 I went back to 175s. The biggest reason was due to the 165s being enough for some muscles not to work effectively. 175s saw better recruitment, but I'm not shorty at 6'5"
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Old 07-03-17, 08:10 PM
  #47  
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Originally Posted by brawlo View Post
Now that's interesting. I've never been bothered to crunch the numbers. Going back to what I said about foot speed or tangential velocity limitations, my own experience kind of blows that out of the water then. Theoretically, going from 175mm cranks to 165 cranks at max 180rpm (175's) should only net me about 11rpm more. Obviously there's a whole lot more to it than simply foot speed. I hit 216rpm in one roller derby round where my highest cadence on 175s is around 180
Yeah, there is.

Basically, 165s allow you to get closer to what you are capable of doing in terms of rate of muscular contractions. 175s are holding you back.

I bet if you put 165s on your track bike, you can do the "running on the pedals" thing where you do a standing lap out of the saddle.

Not saying you would be faster, but holding high cadences out of the saddle is difficult on longer cranks.

Also, with shorter cranks, your pedal stroke shifts at certain RPMs from a "down-down-down-down!" thing to a "forward-back, forward-back!" fast shuffle, thus engaging different fast twitch muscles.
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Old 07-03-17, 08:59 PM
  #48  
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Originally Posted by brawlo View Post
Too damn well! At the carnival mentioned above due to the roller derby being between other events, I was rushing to change gears for the track events. I kept the gearing that I had been used to with my regular 175s. The 165s being 6% different really wasn't a lot, but it was enough to take the snap out of accelerations and I suffered badly in the keirin race where I ran a bigger gear. But that was going virtually overnight from 175-165. I honestly believe that after a month or so, you could condition yourself to adjust to the gear.

I began running 165s during 14/15 due to fit issues, however getting a new custom frame that actually fit me for 16/17 I went back to 175s. The biggest reason was due to the 165s being enough for some muscles not to work effectively. 175s saw better recruitment, but I'm not shorty at 6'5"
Yeah, there are factors with leg length, too. The guy who had the fastest Man 1 lap at Masters (19.7") used 155mm cranks...but he's one of the shortest guys there. On top of that, he has relatively short legs and longer torso for his height. So, personal measurements do factor in.

Regarding getting used to it: You can't get blood from a turnip. You can only press so hard on the cranks on any given revolution. Physics says you have to press harder and more often using shorter cranks. But, the up side is that you can win with aerobic power by revving it up using lower max torque but higher rpms, like a rotary engine car. So, it's a different sort of power. THAT you will learn in that month. I mean, it's like, "OK, let me over-rev these cranks to start this sprint..." and you do it then shift pedal styles to maintain that new speed. I would touch 165RPM in match sprints....like it was nothin'. I also wasn't as gassed throughout the race day. I would even hang on mass start races longer than I usually would in years past.

Racing is really different between the crank lengths.

The down side is you could lose that "freight train" momentum that can carry you as you rest on the pedals.
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Old 07-03-17, 10:06 PM
  #49  
taras0000
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Originally Posted by brawlo View Post
Now that's interesting. I've never been bothered to crunch the numbers. Going back to what I said about foot speed or tangential velocity limitations, my own experience kind of blows that out of the water then. Theoretically, going from 175mm cranks to 165 cranks at max 180rpm (175's) should only net me about 11rpm more. Obviously there's a whole lot more to it than simply foot speed. I hit 216rpm in one roller derby round where my highest cadence on 175s is around 180
Carleton's quote related to the ~120rpm range. I'm pretty sure that as the RPMs go up, the differences become magnified. For someone who's larger than the average bear, I'm pretty sure this would have an effect as well, although my guess is that it would magnify even more for someone who is short and revving at high RPMs.
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Old 07-04-17, 01:39 AM
  #50  
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Originally Posted by taras0000 View Post
Carleton's quote related to the ~120rpm range. I'm pretty sure that as the RPMs go up, the differences become magnified. For someone who's larger than the average bear, I'm pretty sure this would have an effect as well, although my guess is that it would magnify even more for someone who is short and revving at high RPMs.
You are right, but the gains don't diverge from the 2rpm for each 2.5mm until you get into huge numbers (like over 300 rpm).

It stays pretty consistent up to 150rpm:

165mm @ 150rpm
167.5mm @ 148rpm
170mm @ 146rpm
172.5mm @ 143.5rpm
175mm @ 142rpm

Are all 2.59 or 2.60 m/s tangential velocity.

So, the differences as you gain 2.5mm crank length were:

-2rpm
-2rpm
-2.5rpm
-1.5rpm

Even up to 200rpm, the differences were:

-2rpm
-2rpm
-3rpm
-2rpm
(all are around 3.48 m/s)

If I get properly caffeinated, I'll calculate how much the torque difference is between cranks lengths 165mm - 175mm to hold a given speed...taking into account the angles of the pedal stroke that are actually producing power (not the dead spot parts). As the angle changes, the calculation changes as it's the sine of the angle multiplied by the crank length.

Over caffeinated and I'll do it in Watts
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