Road Cycling - Here's a list of pro crank lengths for you tekkies!

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hiracer
09-15-05, 02:24 PM
FWIW, in the recumbent world there is a somewhat major movement toward short chanks, some guys going down to 151mm. 165 and 160 on average sized guys is not unusual. I moved from 175 to 170 and found it faster.

OTOH, I have 175 mm on my Sarthe and am thinking of going 177.5 mm someday rather than down.


biker7
09-15-05, 02:43 PM
FWIW, in the recumbent world there is a somewhat major movement toward short chanks, some guys going down to 151mm. 165 and 160 on average sized guys is not unusual. I moved from 175 to 170 and found it faster.

OTOH, I have 175 mm on my Sarthe and am thinking of going 177.5 mm someday rather than down.
True...believe in the 'bent community this may be to improve sight of the road and aerodynamics with little if any downside to power imparted to the bike. I have owned road bikes with 165mm cranks I felt I was as fast on...perhaps faster in a sprint than on longer cranks.
George

hiracer
09-15-05, 02:55 PM
George:

The shorter cranks are to increase rpm. For some reason that leads to better efficiency. A buddy of mine just went from 170 to 151 and says his average rmp is now 120, easy. Seems natural to him at this point.

I put 140mm on my wife's bent but she is only 5'.

Also, damage to knees is a major risk in recumbency because the seatback gives you something to push against. Mashers can easily blow their needs out if not careful. Spin, spin, is the advice.

I went for two years riding only bents. When I jumped on my mtb, the first thing I noticed is how short the cranks seemed. In fact, they were 5mm longer! Just didn't seem that way.


lee_eldridge
09-15-05, 03:17 PM
If you want to get more 'leverage' or 'torque', drop a tooth in the front, or add a tooth in the back. Longer cranks do nothing unless you have the range of motion to spin them correctly and not put wierd stresses on your hips and knees.

biker7
09-15-05, 04:58 PM
George:

The shorter cranks are to increase rpm. For some reason that leads to better efficiency. A buddy of mine just went from 170 to 151 and says his average rmp is now 120, easy. Seems natural to him at this point.

I put 140mm on my wife's bent but she is only 5'.

Also, damage to knees is a major risk in recumbency because the seatback gives you something to push against. Mashers can easily blow their needs out if not careful. Spin, spin, is the advice.

I went for two years riding only bents. When I jumped on my mtb, the first thing I noticed is how short the cranks seemed. In fact, they were 5mm longer! Just didn't seem that way.
An interesting trend toward shorter cranks as the evolution of 'bents is a bit behind conventional bikes...so perhaps still evolving. Thanks for setting the record straight.
George

biker7
09-15-05, 05:00 PM
If you want to get more 'leverage' or 'torque', drop a tooth in the front, or add a tooth in the back. Longer cranks do nothing unless you have the range of motion to spin them correctly and not put wierd stresses on your hips and knees.
Agree...would say much of the discussion in this thread supports your comments.
A good way of putting it.
George

tbreihan
09-15-05, 05:19 PM
If you want to get more 'leverage' or 'torque', drop a tooth in the front, or add a tooth in the back. Longer cranks do nothing unless you have the range of motion to spin them correctly and not put wierd stresses on your hips and knees.

I would have to say that I generally agree with what you say and also what Sheldon Brown was quoted as saying on the previous page. Longer crank arms will only effectively make the overall gearing of the bike taller; if mashing on 53-12 at 50 PPM is the most your muscles can handle, switching to longer crankarms, you won't have any more effective leverage. It will only effectlively put you in a higher gear and make it harder to turn the cranks. Also, it may do damage to your knees/hips by driving them into an unsuitable range of motion.

I think that you should use the longest cranks that feel comfortable for you/your riding style. I am tall (6'2") with a 35-1/2" inseam. I ride a 57cm LeMond frame with either 172.5mm or 175mm cranks and I like to spin. That's what works for me. According to Zinn, I should be using 185-190mm cranks, which I know would NOT work for me!

hiracer
09-15-05, 05:45 PM
An interesting trend toward shorter cranks as the evolution of 'bents is a bit behind conventional bikes...so perhaps still evolving. Thanks for setting the record straight.
George

Waaay behind. Thanks to the UCI.

DannoXYZ
09-15-05, 06:29 PM
I would have to say that I generally agree with what you say and also what Sheldon Brown was quoted as saying on the previous page. Longer crank arms will only effectively make the overall gearing of the bike taller; if mashing on 53-12 at 50 PPM is the most your muscles can handle, switching to longer crankarms, you won't have any more effective leverage. It will only effectlively put you in a higher gear and make it harder to turn the cranks. Also, it may do damage to your knees/hips by driving them into an unsuitable range of motion.

Longer cranks will give you the same effect as LOWER gearing. What you want to compare is the total distance the pedal-spindle moves per revolution vs. linear-distance the bike moves. It's the ratio of bike-distance to pedal-spindle distance that's the leverage-ratio.

The other way to compare leverage-ratio is instantenous linear velocity of the pedal-spindle vs. the linear velocity of the tire's outermost edge.

ed073
09-15-05, 06:42 PM
Longer cranks will give you the same effect as LOWER gearing. What you want to compare is the total distance the pedal-spindle moves per revolution vs. linear-distance the bike moves. It's the ratio of bike-distance to pedal-spindle distance that's the leverage-ratio.

The other way to compare leverage-ratio is instantenous linear velocity of the pedal-spindle vs. the linear velocity of the tire's outermost edge.


holy crap.

I remember when bike racing was for guys who finished school at 17 and would struggle to make sense of a route map....

:D

Wurm
09-15-05, 10:41 PM
Man you have short legs for your height..must be a sight to watch you spin those 175mm cranks.
You must be special ;)...especially since there are TDF racers on shorter cranks the same size as you.
Placebo.
George

What, you're back to argue some more, Mr. Know It All? I really couldn't care less what TDF racers use, OR what Brown says, despite your hero worship of anything he spouts. I know there is a difference for me between 172's and 175's.

I found this out quite by mistake. I had ordered a set of 172 cranks to replace a set of OEM's, thinking what was on the bike originally were 172's, but the OEM's were 175's. I installed the new 172's and on the first ride, I knew something was wrong: over a very well-known course I had to shift to at least one gear lower up the climbs, I spent a helluva lot more energy doing the rest of the course, my time was slower, and my legs were feeling much more tired than usual. I wasn't spinning any faster on the new 172's than I had been on the OEM 175's. If anything, the new cranks should have spun quicker/easier than the old ones because they were a fair amount lighter.

When I got home, I looked at the new and OEM cranks and noticed the size difference. I remounted the OEM 175's and immediately rode the same course again. Everything was back to 'normal' and I was doing the course at the usual faster pace. BTW - nothing else had changed: I used the same chainrings, same pedals, same bike. Only the crankarm length was different.

Sent the new 172's back to the dealer and he returned a set in 175. No problems since.

Placebo my ass. I had no knowledge on the first ride that the arms were of different lengths. The second ride merely confirmed what my body had been telling me.

You shouldn't make blanket assumptions based on theories, Bullwinkle.

sirshane13
09-15-05, 11:05 PM
I'm starting to get the impression that crank arm length is as critical as stem length, saddle position, pedal stack height, handlebar width, etc. So if true, it would mean that the size really is more dependent upon the unique geometry/anatomy of the rider.

alanbikehouston
09-15-05, 11:25 PM
What, you're back to argue some more, Mr. Know It All? I really couldn't care less what TDF racers use, OR what Brown says, despite your hero worship of anything he spouts....Placebo my ass. ...You shouldn't make blanket assumptions based on theories, Bullwinkle.

Well, I'm guessing someone did not get an "A" back in charm school...

Wurm
09-15-05, 11:37 PM
Well, I'm guessing someone did not get an "A" back in charm school...

You guessed right, Alan. I was usually a "B+" student in charm, but I'm always an "A" when it comes to giving as good as I get. ;)

tbreihan
09-15-05, 11:50 PM
Longer cranks will give you the same effect as LOWER gearing. What you want to compare is the total distance the pedal-spindle moves per revolution vs. linear-distance the bike moves. It's the ratio of bike-distance to pedal-spindle distance that's the leverage-ratio.

The other way to compare leverage-ratio is instantenous linear velocity of the pedal-spindle vs. the linear velocity of the tire's outermost edge.

When you say lower gearing, you are referring to a numerically lower ratio, correct? Which would indicate a 'taller' gear.

In other words, switching to longer crank arms has the same effect as switching to a larger chainring; less PPM for a given speed (linear distance covered) with a subsequent decrease in mechanical advantage (higher effort.)

Is this correct? This would be my assumption.

531Aussie
09-16-05, 12:41 AM
holy crap.

I remember when bike racing was for guys who finished school at 17 and would struggle to make sense of a route map....

:Dha!!:D

"That's funny George. You're very quick. I feel like I, like I don't have to explain every little
thing to you. You understand everything immediately.

531Aussie
09-16-05, 12:51 AM
I found this out quite by mistake. I had ordered a set of 172 cranks to replace a set of OEM's, thinking what was on the bike originally were 172's, but the OEM's were 175's. I installed the new 172's and on the first ride, I knew something was wrong: .ooh, oo oo, this is my big chance to tell my story.......again :p

One day, about 3 years ago, I dusted off my old 'race' bike that I hadn't ridden for a few years, and road off to uni for my regular commute. Shortly into the ride, I couldn't work out why I was FLYYYING up the hills....I FELT LIKE SUPERMAN!!! :D I knew I had the same crappy 7 speed Maillard cluster with the same ratios, so I couldn't figure it out. I rolled up my shorts to see if my thighs had grown 2" over night, but alas, no:)

I eventually remembered that this bike had 175s on it, my regular commuter bike had 170s. Since then, I had the 'long cranks' thing in my head, and eventually ended up with 180s

How would you rate my story? Polly wolly crappy?

Starclimber
09-16-05, 01:44 AM
When you say lower gearing, you are referring to a numerically lower ratio, correct? Which would indicate a 'taller' gear.

In other words, switching to longer crank arms has the same effect as switching to a larger chainring; less PPM for a given speed (linear distance covered) with a subsequent decrease in mechanical advantage (higher effort.)

Is this correct? This would be my assumption.


Noooooooooooo.....the chainring is exactly the same size, regardless of crank length. The lever turning the chainring is longer. If the load at the wheel is the same, then the force required at the pedal is LOWER. The pedal will travel a larger circle, though, so the work done is nearly the same. Swinging those meaty legs in larger arcs takes a bit more energy though.

Wurm
09-16-05, 01:45 AM
Don't know how your "story" rates 531, but as for mine that's what really happened. No one, including Sheldon Brown or anyone like him, can tell me that crankarm length doesn't make a difference.

531Aussie
09-16-05, 01:51 AM
I agree with you: I have no doubt that longer cranks equals more leverage, or torque, or power, or whatever we wanna call it. Sorry if you thought i was being sarcastic.

My 'story' is true; I just tried to 'jazz' it up a bit because I know you've heard it before :). Like I said, I'm on 180s.

531Aussie
09-16-05, 02:07 AM
if the best cyclists in the world were faster on any particular crank length, they would be on them period. but the top time-trialing pros DO use longer cranks period, when 'ride alone' power matters, during time-trials and hills. In other words, when slipstreaming, sudden accelerations, and all-out sprints are irrelevant, the 'contenders' go for the longer cranks. The pros that don't give a stuff about these stages, such as the sprinters and others who are crap at time-trialing and climbing, don't seem to bother changing cranks

Both Indurain and Sosenko used 190s for their hour records (granted, they are both very tall and were on fixed geared bikes) and little Pantani used 180s on hills?....WOW!

In my opninion, the extra leverage is a no brainer; the thing that should be queried is the impact that a lower saddle (required for longer cranks) has on power output. But, the pros seem to do ok :)

DannoXYZ
09-16-05, 03:30 AM
Longer cranks will give you the same effect as LOWER gearing. What you want to compare is the total distance the pedal-spindle moves per revolution vs. linear-distance the bike moves. It's the ratio of bike-distance to pedal-spindle distance that's the leverage-ratio.

The other way to compare leverage-ratio is instantenous linear velocity of the pedal-spindle vs. the linear velocity of the tire's outermost edge.
When you say lower gearing, you are referring to a numerically lower ratio, correct? Which would indicate a 'taller' gear.

In other words, switching to longer crank arms has the same effect as switching to a larger chainring; less PPM for a given speed (linear distance covered) with a subsequent decrease in mechanical advantage (higher effort.)

Is this correct? This would be my assumption.No, it's the other way around (the chain is not attached to the pedal BTW). Taller gears are harder to push. So going from 52x15t -> 52x13t is going into a taller gear (harder to push). Going from 170mm cranks to 175mm cranks is like going into a lower gear, like 52x13t -> 52x14t (easier to push). Here's how it works out mathematically:

170mm cranks = 107cm circumference (pedal's motion per revolution)
52x13t gear = 0.250:1 = 862cm travel per crank-rev = 0.124:1 pedal-to-travel ratio
52x14t gear = 0.269:1 = 800cm travel per crank-rev = 0.133:1 pedal-to-travel ratio
52x15t gear = 0.288:1 = 747cm travel per crank-rev = 0.143:1 pedal-to-travel ratio
38x13t gear = 0.342:1 = 630cm travel per crank-rev = 0.170:1 pedal-to-travel ratio
38x14t gear = 0.368:1 = 585cm travel per crank-rev = 0.183:1 pedal-to-travel ratio
38x15t gear = 0.395:1 = 546cm travel per crank-rev = 0.196:1 pedal-to-travel ratio

180mm cranks = 113cm circumference
52x13t gear = 0.250:1 = 862cm travel per crank-rev = 0.131:1 pedal-to-travel ratio
52x14t gear = 0.269:1 = 800cm travel per crank-rev = 0.141:1 pedal-to-travel ratio
52x15t gear = 0.288:1 = 747cm travel per crank-rev = 0.151:1 pedal-to-travel ratio
38x13t gear = 0.342:1 = 630cm travel per crank-rev = 0.180:1 pedal-to-travel ratio
38x14t gear = 0.368:1 = 585cm travel per crank-rev = 0.193:1 pedal-to-travel ratio
38x15t gear = 0.395:1 = 546cm travel per crank-rev = 0.207:1 pedal-to-travel ratio

Notice first that going from 170->180mm cranks, with just 1cm longer cranks, the path of the circumference that you push the pedal through increases by 6cm.

Also look at initial gear-reductions. The 52x13t gear reduces torque by 0.250 (1/4) in going from the crank to the rear-wheel. A lower gear of 38x15t has more mechanical leverage and reduces torque by only 0.395 times. As you shift into lower and lower gears, the mechanical leverage increases and the pedals are easier to push at the same speed. Your feet moves through a larger distance for the same wheel-revolution (you spin more), or the converse, the wheel rotates less for the same pedal-revolution.

The same effect is noticed in going to longer cranks in the same gears. Whereas the 52x13t gear with 170mm crank has an overall 0.124 reduction, the 180mm crank has a 0.131 reduction for more leverage. In fact, the 180mm crank gives about the same leverage in a 52x13t gear as the 170mm crank using 52x14t. What this means is that pushing a bigger gear 52x13t with 180mm crank will "feel" as easy as pushing a 52x14t gear with 170mm cranks. So for the same muscle-effort, you can push a bigger gear with a longer crank. Let's see how that translates into power-generated...

Given that:

power = work/time = (force*distance)/time

if you keep force from muscle-exertion on the pedals fixed, like you're already pushing as hard as you can, the only way to increase power-output is to increase either the distance that you push the pedals (lower-gears or longer cranks) or to decrease the time it takes for one crank-revolution (higher-RPMs). Let's assume that we maintain the same RPMs with both set of cranks, we can simplify the equation to:

power = (force*distance)

and let's say we're pushing on the pedal with the same force in both cases we can further reduce the equation to:

power = distance

then make a ratio of the two pedal-circumferences:

_powerA___ = __powerB_
distance107 distance113

and we end up with:

powerB = powerA*1.056

So with exactly the same RPM and exactly the same pedal-effort on both 180mm vs. 170mm cranks, the 6cm longer pedal-travel of 113cm vs 107cm gives 5.6% more power. :)

Wurm
09-16-05, 08:57 AM
So with exactly the same RPM and exactly the same pedal-effort on both 180mm vs. 170mm cranks, the 6cm longer pedal-travel of 113cm vs 107cm gives 5.6% more power. :)

And THAT is not insignificant.

Whew, my head hurts!

tbreihan
09-16-05, 09:07 AM
No, it's the other way around (the chain is not attached to the pedal BTW). Taller gears are harder to push. So going from 52x15t -> 52x13t is going into a taller gear (harder to push). Going from 170mm cranks to 175mm cranks is like going into a lower gear, like 52x13t -> 52x14t (easier to push). Here's how it works out mathematically:

170mm cranks = 107cm circumference (pedal's motion per revolution)
52x13t gear = 0.250:1 = 862cm travel per crank-rev = 0.124:1 pedal-to-travel ratio
52x14t gear = 0.269:1 = 800cm travel per crank-rev = 0.133:1 pedal-to-travel ratio
52x15t gear = 0.288:1 = 747cm travel per crank-rev = 0.143:1 pedal-to-travel ratio
38x13t gear = 0.342:1 = 630cm travel per crank-rev = 0.170:1 pedal-to-travel ratio
38x14t gear = 0.368:1 = 585cm travel per crank-rev = 0.183:1 pedal-to-travel ratio
38x15t gear = 0.395:1 = 546cm travel per crank-rev = 0.196:1 pedal-to-travel ratio

180mm cranks = 113cm circumference
52x13t gear = 0.250:1 = 862cm travel per crank-rev = 0.131:1 pedal-to-travel ratio
52x14t gear = 0.269:1 = 800cm travel per crank-rev = 0.141:1 pedal-to-travel ratio
52x15t gear = 0.288:1 = 747cm travel per crank-rev = 0.151:1 pedal-to-travel ratio
38x13t gear = 0.342:1 = 630cm travel per crank-rev = 0.180:1 pedal-to-travel ratio
38x14t gear = 0.368:1 = 585cm travel per crank-rev = 0.193:1 pedal-to-travel ratio
38x15t gear = 0.395:1 = 546cm travel per crank-rev = 0.207:1 pedal-to-travel ratio

Notice first that going from 170->180mm cranks, with just 1cm longer cranks, the path of the circumference that you push the pedal through increases by 6cm.

Also look at initial gear-reductions. The 52x13t gear reduces torque by 0.250 (1/4) in going from the crank to the rear-wheel. A lower gear of 38x15t has more mechanical leverage and reduces torque by only 0.395 times. As you shift into lower and lower gears, the mechanical leverage increases and the pedals are easier to push at the same speed. Your feet moves through a larger distance for the same wheel-revolution (you spin more), or the converse, the wheel rotates less for the same pedal-revolution.

The same effect is noticed in going to longer cranks in the same gears. Whereas the 52x13t gear with 170mm crank has an overall 0.124 reduction, the 180mm crank has a 0.131 reduction for more leverage. In fact, the 180mm crank gives about the same leverage in a 52x13t gear as the 170mm crank using 52x14t. What this means is that pushing a bigger gear 52x13t with 180mm crank will "feel" as easy as pushing a 52x14t gear with 170mm cranks. So for the same muscle-effort, you can push a bigger gear with a longer crank. Let's see how that translates into power-generated...

Given that:

power = work/time = (force*distance)/time

if you keep force from muscle-exertion on the pedals fixed, like you're already pushing as hard as you can, the only way to increase power-output is to increase either the distance that you push the pedals (lower-gears or longer cranks) or to decrease the time it takes for one crank-revolution (higher-RPMs). Let's assume that we maintain the same RPMs with both set of cranks, we can simplify the equation to:

power = (force*distance)

and let's say we're pushing on the pedal with the same force in both cases we can further reduce the equation to:

power = distance

then make a ratio of the two pedal-circumferences:

_powerA___ = __powerB_
distance107 distance113

and we end up with:

powerB = powerA*1.056

So with exactly the same RPM and exactly the same pedal-effort on both 180mm vs. 170mm cranks, the 6cm longer pedal-travel of 113cm vs 107cm gives 5.6% more power. :)

Great explanation! Thanks!

I am pretty good at figuring this stuff out with cars... When it comes to bikes, though, I have some kind of mental block about it.

Anyway, thanks for the detailed post.

hiracer
09-16-05, 11:52 AM
I agree with you: I have no doubt that longer cranks equals more leverage, or torque, or power, or whatever we wanna call it. Sorry if you thought i was being sarcastic.

My 'story' is true; I just tried to 'jazz' it up a bit because I know you've heard it before :). Like I said, I'm on 180s.

Actually you don’t necessarily get more leverage by moving up in crank length.

First, if you move up in crank length, but then pick a lower gearing combination, the effective mechanical leverage is the same.

Second, you are ignoring one-half of the system. Your legs can deliver much more power when they are near full extension, as compared to near full articulation. Compare 1 / 4 squats against 1 / 2 squats. You can definitely squat more with 1 / 4 squats because you lose leverage bending your knees and hips so much with 1 / 2 squats. You can squat even less with full squats because you lose even more leverage.

Third, with a custom bike, long cranks translate into a higher BB which in turn increases the center of mass, which affects just about everything in bike handling. For off the shelf bikes, long cranks translate into more ground interference.

Fourth, when joints bend under stress, the risk of injury increases with the amount of bending. You can blow your knees out much easier with longer cranks.

This is not an argument against longer cranks. It’s an argument that you cannot blindly move up in crank length and be guaranteed that good things will result. Like most things in life, the answer is, “It depends.”

531Aussie
09-16-05, 12:30 PM
Actually you don’t necessarily get more leverage by moving up in crank length.
Second, you are ignoring one-half of the system. Your legs can deliver much more power when they are near full extension, as compared to near full articulation. Compare 1 / 4 squats against 1 / 2 squats. You can definitely squat more with 1 / 4 squats because you lose leverage bending your knees and hips so much with 1 / 2 squats. You can squat even less with full squats because you lose even more leverage..”I mentioned the seat height thing toward the end of post #71. I tend to agree somewhat with the squating/leg press analogy (and it drives me nuts thinking about it during some rides), in that we are strongest in the last few degrees of the leg pressing movement, but does that mean we'd be better off on 140mm cranks which would put us much higher over the pedals through the 12 o'clock-4 o'clock oart of the down stroke? I would tend to say 'no', based on my own recent 'experiments' with crank lengths 170, 175 and 180mm. The two prime aspects of this topic (among the many), I believe, is the trade off between extra leverage (or 'torque', or whatever) and the compromised (lower) saddle position.

I'm no expert, but I think the squating analogy is too simple. The speed of muscle contractions, etc, etc, etc also comes into it. Andrew Bradley has a big website site devoted to this topic, and he tries to cover all of the conundrums, including this one:"the popular idea that the legs are most powerful when nearly straight is most probably a myth" http://www.cranklength.info/saddle-height.htm

If I'm gunna quote him, I should be fair and quote the opening line on his site regarding leverage:
"If you know anything about physics you will have realised that more crank leverage, of itself, does not mean "more power". Any power gains via crank arm length would have to be due to physiological reasons.


As you say, I also have no doubt that the extra leg flexion with longer cranks puts much more strain on the knees

DannoXYZ
09-17-05, 01:25 PM
I mentioned the seat height thing toward the end of post #71. I tend to agree somewhat with the squating/leg press analogy (and it drives me nuts thinking about it during some rides), in that we are strongest in the last few degrees of the leg pressing movement, but does that mean we'd be better off on 140mm cranks which would put us much higher over the pedals through the 12 o'clock-4 o'clock oart of the down stroke? I would tend to say 'no', based on my own recent 'experiments' with crank lengths 170, 175 and 180mm. The two prime aspects of this topic (among the many), I believe, is the trade off between extra leverage (or 'torque', or whatever) and the compromised (lower) saddle position.

Remember also that we're talking about two different things here. The legs will be at full extension and maximum efficiency in BOTH cases with 170mm or 180mm cranks once you adjust the seat accordingly. And yes, the legs will be exerting at full force on both cranks.

It's really not about force, but about power, which introduces a time and distance variable. It's like torque, power, acceleration and top-speed with cars, people don't get how those are related as well. The bottom line with cranks is that given the same muscle output, and assuming you can spin it as fast, you'll end up with more power given the same force input from the muscles.

hiracer
09-17-05, 01:44 PM
Remember also that we're talking about two different things here. The legs will be at full extension and maximum efficiency in BOTH cases with 170mm or 180mm cranks once you adjust the seat accordingly. And yes, the legs will be exerting at full force on both cranks.

It's really not about force, but about power, which introduces a time and distance variable. It's like torque, power, acceleration and top-speed with cars, people don't get how those are related as well. The bottom line with cranks is that given the same muscle output, and assuming you can spin it as fast, you'll end up with more power given the same force input from the muscles.

Long cranks bend the knees more which translates into more stress on the knees and less mechanical leverage for the legs.

Implying that crank lengths do not affect muscle output or maximum spin rates is wrong for the majority of the cycling popuation.

I'm not against longer cranks lenghts per se, just overly simplified explanations of what they do, as in "Longer cranks give you more leverage."

Chucklehead
09-17-05, 05:10 PM
You guessed right, Alan. I was usually a "B+" student in charm, but I'm always an "A" when it comes to giving as good as I get. ;)

how'd you do in rip-off class?

Wurm
09-17-05, 06:23 PM
how'd you do in rip-off class?

Not as well as some that I know.

TheDTrain
09-17-05, 08:09 PM
Here's a new signature for you.

"If you ripoff your neighbor and steal his stuff, then you're a dirty smelly assfoe."
- TheDTrainite Proverb

Starclimber
09-17-05, 08:18 PM
Crankenstein's Remonster...talk about leverage! The dangers of nezpotism, laid bare. Well sniffed, Mr. Dog.

bbattle
09-17-05, 09:35 PM
Nice physics lesson, Danno. I guess I'll keep my 175mm cranks, along with my 76 cm inseam.

Wurm
09-17-05, 09:42 PM
Here's a new signature for you.

"If you ripoff your neighbor and steal his stuff, then you're a dirty smelly assfoe."
- TheDTrainite Proverb

WTF? :rolleyes:

daytonian
09-17-05, 09:58 PM
Your $160 light chief.

Maelstrom
09-17-05, 10:03 PM
WTF? :rolleyes:

Before this gets out of hand. (this includes to those members who are trying to antagonize with no proof and only one side of the story) I would ask you to check your pms. and check this thread

http://www.bikeforums.net/showthread.php?t=139335

TheDTrain
09-17-05, 10:17 PM
I am only stating a proverb made up by me for the benefit of all people viewing this thread and not targeted at any individual. The meaning of the proverb is up for interpretation and has no conotated meanings of any kind. What your idea or opinion is of the proverb is yours and not necessarily the truth or what I mean. All opinions expressed are that of my own and of my own transgression, but I hold no responsibilities for what you may think of my posts or how you respond to them.

Good day.