What the F diffrence !!!

[hagar]

could someone please explain what the diffrence is between the lengths in cranks like a 172 and a 175 mm ok 3mm i know that but would the one give you more power that the other or what ???

 

Thanks

hagar2009-09-10 11:50:20

[hagar]

35 views and not one answer

[DownhillingKing]

Think back to the days when you were in school a longer lever makes it easier to move something right I'am guessing it is the same sort of thing

[XTC OKE]

i dunno

[EigerSA]

I can't see how crank length would make any real impact on your ability to pedal harder, like longer length having more of a lever effect or something like that, mostly because you got gears! Any benefits from crank length would be so small as to be happily ignored. If anything I would say that crank length just helps in setting up the bike. Since all manufacturers have their own sizing guide, I guess it's just one more thing you could take advantage of in order to perfect your fit... nothing more!

[Racer X]

Well the theory is that shorter cranks are suited to riders with higher candences while the longer cranks are suited to riders who prefer a slower candence and harder geards. Height also plays a role, ie. Taller - longer cranks and vice versa if you're 2 ft 1.

 

Again that's theory, never seen any evidence to support it though. 

[SwissVan]

could someone please explain what the diffrence is between the lengths in cranks like a 172 and a 175 mm ok 3mm i know that but would the one give you more power that the other or what ???

 

Thanks

 

 Actually 2.5mm.... 172 cranks are usually 172.5

 

Only the engine room can give you more power.

 

Beam me and my coat up Scotty

 

 

[crasher]

If you take it in the contex of a car engine then you crank lentgh would be the same as the stroke of your crankshaft.

 

If you want more torque (turning power) you have a longer stoke

 

If you want more speed/RPM you would have a shorter stroke

 

So I would hazard a guess that the longer yor crank arm the greater torque you will generate

 

Go shorter and you would have less torque but more rpm/pedal speed.

 

thats my guess

[DownhillingKing]

O so I was sort of right then

[Racer X]

If you take it in the contex of a car engine then you crank lentgh would be the same as the stroke of your crankshaft.

 

If you want more torque (turning power) you have a longer stoke

 

If you want more speed/RPM you would have a shorter stroke

 

So I would hazard a guess that the longer yor crank arm the greater torque you will generate

 

Go shorter and you would have less torque but more rpm/pedal speed.

 

thats my guess

 

So in essence we concur.

[thenoodle]

The guys with longer cranks have to ride 3mm further per leg rotation. So lets say you ride 10km in 30 minutes @ 100rpm with 175mm cranks. You will on average ride 9 metres further than someone with 172mm cranks. Now there is enough bullsh*t to fertilize your spring gardens! 

[hagar]

aaaaah thanks guys so it really does not make that much diffrence to a novice like me !!! thanks swissvan as you say its the engine room !!! looks like the boffins today were not on the hub !!!

[SwissVan]

 

And dont forget ground clearance when cornering, riding ruts, or rocks...., a few mm longer and your pedals are a few mm's closer to the ground.

 

 

[hagar]

The guys with longer cranks have to ride 3mm further per leg rotation. So lets say you ride 10km in 30 minutes @ 100rpm with 175mm cranks. You will on average ride 9 metres further than someone with 172mm cranks. Now there is enough bullsh*t to fertilize your spring gardens! 

 could me the diffrence from me being on the poduim or not !!! now that is bullsh*t for you  

 

thanks

[Snidge]

The way I see it, the weaker your legs then use a shorter crank to get more power from the revs. But if you have strong leg power I can see the benefit of using longer cranks.

It all depends on how high your cadence is. Im no expert but thats my opinion.

[EigerSA]

 

What!? How can the length of the crank make any difference? Cadence has got to do with your personal power... it's gonna make no difference whatsoever what crank length I put on my bike, I'm not going to hit the same cadence as Lance Armstrong (that's where your gears come into play)! The only effect a varying crank will make is help the fit on the bike better for the individual rider, if you feel better with a longer crank, and essentially a longer circumference of stroke, then good for you! You then either be raising or lowering your seat in relation to the crank length.

 

EigerSA2009-09-10 12:27:49