170mm cranks on Women Specific Design?

seanpk

Just looking at the Trek Mynx WSD (Women Specific Design) http://www.trekbikes.com/int/en/bikes/m ... untry/mynx and after a bit of digging found it had 170mm cranks on even the smallest frame. They put all that effort into an appropriate standover height and reach and then bale out with a generic crankset!

nicklouse

seanpk wrote:

Just looking at the Trek Mynx WSD (Women Specific Design) http://www.trekbikes.com/int/en/bikes/m ... untry/mynx and after a bit of digging found it had 170mm cranks on even the smallest frame. They put all that effort into an appropriate standover height and reach and then bale out with a generic crankset!

and? what is the issue?

cooldad

I think you'll find most bits are generic. Or should they make tiny shifters for dainty lady fingers as well.
And before anyone calls me a sexist I have tiny dainty fingers as well.

seanpk

nicklouse wrote:

and? what is the issue?

It's pretty well accepted in basic bike setup (driven by simple mechanics and sports science) that significantly shorter legs need shorter cranks or you end up with your knees under your chin when set at a good position on the down stroke - the maths says a 5'0" rider should be down to about a 150 crank. Yeah its not going to be too noticeable on technical stuff but on XC it makes a lot of difference. Shorter riders would also benifit from a lower BB which is going to be a bummer with long cranks as you loose ground clearance. Toe overlap could start being an issue on livelier/short wheelbase frames in smaller sizes with 29s

Basically if you scale down a frame and emphasise its WSD selling point then do it all not just bits of it, the frame tubes probably still have the same gauge as the blokes frames when they could be significantly lighter.

Look at this from Isla Rowntree as a masterclass in appropriate sizing - 11.4kg - http://www.islabikes.co.uk/bike_pages/creig26.html - wouldn't you have loved pne of them when you were 9 ?

cooldad

seanpk wrote:

nicklouse wrote:

and? what is the issue?

Basically if you scale down a frame and emphasise its WSD selling point then do it all not just bits of it, the frame tubes probably still have the same gauge as the blokes frames when they could be significantly lighter.

What happens if it's for a short fat heavy person?
BB height is hardly relevent to height - that's why seat tube length varies.

nicklouse

seanpk wrote:

nicklouse wrote:

and? what is the issue?

It's pretty well accepted in basic bike setup (driven by simple mechanics and sports science) that significantly shorter legs need shorter cranks or you end up with your knees under your chin when set at a good position on the down stroke

and yes that is what they have done fitted short cranks to the WSD versions just like all the mens have 175mm cranks.

150mm cranks right. lets see you get some suitable ones.

yes crank length change is fine on a road bike where you are sat in the same boring position day in and day out just sinning those pedals but on an MTB it has so much less to effect and actualy shorter cranks can be worse as you lose some leverage for the same gear.

so to sum up you are happy that trek have the same length cranks on the mens bikes but not happy that the WSD have the same length cranks (but shorter than the mens)?

benpinnick

Also remember though, crank length effects power too. Go too short and you'll run out of steam pretty quick.

seanpk

benpinnick wrote:

Also remember though, crank length effects power too. Go too short and you'll run out of steam pretty quick.

That's what gears are for - the torque (leverage) generate in your axle is a product of the crank length and the selected gear, 170s are generally fine for ‘average’ blokes but if your legs are significantly shorter then the bio mechanics are messed up. If we accept your argument then you’d be happy with 200mm cranks? But to get the same saddle height relative to the bottom of the stroke your leg at the top of the stroke would be bent to an uncomfortable angle and you’d move to a bigger sprocket for the same torque.

supersonic

On average women have longer legs for a given height then men.

nicklouse

supersonic wrote:

On average women have longer legs for a given height then men.

and on average women are shorter than men.

so the cranks should be the same length as on the mens?

benpinnick

seanpk wrote:

benpinnick wrote:

Also remember though, crank length effects power too. Go too short and you'll run out of steam pretty quick.

If we accept your argument then you’d be happy with 200mm cranks?

No, why would you think that was the logical conclusion to my statement?

benpinnick

supersonic wrote:

On average women have longer legs for a given height then men.

I dont think thats true... I think its .56 of height for men and women. You'd think not, but maybe the body shape makes it look that way.

supersonic

Which would nullify the argument for shorter female cranks (per given frame size) just as much.

But 0.56?! Surely is less than half for most people!

benpinnick

Probably not inside leg, leg is measured from base of foot to hip I think. obviously inside leg is going to be shorter!

Chunkers1980

http://www.youtube.com/watch?v=MTs-HKiOQj8

paul.skibum

If you give a short girl a 150mm crank and the same 2x10 gearing as a fella on his bike but with a 175mm crank I forsee an arguement between the two shortly after they start climbing the first hill. If they both drop to the granny ring for the climb then fella is getting way more bank for his buck for every pedal stroke.

a 170mm crank is a fair compromise - maybe on a very small bike a 165mm could be an option but you dont see it for guys small bikes.

The Rookie

Deore HT2 (as an example) is only available in 170 and 175mm, very few cranks around at 165mm even....

robertpb

Women have longer legs as a percentage of their height and shorter torsos on average.

YeehaaMcgee

benpinnick wrote:

supersonic wrote:

On average women have longer legs for a given height then men.

I dont think thats true...

You may not think it, but it is.
Proportionally shorter bodies, and longer legs (on average, although people do differ).

nicklouse

i still dont know why the OP is pissed. is it too short, too long or that they are all the same?

benpinnick

Actually I think the real issue is that wsd bikes have little real women specifics at all, wsd bikes are barely different to men's. they add a big curve to the top tube for the perceived problem of stand over (which is no worse than on men's bikes) when in reality the underlying geometry is not much different.

Kowalski675

Could be worse - with motorcycle clothing they just make it less protective than the men's stuff, then add some pink, lol.

YeehaaMcgee

benpinnick wrote:

Actually I think the real issue is that wsd bikes have little real women specifics at all, wsd bikes are barely different to men's. they add a big curve to the top tube for the perceived problem of stand over (which is no worse than on men's bikes) when in reality the underlying geometry is not much different.

it does vary by bike manufacturer though. Some have shorter top tubes, some have narrower bars, some have generally lighter duty components, some even go as far as fitting softer springs in the (coil) forks. Almost all of the ones who offer WSD bikes offer at least a female specific saddle.
Some others just put girly graphics on them!