Shorter cranks

LawmanMtb

Member
Aug 15, 2018
142
49
Wigan
who has fitted shorter cranks to their Merida and what lengths did you go for? i have 175mm fitted as standard and am thinking of going to either 165mm or even 160mm, the bike is a Large and im 6'0 .... has anyone done this? if so what is your thoughts? Cheers :)
 

Bonz

Member
Jul 2, 2018
141
99
New Zealand
who has fitted shorter cranks to their Merida and what lengths did you go for? i have 175mm fitted as standard and am thinking of going to either 165mm or even 160mm, the bike is a Large and im 6'0 .... has anyone done this? if so what is your thoughts? Cheers :)
I have the Miranda 155’s which have been great but I’m only 5’7.
You would probably get away with the Shimano 165’s.
I got too many pedal strikes with the 175’s, mostly due to my lack of skill.
There is a lot of info within this forum on this topic. Try a search on shorter cranks or Miranda.
 

HORSPWR

E*POWAH Master
May 23, 2019
853
679
Alice Springs, Australia
I have the Miranda 155’s which have been great but I’m only 5’7.
You would probably get away with the Shimano 165’s.
I got too many pedal strikes with the 175’s, mostly due to my lack of skill.
There is a lot of info within this forum on this topic. Try a search on shorter cranks or Miranda.
I suppose if you’ve got a motor then you can have any length you like but if you retain a reasonable length then you can probably use a lower level of assistance more often and extend your battery life.
 

OlaGB

Member
Subscriber
Mar 19, 2019
78
61
Norway
I’m the exact same height, where did you get the 155s from. I’d consider 160 or 165 maybe, do you notice any extra effort with the 155s?

Miranda directly.

No, didnt notice any effort change. Barely noticed they where shorter at all even on first test.

Would be ok with 150mm as well, but no need to. 155mm clears very rough terrain just perfect for me.
 

steve_sordy

Wedding Crasher
Nov 5, 2018
8,390
8,620
Lincolnshire, UK
Going from 175 to 160 cranks will mean that for a given foot pressure you will be applying nearly 9% less torque. So if you want to do the same things on the bike as before and at the same speed, your motor will have to make up the lost 9%. I'm relatively new to the emtb lark, but it's a pretty good guess that this will mean that your range will reduce by almost 9%.
 

OlaGB

Member
Subscriber
Mar 19, 2019
78
61
Norway
Going from 175 to 160 cranks will mean that for a given foot pressure you will be applying nearly 9% less torque. So if you want to do the same things on the bike as before and at the same speed, your motor will have to make up the lost 9%. I'm relatively new to the emtb lark, but it's a pretty good guess that this will mean that your range will reduce by almost 9%.

Perhaps on the calculator, but i didnt notice any range reduction.
 

OlaGB

Member
Subscriber
Mar 19, 2019
78
61
Norway
As a famous Scottish engineer once said "Ye canna beat the laws o' physics Cap'n!" :LOL:

But you can think youre way out of any kind of fun.

I did a 45km test before and after, hard trail ride. Didnt notice any difference, even though i know its there to some level.

The stock cranks are way to long for any rough terrain, and well worth the change.
 

flash

E*POWAH Elite World Champion
Patreon
Nov 24, 2018
1,050
986
Wamberal, NSW Australia
I changed my stock 170’s for 155’s and then tried 165’s. The 165’s were fine until I put 2.6/2.5 tyres on. I’m putting the 155’s back on.

Gordon
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
13,792
20,481
Brittany, France
I put the Miranda 150's on (all they had in stock on that day for some reason). I'm 178cm.

For the first 5 minutes it felt like I was turning my legs in tiny tiny little circles - I think this was psychological. Once I was out on the trails I didn't notice any difference, except for the huge reduction in pedal strikes (caused mainly by lack of ability).

Didn't notice any change in battery life, found it easier and more natural to pick a slightly higher cadence and my times consistently improved going up and down hill.

I've let other emtb'ers and mtb'ers try the bike and not mentioned the short cranks and no ones noticed or made mention of it.
 

7869hodgy

Well-known member
Jul 15, 2020
395
627
Reading
I’ve swapped from 165 Praxis to 152 Miranda as I had a major off 4 weeks ago and bent the left crank.

Only done 10 miles but they seem fine and have posted some faster times on Strava.

Cadence increase isn’t a problem for me in fact I think it suits my body geometry.
 

RoJo

Active member
Apr 24, 2019
203
174
Surrey
People think they might lose torque with shorter cranks but it is a very complex issue. Firstly cadence will naturally increase because you match foot tangential velocity. Secondly it might suit your physiology better.
Also when doing a technical climb on an eBike if a shorter crank means that you can continue to pedal over rocks/stumps then you will clearly do better than "more torque" put down sporadically.

Needless to say I'm a massive fan of the 165mm xt cranks I fitted. Combined with a 180mm fork I have boat loads of clearance and it's really liberating.


.
 

Ozzie

Member
Nov 10, 2019
14
8
Newcastle Australia
Can anyone tell me where I can get hold of some shorter crank arms. I'm after a set of 155mm cranks, Miranda appear to be out of stock plus I live in Oz and their distributor here has shut down. I'm just wondering if there are any other providers as I can't find anything that is compatible with Shimano from other sources like , CRC, Wiggle, Merlin, ebay etc
 

HORSPWR

E*POWAH Master
May 23, 2019
853
679
Alice Springs, Australia
Can anyone tell me where I can get hold of some shorter crank arms. I'm after a set of 155mm cranks, Miranda appear to be out of stock plus I live in Oz and their distributor here has shut down. I'm just wondering if there are any other providers as I can't find anything that is compatible with Shimano from other sources like , CRC, Wiggle, Merlin, ebay etc
I ordered some directly from the manufactures website, they're not usually out of stock for long and they arrive really fast as they use Fedex to send them.
 

Tonycube

Active member
Apr 30, 2020
100
59
South Wales
Hello everyone.
I managed to buy from a fellow member on here a pair of hope 155mm cranks and took the 165mm e13 cranks off.
Did a first 20 mile ride with them.
Did not notice that you are pedalling smaller circles.
did notice that i had to raise the seat post by the 10mm difference in the crank lengths.
regarding the difference in leverage through the cranks i noticed no difference and lastly no difference in battery range also.
PS no pedal strikes now and i can pedal through corners and tech sections.
Hope this helps from Tony.
 

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