I’ve been riding 165mm cranks without any problems for a couple seasons. 2 months ago, I started upping my running mileage from 50mpw to 70mpw and started hating being in the aerobars (maybe due to the decreased flexibilty I had experienced?) I tried raising my bars by 1cm, but it still wasn’t ideal. I decided to switch to 155mm cranks via Origin8 and a 107mm sq taper bottom bracket.
After installing the new crank /bb, I raised my seat 1cm to maintain my saddle height. I left the saddle set back and arm pad stack the same. All I can say is wow, I feel so much better. No change in power ouput, but I can comfortably ride low without the need to come out of the aerobars.
I really love the 155mm cranks. Will I prefer 150mm or 145mm (smallest I can go without losing power as per Jim Martin)?
Ya i dropped 10mm to 165’s and felt a ton better, but i think 155 will be my sweet spot too. Just have been too lazy to switch, or just waiting for nicer cranks to come in that length. I believe there are a few companies where you can order custom sizes now? Glad to hear you found your sweet spot. What a difference a little bit can make in how your entire position can feel.
Clinchers are faster, short cranks are faster, wide is often more aero than skinny, i feel like i’m in some bizarro world. Of course i’m using my early 80’s mentality to compare it too. Just glad i’m not too old to accept change from some really entrenched ideas from the cycling world.
I dunno, I think Mavic’s kona yaw angle data may suggest the wider is more aero than narrow (for wheels) is wrong!
At least, if you are willing to run a narrow tire anyway. So we still have that, maybe!
Ya i dropped 10mm to 165’s and felt a ton better, but i think 155 will be my sweet spot too. Just have been too lazy to switch, or just waiting for nicer cranks to come in that length. I believe there are a few companies where you can order custom sizes now? Glad to hear you found your sweet spot. What a difference a little bit can make in how your entire position can feel.
Clinchers are faster, short cranks are faster, wide is often more aero than skinny, i feel like i’m in some bizarro world. Of course i’m using my early 80’s mentality to compare it too. Just glad i’m not too old to accept change from some really entrenched ideas from the cycling world.
Are you riding with a Powertap power meter or is it just your perception that power is the same?
Thanks for the information.
Hugh
Similar question: How does power vs torque play into the issue of a shorter crank? I would think that since the lever is shorter, one would either have to apply greater power to turn a crank at the same speed or if the same power is applied less maximum torque could be generated. The question becomes how are torque, power and human anatomy related to speed at the rear wheel. Can a physicist explain this to me?
Ya i dropped 10mm to 165’s and felt a ton better, but i think 155 will be my sweet spot too. Just have been too lazy to switch, or just waiting for nicer cranks to come in that length. I believe there are a few companies where you can order custom sizes now? Glad to hear you found your sweet spot. What a difference a little bit can make in how your entire position can feel.
Clinchers are faster, short cranks are faster, wide is often more aero than skinny, i feel like i’m in some bizarro world. Of course i’m using my early 80’s mentality to compare it too. Just glad i’m not too old to accept change from some really entrenched ideas from the cycling world.
John Cobb has some nice cranks available in 145, 155, and 165 in either standard or compact with a good bottom bracket for $300. Rotor 3d + also has a power meter in 155mm.
I may go the John Cobb route once I figure out how short I want to go.
Very tempted to take the plunge and get some 105 165mm crank for $148. Pretty cheap “upgrade” if it allows my to bike stronger while training a high running volume.
I can save my Ultegra cranks that came with the bike for a future 10 speed upgrade of my road bike.
I may go the John Cobb route once I figure out how short I want to go.
In the meantime Stronglight Impact Kid is a cheap way to try short cranks (I have used them for petite riders for many years).
PCD 110 mm
130 / 145 / 150 / 155 mm
Are you riding with a Powertap power meter or is it just your perception that power is the same?
Thanks for the information.
Hugh
Similar question: How does power vs torque play into the issue of a shorter crank? I would think that since the lever is shorter, one would either have to apply greater power to turn a crank at the same speed or if the same power is applied less maximum torque could be generated. The question becomes how are torque, power and human anatomy related to speed at the rear wheel. Can a physicist explain this to me?
Depends on what you’re comfortable with, in terms of spinning whatever gear you run.
If you switch to long cranks, from what I’ve read, people love mashing that with a lower RPM and having positive results. However, if you’re a spinner, you can sit in a smaller gear with the shorter cranks and just spin away. You’re also using a smaller range of muscles due to pedaling in shorter circles; I don’t know how that bit translates to power, though.
I would think that since the lever is shorter, one would either have to apply greater power to turn a crank at the same speed or if the same power is applied less maximum torque could be generated.
That is true. On the flat, one would need to increase cadence to compensate if using shorter crank. On hills, one would need to shift to the next larger cog.
Ya i dropped 10mm to 165’s and felt a ton better, but i think 155 will be my sweet spot too. Just have been too lazy to switch, or just waiting for nicer cranks to come in that length.
Been riding 150s the last year on the TT, and 172s on the road. No problem switching back and forth.
And I can testify that I’ve not lost a bit of power even with 20mm more drop… many data points on the same TT course. I was hoping for an increase, but oh well. And the short cranks feel much better in aero. That may be more important for you poor guys who have to run afterwards.
I’m running old Ultegra octalinks that have been shortened by Bikesmith. That is an option if you don’t want to use BMX cranks.
Do you tend to ride at a higher cadence, or lower cadence? Wondering if those experience loss of power when switching cranks may prefer lower cadence, and thus might want a slightly longer lever.
Interesting, I’ve been looking to drop from my 175s down to 170 or 165 but I’m having trouble finding small cranks with 130 bcd. I don’t want to give up my 130 bcd Osymetric rings because I have been riding and running REALLY well with them.
What is suggested is that you switch to the shorter cranks that do not affect power. My question is whether those preferring lower cadence will experience the power drop sooner than those with higher cadence, while trying shorter and shorter cranks.
On the flat, one would need to increase cadence to compensate if using shorter crank. On hills, one would need to shift to the next larger cog.
Nope… you can push harder, spin faster, or apply force effectively over a greater % of the circle… or a combination of the 3.
In my case my cadence went up ~3% when I switched to cranks that were 13% shorter. I suspect that most of the difference is made up from applying force over a greater % of the circle since more of that circle is now in the range where I can apply force effectively.
I run 165s now and because I have shitty hip flexibility am stuck at my current front end height. I am curious about going even shorter. Out of curiosity how tall are you and what is your inseam?
