Re: [yak] Digest for yak@bikefriday.com - 7 updates in 1 topic

[robert clark]

With a shorter crank the pedal BDC is higher, so, you would move the saddle height Up...

On Thu, Sep 18, 2025 at 6:57 PM <y...@bikefriday.com> wrote:

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• shorter cranks - 7 Updates

shorter cranks

Sue Reinert <reine...@gmail.com>: Sep 18 07:12AM -0700 If I were to install shorter cranks on my 2018 Pocket Llama what other adjustments would I need to make? Current cranks are size 170 and I am getting shorter as I age. The Llama frame is small (top tube 48 cm).

Eric Daume <eric...@gmail.com>: Sep 18 10:43AM -0400 If your body is staying the same, shorter cranks need a taller seat height to get the same leg extension. Then you might need a taller bar height to keep the seat to bar relationship the same.   Smaller cranks will give you less leverage, so your gearing might feel harder. But IME, this effect is really minor.   Eric

John S. Allen <jsa...@bikexprt.com>: Sep 18 11:40AM -0400 I am getting shorter too, and the change is in my spine, not my legs. My trousers still fit. The main adjustment that I think you may want to make is to get the handlebar closer.   Sent from my iPhone   On Sep 18, 2025, at 10:43 AM, Eric Daume <eric...@gmail.com> wrote:   If your body is staying the same, shorter cranks need a taller seat height to get the same leg extension. Then you might need a taller bar height to keep the seat to bar relationship the same.   Smaller cranks will give you less leverage, so your gearing might feel harder. But IME, this effect is really minor.   Eric   On Thursday, September 18, 2025, Sue Reinert <reine...@gmail.com> wrote:   If I were to install shorter cranks on my 2018 Pocket Llama what other adjustments would I need to make? Current cranks are size 170 and I am getting shorter as I age. The Llama frame is small (top tube 48 cm).   --   another great conversation from the Bike Friday Yak!   ---   You received this message because you are subscribed to the Google Groups "Bike Friday Yak!" group.   To unsubscribe from this group and stop receiving emails from it, send an email to yak+uns...@bikefriday.com.   To view this discussion visit https://groups.google.com/a/bikefriday.com/d/msgid/yak/c529157e-c827-4c26-8983-257280bf2e9fn%40bikefriday.com.   --   another great conversation from the Bike Friday Yak!   ---   You received this message because you are subscribed to the Google Groups "Bike Friday Yak!" group.   To unsubscribe from this group and stop receiving emails from it, send an email to yak+uns...@bikefriday.com.   To view this discussion visit https://groups.google.com/a/bikefriday.com/d/msgid/yak/CAHFNW5BThsnsusM9mB0G9ddNhdz-_KTOtuUYfyu7c76kt4B-jQ%40mail.gmail.com.

John S. Allen <jsa...@bikexprt.com>: Sep 18 11:43AM -0400 But also shorter cranks might be a good idea anyway. The tendency with cranks is one-size-fits-all, and that works fine for me as an average sized male.   Sent from my iPhone   On Sep 18, 2025, at 11:40 AM, John S. Allen <jsa...@bikexprt.com> wrote:    I am getting shorter too, and the change is in my spine, not my legs. My trousers still fit. The main adjustment that I think you may want to make is to get the handlebar closer.   Sent from my iPhone   On Sep 18, 2025, at 10:43 AM, Eric Daume <eric...@gmail.com> wrote:   If your body is staying the same, shorter cranks need a taller seat height to get the same leg extension. Then you might need a taller bar height to keep the seat to bar relationship the same.   Smaller cranks will give you less leverage, so your gearing might feel harder. But IME, this effect is really minor.   Eric   On Thursday, September 18, 2025, Sue Reinert <reine...@gmail.com> wrote:   If I were to install shorter cranks on my 2018 Pocket Llama what other adjustments would I need to make? Current cranks are size 170 and I am getting shorter as I age. The Llama frame is small (top tube 48 cm).   --   another great conversation from the Bike Friday Yak!   ---   You received this message because you are subscribed to the Google Groups "Bike Friday Yak!" group.   To unsubscribe from this group and stop receiving emails from it, send an email to yak+uns...@bikefriday.com.   To view this discussion visit https://groups.google.com/a/bikefriday.com/d/msgid/yak/c529157e-c827-4c26-8983-257280bf2e9fn%40bikefriday.com.   --   another great conversation from the Bike Friday Yak!   ---   You received this message because you are subscribed to the Google Groups "Bike Friday Yak!" group.   To unsubscribe from this group and stop receiving emails from it, send an email to yak+uns...@bikefriday.com.   To view this discussion visit https://groups.google.com/a/bikefriday.com/d/msgid/yak/CAHFNW5BThsnsusM9mB0G9ddNhdz-_KTOtuUYfyu7c76kt4B-jQ%40mail.gmail.com.

John Thurston <y...@thurstons.us>: Sep 18 10:25AM -0800 To answer your specific question, I'll echo and amplify what others have said.   If you shorten the crank, you'll want to raise your seat by the difference to maintain your leg extension. If you want to maintain the same height relationship between your saddle and bar, you'll also want to raise your bars by the same amount. So if you replace your 170mm crank with a 165mm, you'll want to raise both the saddle and bar by 5mm.   Raising the seat should be simple. Raising the bars may be more difficult. How difficult depends on what style riser, stem, and bar you have.   Shortening the crank won't change the gear-inch range you have on the bike, but it will reduce the leverage you can supply. You'll have less torque (so climbing in the gears you have may be harder), but (with a little practice) will be able to spin more quickly.   From here on, I'm providing unsolicited observations and suggestions. Take them, or leave them, as you like.   As I have aged, I've changed the configuration my Llama (from the 90s) several times. My legs haven't changed their length much, but I'm a whole lot less flexible than I used to be! I'm still running 170mm cranks (though not the original), but I've had three different stem risers made for it as I've changed. I've also changed my saddle, as my riding position has changed.   Think hard about your body and pedaling needs before you simply swap cranks and expect an significant change in the bike fit. Think about bar height and reach, with respect to your saddle position. Then, if that needs to change, talk to Bike Friday. There was a time when they'd send you a fully adjustable riser/stem for your bike. You'd make changes to it until you had the bars just where you wanted them, and then you'd send it back to Bike Friday. They'd then make a custom riser which put the bars exactly where you wanted them.     -- John Thurston Juneau, Alaska   On 9/18/2025 6:12 AM, Sue Reinert wrote:

Sue Reinert <reine...@gmail.com>: Sep 18 12:07PM -0700 Thanks everyone for your comments, they are very helpful. I haven't decided what to do.   On Thursday, September 18, 2025 at 2:25:53 PM UTC-4 John Thurston wrote:

Phil Hammerslough <phil.ham...@gmail.com>: Sep 18 03:13PM -0400 Being a shorter Bike Friday Family Tandem owner I use a 157 crank. It takes the crankiness out reaching for the impossible! Best, Phil

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[robert clark]

In anothe forum , Because one of the Pros won races and he chose shorter crankarms, they thought 

[robert clark]

that the crank change was responsible for that   If you spin the cranks at a high RPM, 80+ then those few mm  in  difference may please your aesthetics , Will it improve the time trial results? the stopwatch will judge that....

Old man with a variety of crank arm lengths on various bikes .. and @ a rather low cadence it matters little...