ok, so i got a coker 6 months ago. I got pretty good at riding. Im thinking about shorter cranks.
what length should i go for? what are the pro’s and con’s of certian lengths? brands I should consider? is it much harder to turn and mount?
The opening post of the thread ‘elementary ballistics’ outlines my special interest in this subject ;0)
The standard Coker cranks are about 150 mm long. They have a double bend in them so that the pedals are further out from the hub than they need to be.
Advantages: plenty of leverage (due to the length) and less chance of catching the crank with the welt of your shoe if you mount clumsily.
Disadvantages: as you rev faster, it is difficult to keep it smooth (due to the length) and the extra width can cause some side to side oscillation.
I put some 127 mm cranks on (5 inches instead of 6, so about 17% shorter).
I have found mounting on flat smooth ground no more difficult. This may be partly because I am used to riding my 20 with 127s, so my feet know where to look for the pedal.
Starting to roll is more difficult, as is coming to a halt from speed.
Even when not trying too hard, the shorter cranks allow you to rev higher, so your cruising speed is a bit faster. At a guess, I’d say about 17% faster. It is noticeable. However, there is a penalty in that you need to apply more force to the shorter lever, so it is a bit harder work. Inclines require more effort, and declines are a bit more alarming.
You do lose out on fine control, both at low speed and when adjusting speed. The flywheel effect takes over and you can feel like you are riding by kind consent of the Coker, and that consent may be withdrawn at any moment.
On the whole, 127s are a reasonable choice for the Coker.
As for anything shorter? I’ve just put 110s on my 20 and they feel ridiculously short. Not difficult to push, but the foot movement is so slight that it feels almost comical. This feeling will wear off. I would suggest two things:
-
If you’re going onto cranks shorter than about 125, try them for a while on a smaller wheel, to get used to the feel of the cranks.
-
Only go for very short cranks if speed is more important than versatility, and if you are prepared to have some nasty falls - however good you are. (I think Roger from Unicycle.uk.com broke his wrist riding with very short cranks on a Coker.)
Have fun, though.
As for the second question about quality. I boldly assume you won’t be hopping, jumping or dropping, so any reasoonable pair will do. I transferred the standard ones from my Nimbus II.
Nick,
What kind of riding will you be doing?
If you’re commuting to class in traffic/people I wouldn’t go any shorter than 5" cranks.
At the risk of mentioning my ride across Iowa again… two of us (myself included) used the 110 mm (4.3") black Bicycle Euros for the ride. My cousin used bent, cheapo 5" cranks. He definitely didn’t have a problem keeping up, despite the longer cranks. I’m inclined to say that you can still cover distance quickly with 5" cranks, but I still prefer my 4.3" cranks.
Re: coker cranks
On Sun, 15 Sep 2002 04:03:32 -0500, Mikefule
<Mikefule.b0kuz@timelimit.unicyclist.com> wrote:
>(I think Roger from Unicycle.uk.com broke his wrist
>riding with very short cranks on a Coker.)
This is even printed on the order confirmation form if you order
Harbinger Extreme Gloves through <www.unicycle.uk.com>.
Klaas Bil
If you had this signature, I have forged it.
I’ve been riding my Coker a couple of years now, and have tried several different lengths/brands of cranks. I really enjoy the smoothness using Semcycle 127mm cranks…problem is, my roads around here are rough and hilly, and i find that the downhills are just a little too hard for me with the shorter cranks. It really depends on where you are riding and what you want to do with it. My compromise for my riding style has been to go back to 150mm cranks, i’m currently using the Odyssey Black Widows…i like the narrow spacing with the straight cranks, it smooths me out a little bit compared to the stock cranks on the Coker.
Chuck
Re: coker cranks
Mikefule.b0kuz@timelimit.unicyclist.com writes:
>The standard Coker cranks are about 150 mm long. They have a double
>bend in them so that the pedals are further out from the hub than they
>need to be.
>
>Advantages: plenty of leverage (due to the length) and less chance of
>catching the crank with the welt of your shoe if you mount clumsily.
>
>Disadvantages: as you rev faster, it is difficult to keep it smooth
>(due to the length) and the extra width can cause some side to side
>oscillation.
So far I totally agree with Mike. I hated having those flanged-out cranks
and couldn’t change 'em fast enough.
>
>I put some 127 mm cranks on (5 inches instead of 6, so about 17%
>shorter).
>
>I have found mounting on flat smooth ground no more difficult. This may
>be partly because I am used to riding my 20 with 127s, so my feet know
>where to look for the pedal.
But this is minor compared with what Mike mentions next – that greater
force is required to start the beast (or turn, or stop), so that’s what
makes different cranks harder, more than just an inch difference in where
the pedals end up.
>
>
>Starting to roll is more difficult, as is coming to a halt from speed.
Turns, too.
>
>
>Even when not trying too hard, the shorter cranks allow you to rev
>higher, so your cruising speed is a bit faster. At a guess, I’d say
>about 17% faster. It is noticeable. However, there is a penalty in
>that you need to apply more force to the shorter lever, so it is a bit
>harder work. Inclines require more effort, and declines are a bit more
>alarming.
>
>You do lose out on fine control, both at low speed and when adjusting
>speed. The flywheel effect takes over and you can feel like you are
>riding by kind consent of the Coker, and that consent may be withdrawn
>at any moment.
I always equate it with driving a big rig. You can’t drive a truck like
you would a Volkswagon Beetle. You REALLY need to think in advance of any
stops or turns at speed.
>
>On the whole, 127s are a reasonable choice for the Coker.
Well, probably for most people (including me), but I use 110s (4.3").
>
>
>As for anything shorter? I’ve just put 110s on my 20 and they feel
>ridiculously short. Not difficult to push, but the foot movement is so
>slight that it feels almost comical.
The feeling wears off as several things happen (in this order):
- You get used to it. Like braces. In the case of Coker riding, I’d say
it takes about 50 miles of riding before a good rider gets totally
accustomed to smaller cranks. - Your balance improves. This makes uphills easier, and it makes riding
in general safer and even faster. - You get better at certain tricks necessitated by the shorter cranks.
For instance, I ride up nasty hills in a way similar to the way a hiker
goes up a steep hill, literally stopping and starting. This is completely
dependent on my improved balance and strength… - As mentioned, your leg strength improves. Then stopping and turning are
easier anyway.
> This feeling will wear off. I
>would suggest two things:
>
>1) If you’re going onto cranks shorter than about 125, try them for a
>while on a smaller wheel, to get used to the feel of the cranks.
I can’t imagine that this is necessary for most riders. But I could be
wrong. I certainly never tried it OR felt the need to do so. Interesting
concept, tho.
>
>2) Only go for very short cranks if speed is more important than
>versatility, and if you are prepared to have some nasty falls - however
>good you are. (I think Roger from Unicycle.uk.com broke his wrist
>riding with very short cranks on a Coker.)
Well, I certainly HAVE had more UPDs since switching down to 110s, and I
am sure that at least a few of them were due to the tiny crank size. But I
am proud to say that I had no UPDs at all on my Century ride, suggesting
that when one is paying close att’n to the road, UPDs are almost
non-existent.
>
>–
>Mikefule - Roland Hope School of Unicycling
>
David Stone
Co-founder, Unatics of NY
Re: coker cranks
I think someone fitted 50mm cranks to Roger’s Coker
at Red Bull last year, while he was sleeping. Not
recommended…