Cranks

Recumbents and all feet forward machines

Cranks

Postby Rowley Runner » Wed Feb 08, 2012 4:49 pm

Will sticking a "normal size" crank make a big difference? Currently my lizard has a 155mm crank with a compact MTB spider which means as far as I am aware the biggest chain ring I can get is 48t. I am after a taller gear would fitting a 175mm road bike crank (hence the ability to fit bigger chain rings) be a bad idea?
Bents for La Tour
User avatar
Rowley Runner
 
Posts: 90
Joined: Thu Apr 15, 2010 12:28 am

by BNA » Wed Feb 08, 2012 5:31 pm

BNA
 

Re: Cranks

Postby John Lewis » Wed Feb 08, 2012 5:31 pm

Will it cause hard interference between the pedal/crank and the front wheel ?
If it does it would not be a good idea.
It is possible to make your own chain ring.
Have a look here. Plenty of people have made them.

http://www.fleettrikes.com/giles%20puck ... ulator.htm

John
John Lewis
 
Posts: 1177
Joined: Tue Oct 02, 2007 7:12 pm
Location: Albany. 400km South of Perth

Re: Cranks

Postby Baalzamon » Wed Feb 08, 2012 6:05 pm

Well if you do jump to 175mm cranks, shoot me a pm as I have a spare pair of 175mm FSA tempo square taper cranks that have seen 2km. I've gone down to 145mm cranks myself.
Masi Speciale CX 2008 - Brooks B17 special saddle, Garmin Edge 810
Image
Baalzamon
 
Posts: 4609
Joined: Mon Mar 12, 2007 1:23 pm
Location: Yangebup

Re: Cranks

Postby just4tehhalibut » Thu Feb 09, 2012 5:19 am

Rowley Runner wrote:Will sticking a "normal size" crank make a big difference?

Depends, as said above, on what you ride and if there are heel strike issues. Also your height or dimensions. I'm 182cm and have been told that for my leg length a 172.5mm crank is suitable. On my road bikes I ride 170-175 but on my Bacchetta recumbent bike I changed to 165mm and found the pedalling better, the heel strike gone. Of course on my trike I like to crank a dinnerplate-sized chainring so 175s are good, 165s would just frustrate.

Crank length has been discussed at great length on other recumbent forums, I've noticed of recent on the Bacchetta forum lots of references about people trying a shorter (than road) crank, found it good but after a year moved back to the old cranks as they were missing on power. This is not why I only went from 170 to 165 on the Bacchetta, I felt that a drop to 155 or lower was too great and that my evaluation of the new set up would be lost in trying to learn what would essentially be new, not slightly modified, equipment, plus the loss of performance from becoming fully committed to being a spinner after years of power-grinding. Others who have ridden on 145-155mm cranks for some time might comment on if the changeover meant a change in pedalling technique or gears as well?

If your recumbent is new learn the bike first before you make a change like this, and keep your old cranks in case you want to swap back later (unless you've started out with a bike fitted with the wrong size cranks, as I suspect occurred for Baalzamon).
just4tehhalibut
 
Posts: 863
Joined: Thu Oct 23, 2008 4:02 am
Location: Spearwood, WA

Re: Cranks

Postby Poiter » Thu Feb 09, 2012 9:23 am

You can fit larger chainrings on a 110 PCD crank.
Trisled has 65 tooth for $85
http://www.trisled.com.au/online-shop.asp
Pete
User avatar
Poiter
 
Posts: 243
Joined: Wed Mar 26, 2008 6:18 pm
Location: Canberra

Cranks

Postby Rowley Runner » Thu Feb 09, 2012 11:02 pm

Thanks for the tips. I think I need to work on my riding style. I am use to standing up and grinding in a big gear. Spinning seems to be the way to go on a bent. Just put some SPDs on for today's commute and that has made a world of difference, much more efficient.
Bents for La Tour
User avatar
Rowley Runner
 
Posts: 90
Joined: Thu Apr 15, 2010 12:28 am

Re: Cranks

Postby ColinOldnCranky » Thu Feb 09, 2012 11:53 pm

Sorry. I read the subject title and thought that maybe you were talking about me. :mrgreen:

I gotta go and kick the dog now so I'll just quietly leave.
Unchain yourself - Ride a unicycle .Image
User avatar
ColinOldnCranky
 
Posts: 4697
Joined: Fri Feb 27, 2009 3:58 pm

Re: Cranks

Postby just4tehhalibut » Fri Feb 10, 2012 1:58 am

ColinOldnCranky wrote:... thought that maybe you were talking about me.

I tell you what, you convert your unicycle into a recumbent and you can stay. (I've often wondered what that'd look like).
just4tehhalibut
 
Posts: 863
Joined: Thu Oct 23, 2008 4:02 am
Location: Spearwood, WA

Re: Cranks

Postby ColinOldnCranky » Fri Feb 10, 2012 6:57 am

just4tehhalibut wrote:
ColinOldnCranky wrote:... thought that maybe you were talking about me.

I tell you what, you convert your unicycle into a recumbent and you can stay. (I've often wondered what that'd look like).

Image
Unchain yourself - Ride a unicycle .Image
User avatar
ColinOldnCranky
 
Posts: 4697
Joined: Fri Feb 27, 2009 3:58 pm


Return to Recumbents

Who is online

Users browsing this forum: No registered users



Popular Bike Shops
Torpedo 7 Torpedo7 AU
Ground Effect Ground Effect NZ
Chain Reaction Cycles CRC UK
Wiggle Wiggle UK
Ebay Ebay AU

“Bicycles BNA Twitter
“Bicycles BNA Facebook
“Google+ BNA Google+
“Bicycles BNA Newsletter

> FREE BNA Stickers
> BNA Cycling Kit