|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Crank ID req. on Singlespeed CX bike
Nice singlespeed CX bike here
http://img149.imagevenue.com/img.php...22_9 01lo.jpg but what are the cranks? Look BMX-ish, and as far as I can see they're a T-section beam. Odd. Kinky Cowboy* *Batteries not included May contain traces of nuts Your milage may vary ** Posted from http://www.teranews.com ** |
Ads |
#2
|
|||
|
|||
Crank ID req. on Singlespeed CX bike
Kinky Cowboy wrote:
Nice singlespeed CX bike here http://img149.imagevenue.com/img.php...istina6_04_06L... but what are the cranks? Look BMX-ish, and as far as I can see they're a T-section beam. Odd. Those are taper-fitted cranks, not much like the BMX cranks I'm familiar with. They look more reminiscent of CNC-era mountain bike stuff. Perhaps she used alkali to strip off the Rasta tricolor anodizing. Structurally speaking, it would probably be better to load the web in tension and the flat in compression. If she gets a left-hand drive rear wheel, she'll be all sorted out. Chalo |
#3
|
|||
|
|||
Crank ID req. on Singlespeed CX bike
On Tue, 22 Apr 2008 16:11:57 -0700 (PDT), Chalo
wrote: Kinky Cowboy wrote: Nice singlespeed CX bike here http://img149.imagevenue.com/img.php...istina6_04_06L... but what are the cranks? Look BMX-ish, and as far as I can see they're a T-section beam. Odd. Those are taper-fitted cranks, not much like the BMX cranks I'm familiar with. They look more reminiscent of CNC-era mountain bike stuff. BMX-ish in the sense of junior BMX kit, where aluminium alloy square taper cranks are common. The fact that the spider is a: separate and b: looks familiar from something I've seen on a BMX site also suggests BMX rather than MTB origin. The T section might be the wrong way round, but the mystery is why it's a T instead of an H in the first place. The even bigger mystery is why all cranks aren't tubular, like the BMX CroMo cranks you're familiar with, as a crank is a torsion bar, not a beam :-) Kinky Cowboy* *Batteries not included May contain traces of nuts Your milage may vary ** Posted from http://www.teranews.com ** |
#4
|
|||
|
|||
Crank ID req. on Singlespeed CX bike
"Kinky Cowboy" a écrit:
Nice singlespeed CX bike here http://img149.imagevenue.com/img.php...22_9 01lo.jpg but what are the cranks? XLR8?: http://www.retrobike.co.uk/forum/fil...8crank_631.jpg http://cgi.ebay.com/ws/eBayISAPI.dll...m=220227665875 James Thomson |
#5
|
|||
|
|||
Crank ID req. on Singlespeed CX bike
On Wed, 21 May 2008 19:17:24 +0200, "James Thomson"
wrote: "Kinky Cowboy" a ?crit: Nice singlespeed CX bike here http://img149.imagevenue.com/img.php...22_9 01lo.jpg but what are the cranks? XLR8?: http://www.retrobike.co.uk/forum/fil...8crank_631.jpg http://cgi.ebay.com/ws/eBayISAPI.dll...m=220227665875 James Thomson That would seem to be it. Thanks. Kinky Cowboy* *Batteries not included May contain traces of nuts Your milage may vary ** Posted from http://www.teranews.com ** |
#6
|
|||
|
|||
Crank ID req. on Singlespeed CX bike
someone wrote:
Nice singlespeed CX bike here http://img149.imagevenue.com/img.php...22_9 01lo.jpg but what are the cranks? XLR8?: http://www.retrobike.co.uk/forum/fil...8crank_631.jpg There is another excellent example of a finely finished product designed by someone who doesn't understand the function. The largest load cranks transmit is torsion from the outboard position of the foot on the pedal, although in a side view is not apparent. The crank is a lever that is loaded off axis so that its shaft has far higher (about 5x) torsional stress than it has in lever bending. Torsional strength is given by the largest inscribed circular cross section of the lever, which in this model is tiny, all the flat and flashy part being unstressed. http://cgi.ebay.com/ws/eBayISAPI.dll...m=220227665875 That would seem to be it. Thanks. This has been a design problem that has caused many crank failures and ultimately got Campagnolo to get rid of the vanity groove on the outside of their cranks that cost them durability. Jobst Brandt |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
French cottered crank singlespeed conversion? | Luigi de Guzman | General | 16 | February 11th 06 11:36 AM |
"Compact Double Crank" = "Touring Bike Crank" | Robert Perkins | Techniques | 10 | June 3rd 05 04:35 AM |
WTB: Large, 57cm, 19-20" singlespeed bike | Philip W. Moore, Jr. | Marketplace | 0 | May 26th 05 01:54 AM |
silstar crank, old bike | [email protected] | Techniques | 15 | May 8th 05 12:06 AM |
mountain bike or fixed gear singlespeed:thanks everyone | Brink | General | 1 | July 29th 03 04:44 AM |