|
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
Mitigating crank failure
Russell Seaton writes:
Phil Lee used the term "invariably". The online dictionary says invariably means "Not changing or subject to change; constant". From the pictures above you can easily deduce that shoe rubbing is not a constant/invariable beginning of cranks cracking. I think a reading of the FAQ and Brandt's postings about cranks cracking would provide a better cause and understanding than shoe rubbing. These pictures are the ones found posted on this forum. I am sure there are other pictures on the web showing all manner of crank failures. There are more at: http://pardo.net/bike/pic/fail-001/ Jobst Brandt |
Ads |
#12
|
|||
|
|||
Mitigating crank failure
|
#14
|
|||
|
|||
Mitigating crank failure
john wrote: I'm surprised at how little hollow there is in the "Hollow Tech". That crank is 10% hollow and 90% crank. Hardly worth the effort, or expense. Is this typical? I think just at that location of the arm it essentally solid. It is much more hollow in the middle. |
#15
|
|||
|
|||
Mitigating crank failure
|
#16
|
|||
|
|||
Mitigating crank failure
On Wed, 09 Nov 2005 12:04:01 -0500, dvt wrote:
Adding thickness to either side (shoe or crank) will just make shoe rub more annoying. The only solution I'd consider is an increase in the spacing. But many don't like a wider Q factor, so I guess we'd be stuck with the lowest profile cranks available. Maybe the angle of the arm could be adjusted, too. The shape of different crankarms will make a difference in shoe contacting the crank. Placement of the cleat in the shoe and type of shoe can change distance between shoe and crankarm. Type of pedal makes a difference. Shimano MTB pedals position the shoe a bit further from the crankarm than road pedals. Washers between pedal and crankarm move shoe away from arm. Wider Q doesn't necessarily put shoe or ankle away from arm. Plastic laminating tape on the crankarm protects it. I've got big feet and don't like my cranks getting cosmetically marked. I haven't had a crankarm fail because of rub...yet. |
#17
|
|||
|
|||
Mitigating crank failure
wrote in message ... Russell Seaton writes: Phil Lee used the term "invariably". The online dictionary says invariably means "Not changing or subject to change; constant". From the pictures above you can easily deduce that shoe rubbing is not a constant/invariable beginning of cranks cracking. I think a reading of the FAQ and Brandt's postings about cranks cracking would provide a better cause and understanding than shoe rubbing. These pictures are the ones found posted on this forum. I am sure there are other pictures on the web showing all manner of crank failures. There are more at: http://pardo.net/bike/pic/fail-001/ So, is shoe rub (which causes polishing rather than scratches) capable of causing or accelerating crank failure? -- Jay Beattie. |
#18
|
|||
|
|||
Mitigating crank failure
On 9 Nov 2005 10:17:26 -0800, wrote:
dvt wrote: wrote: Phil, Squid-in-Training wrote: Crack propagation on cranks breaking at midsection is invariably started with shoe rub. Phil Squid used the term "invariably". The online dictionary says invariably means "Not changing or subject to change; constant". From the pictures above you can easily deduce that shoe rubbing is not a constant/invariable beginning of crankset cracking. I think a reading No, you really can't. On all the cranks *breaking at the midsection* you found, visible shoe rubbing was present around the crack. Jasper |
#19
|
|||
|
|||
Mitigating crank failure
after the last crank failure i rotored over to the LBS and asked for
the crank box paleontology-worth the study-crank design!!! picked out 4 and threw em in the bottom of toolbox 3 now i pray the CR stays also see Crank saver in archives |
#20
|
|||
|
|||
Mitigating crank failure
jbuch wrote:
Phil, Squid-in-Training wrote: With another customer's broken crank coming in this week for replacement, I've been thinking... is there a better solution to all these broken cranks? Crack propagation on cranks breaking at midsection is invariably started with shoe rub. Since nobody would pay for cranks with a "shoe rub shim" on it, why not sell shoes that have felt/terrycloth/foam bits that cover the inside of the ankle? This would be unobtrusive, could be dyed the color of the shoe, and cut down on deeper cuts in the metal that would start cracks. These shoes could be sold to the radonneur/brevet/messenger/commuter/old fart group of riders that would appreciate such a feature. Thoughts? If you are really into "high performaqnce components", I would suggest that you remove the cranks and have them coated with synthetic diamond or "diamond-like carbon" to increase wear resistance. There are other hard wear resistant coatings that could be applied for the lower cost or second quality level biking components. you'd better not mention wear resistant anodizing on this group.... |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Cranks that can handle a wide range of chain rings | Chris M | Techniques | 17 | March 9th 05 03:56 AM |
Stripped crank arm | Steve | Techniques | 14 | May 21st 04 06:45 PM |
Longer crankarms | Jiyang Chen | Racing | 129 | March 18th 04 12:37 PM |
Profile Crank Problem | fluffinator007 | Unicycling | 25 | February 24th 04 04:54 AM |
Adjustable crank idea | onewheeldave | Unicycling | 93 | February 13th 04 10:34 PM |