An engineering improvement or a marketing brandshare grab?

[Andre Jute]

Unevenly spaced chainring bolt circle. Honestly.

http://pardo.net/bike/pic/mobi/d.uneven-round-chainring-bolt-patterns/index.html

Have they "improved" it till it no longer works? After all, with evenly spaced bolts, you can rotate the chainring and get a significant increase in the life of the component.

Andre Jute

[Danneaux]

Yeah...no. I saw this first occur in the Dura-Ace stuff for roadies. Bad idea there, bad idea elsewhere. I always "clock" my chainrings around periodically to even out the wear from my power stroke and find it helps; I have managed tremendous chainlife on my old, wide Sugino anodized alu 'rings, but my cruising-gear chainlines are almost dead-straight by careful design of my gearing and the use of a half-step arrangement, thick chainrings, and wide 5-sp or 6-sp chains. My old derailleur drivetrains have led easy lives.

This, though...this is absurd.

I do recall at least one subcontracted name-brand crank from the late 1980s or early 1990s that had such poor design standards, it had one peg outside the BCD, rendering the chainring effectively "indexed" in place just as these do by intent.

Same bad idea, no matter if by accident or design. Harrumph.

Best,

Dan. (...who sees bad ideas come 'round again more frequently that good ones)

[il padrone]

Strange crank designs are always fun 








(The ones I had  )






Not cranks but pretty extreme

[Andre Jute]

Holy Moses, what monsters will next crawl out of the cupboard of history? -- Aj

[NZPeterG]

Hi All

The new bolt set up from DA and more coming is to help out your not so good LBS!

WHY?

So they can work out how to fit them the right way On! Sad but true!  

Also to sale there chain rings! and not aftermarket chainrings  

It just like cars and motorcycles, there is more money in parts them the whole bike or crank etc.  

Pete
 

PS I like the bend cranks   Sold well because a longer crank is good to climb Hills! but with the bend is is shorter at the same time    Mad Idea but good to make some money  

[No]

Strange crank designs are always fun 








(The ones I had  )






Not cranks but pretty extreme

Who could actually turn the cranks on that last one?

[Danneaux]

Who could actually turn the cranks on that last one?

Possibly any well-conditioned professional cyclist. How? Well, such chainrings were rarely spun-up from rest. Instead, they were used in motorpaced records, where the cyclist was first towed up to a speed where they could actually turn such a gear, then rode even faster in the draft of a pace vehicle (shrouded automobile, motorcycle, or even a train with boards laid across the railroad-track ties to make a riding course. Here's an example: http://www.bikereader.com/contributors/woodland/murphy.html

Best,

Dan.

[NZPeterG]

Hi Dan,

 

Very Good also a few years ago they used Big Chainrings for Mountain Bike Downhill   and that was before Disc Brakes   and I do NOT mean downhill at speed on snow  

Pete

Max speed for me offroad downhill race 84kph   not any more for me I have slow down a little (to 60+kph on Sunday)

[Danneaux]

Max speed for me offroad downhill race 84kph ...not any more for me I have slow down a little (to 60+kph on Sunday)

And that is on unpaved surfaces, too!!!

Best,

Dan. (...who hopes Pete will be careful of himself and not get hurt)

[NZPeterG]

Dan. (...who hopes Pete will be careful of himself and not get hurt)

Hi Dan,
I hope not too get hurt again  just keep loose and pedal hard is all that is needed to go a little faster! But as I said i'm slowing down and having fun 

Pete........................................................................................... O' no slow down with the writing too!.......................................