Tuesday, February 13, 2007


I was just riding along...

No really, I was. I was trying to sprint across Clark Dr. in a gap against the flashing green light. Apparently the tensile strength of my chain is greater than the torque strength of a 5 year old tubular chromoly BMX crank.

Component failures like this are terrible, because they happen only when you are exerting maximum force on your machine. Its very hard for the human body to react quickly when conditions (such as having a crank under your foot) suddenly change.
I reacted only after my groin area had hit the seat post and I was still being dragged into the intersection by the momentum of my 42 lb bike.

I will continue to react by upgrading the cranks to some free ones from Ride On, and putting a bigger chainring on the bike. Obviously a bigger chainring will not help me put any LESS torque on the cranks, but it WILL help me find the next weak link in my drivetrain.


nb said...

Oh snap indeed! Everyone loves the Masher!!

marlo said...

Do you have any idea how happy I am that you titled this "OH SNAP!"?

It's a rhetorical question, but: Really, really happy. :D

Nick said...

Won't the larger chainring reduce the torque on your cranks in a reversal of micro-gearing tendencies?

midnightsimon said...

Shit man, good thing this happened now, and not 3 days from now. Fucking good thing it didn't happen on the Hellway.

((lyledriver)) said...

To field your question.. The differences in torque acting upon two different chainrings for a given gear ratio is proportional to each chainrings radius. As I am increasing the gear ratio [along with the chainring radius], I will be not only putting more tension on the chain, but more torque on the chainring. That being said, the amount of torque my legs can produce and apply to the cranks will not change.

Therefore, my bike is now FUCKING FAST, as opposed to just FAST.

redskiedmorning said...

it's a good thing the mechanical failure occured in sweet Canadia... allowing the machine to be made even more marvelous in time for MBW. I hope you're studying your maps well :)

the hopes of a nation rest on your shoulders, Lyle!

Nick said...

I was thinking of this, but it's more geared (heh) towards chain tension: http://www.gsportbmx.co.uk/support/rideuktech/super_small_gears.html

You're absolutely right given that torque = (distance to center) x force.

Are your free crankarms the same length as your broken ones?