reliability info

[patc]

Hi,

Do any of you folks have any information concerning component reliability?

Lately I've had a couple of problems associated with drive components.

About a month ago my bottom bracket spindle failed during a small climb (the spindle cracked and my left crank arm was hanging off at an eccentric angle to the chain stay).

Then two weeks ago my record crank blew up (left side) and the pedal and remainder of the crank arm were left attached to my cycling shoe.

The bottom bracket was a square taper and was installed new in the single speed about a 1.75 years ago. The spindle was stainless steel.

The record crank was about 3 or 4 years old and wasn't in a crash or anything.

These issues both happened on road bikes and I swap a number of components out on a regular basis (once a year or every two years).

Is there any information on fatigue life associated with these types of components or failures?

Thank you,

[SoCalSteve]

How much do you weigh?

How tall are you?

What style of riding do you do?

Do you race?

Do you spin or mash?

Who builds your bikes?

I am sure all these questions will help us figure out what is going on.

Just askin'

Steve

[TAW]

Hmmm...all Campy stuff. ;)

[patc]

Hi Folks,

Thank you for responding.

So Cal Steve - I weigh about 215 - 220 and 6 ft 1. I don't race but I don't think I gear mash. I've worked with my fit instructor and a pilates teacher on my biomechanics. Incidentally I think this has actually made my stroke more failure prone. I now pedal through the stroke more cleanly and completely. The frames are Serotta and I have a mechanic in Palo Alto build the bikes and the wheel set. The bottom bracket is not a campy - it's a top end square taper component built here in San Jose.

I'm not sure if any one has any fatigue data on alloy crank sets but I've been informed that the square taper spindle and crank set are more robust than the current hollow tech / ultra torque technology currently available.

[e-RICHIE]

was there a bulge atmo?

[manet]

was there a bulge atmo?

http://www.nicejewishpsychic.com/

[handsomerob]

do you happen to leave your bike in the car on hot days?

[patc]

manet - I'm not sure what you mean by a bulge. There wasn't any evident mechanical issue with the crank. The break occurred at the eye (pedal spindle) - the only other strange thing was part of the fracture appeared dark while the other part appeared to be much lighter.

In terms of whether the bike had been stored in a car during hot days - no the bike wasn't ever stored in a car or on hot days.

If you folks have any other thoughts or information pls let me know.

Thanks,

[handsomerob]

manet - I'm not sure what you mean by a bulge. There wasn't any evident mechanical issue with the crank. The break occurred at the eye (pedal spindle) - the only other strange thing was part of the fracture appeared dark while the other part appeared to be much lighter.

In terms of whether the bike had been stored in a car during hot days - no the bike wasn't ever stored in a car or on hot days.

If you folks have any other thoughts or information pls let me know.

Thanks,

My response was completely tongue in cheek. ;)

[cmg]

Had terrible luck with record BB. it's normal, go to something else. chorus or centuar will last longer.

[noflysonme]

A light area indicates a new break.

A dark area indicates an old break.

The dark area is dark because air has gotten in and corroded the area.

So its been fractured for a while.

[Ginger]

Had terrible luck with record BB. it's normal, go to something else. chorus or centuar will last longer.

Knock on wood...Record BBs and no problems. (No, I haven't been running a computer for a few years, so I don't know how many miles I have on them.)

[chuckred]

While I don't ride that much compared to many on this forum (only about 4k miles/year), that includes lots of mountain biking, mountain roads, etc). In 40 some years of riding, other than in a major crash, I've broken exactly one handlebar, and it was after probably 15 years of use and had been drilled for cable routing for bar ends (was that way when I bought the bike).

Hope I haven't jinxed myself!