Re: [CR]Frame Flex Testing

(Example: Bike Shops:R.E.W. Reynolds)

From: <>
Subject: Re: [CR]Frame Flex Testing
Date: Wed, 28 Sep 2005 22:40:33 +0000

Without getting into the testing methodology, the conclusions on the web site cited below are in my opinion useless.

The author claims there is no downside to a frame that is too stiff. That in my opinion is just plain wrong. Again, a Raleigh 3sp is super stiff, but dead. A frame must be neither too stiff or too flexible. It must have flex characteristics that enhance the riders pedal stroke without causing a sub-optimal amount of additional body motion.

Without getting drawn back into discussion that is in the archives - remember that frames DO NOT absorb significant amounts of energy - they are big springs.

The author of the frame flex tests and discussion cited below seems to have missed this important point.

Mike Kone in Boulder CO

-------------- Original message --------------

> You might want to start at Sheldon's archive of Damon Rinard's bike

\r?\n> tech site.


\r?\n> Almost all the tests include frames from the pre-'83 time period or at

\r?\n> least a "KOF" frame of some kind.

\r?\n> best,

\r?\n> Brandon"monkeyman"Ives

\r?\n> Vancouver, B.C.



\r?\n> On Wednesday, Sep 28, 2005, at 13:20 US/Pacific, charles nighbor wrote:


\r?\n> > IN RIDE Issue Number 29 WINTER 2005 Page 139 there is a very

\r?\n> > interesting article on Frame Flex Testing with a Jig. Than on the

\r?\n> > following pages five frames are tested (Yes Modern new frames way past

\r?\n> > 1983 cut off but still tests results worth noting) and worth studying.

\r?\n> > When we discussed brazing materials silver versus brass and testing of

\r?\n> > them it brought this article to my mind. If you get a copy decide which

\r?\n> > one you prefer over the others. Than decide how it would affect ride.

\r?\n> > Then read how it did ride. See if you can go from test numbers to a

\r?\n> > correct interruption of results. I wonder just how much testing was

\r?\n> > ever

\r?\n> > done on steel lugged frames we all love and admire?

\r?\n> > Charles Nighbor

\r?\n> > Walnut Creek, CA