FRAME STIFFNESS

[greyingbeard]

how heavy are you fatboy ?
that same bike with a skinnyribs on it might not flex at all ?

I've experienced a cheap rack wobbling, very offputting, rack was ok when new but must have weakened over time. replaced it with a tubus £££ and havent toured laden since ! Ah well.....
Im also a lot fatter than I was....
Could this be a coincidence


anyone for a doughnut ?

[Samuel D]

This video of chainstay flex in a carbon-fibre road bike, though amazing to me, has only been viewed a couple of thousand times. So I’m posting it again. I wonder how an average steel frame flexes in comparison? Even more?

(Carbon-fibre bicycles so often sound a bit like the one in that video. The other day I saw a man on a genuine Alex Singer. It was deathly silent, like a Rolls-Royce cruising past! I was tempted to chase him and ask how he made the drivetrain so quiet.)

[fatboy]

how heavy are you fatboy ?
that same bike with a skinnyribs on it might not flex at all ?

I've experienced a cheap rack wobbling, very offputting, rack was ok when new but must have weakened over time. replaced it with a tubus £££ and havent toured laden since ! Ah well.....
Im also a lot fatter than I was....
Could this be a coincidence


anyone for a doughnut ?

I am fairly heavy but the rack is a Tubus and new. It's definitely about organising the weight right I reckon

[mig]

in comparing frames for lateral stiffness how much part is played by the chainset?

the most noodly feeling frame i have is tange cromoly 4130? with a stronglight escape chainset. the stiffest a 631 frame with a dura ace track chainset. am i actually bending the crank as much as the frame?

[Keezx]

A part of what you see and feel is always the crank flexing....how much , wel that's not so easy, you will need to examine that separately.