Dissapointed...

[mickle]

absolute guff, every word of it. sorry. go back to acf.

Absolute guff?? Thats a bit rich.

And please dont be rude to our guests, its not nice.

 

[dan_bo]

can't wait 'till bonj gets a fixie.

 

[bonj2]

Absolute guff?? Thats a bit rich.

And please dont be rude to our guests, its not nice.

'tis. "bends as I accelerate away from the lights", you honestly expect me to believe that??! come off it. And he was rude to me.

 

[mickle]

But it does bend when he peddles away from the lights. Mine does too. Frame flex is a widely accepted phenomenon, particularly with skinny tubed bikes. How many people have to tell you before you believe it. At some point you will have to accept that all of these nice people are telling the truth. They arent deluded, they arent lying and they arent taking the piss. When you do come to accept the truth about materials elasticity and structural dynamics in cycle frames I hope youll have the good grace to;
(1) apologise for your scandalous slanderous slurs on our collective integrity,
(2) hang your head in shame for your arrogant ignorant attitude and
(3) away and boil yer heed.

 

[spandex]

Dear Bonj

This is just a note to you to help you find out how to get your bike to flex. 1) You must be going over 3mph. 2) Turn hard into a corner. 3) Have your shopping on the back of the bike. 4) Get a bike over a £100 and not from Halfords. 5) Not ride on the pavement (as you cant get over 3mph to get round the corner). 6) Get out of the gutter when you do make it onto the road.

Thats it mate



Ar yer GET THE STABLIZERS OFF YOUR BIKE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


with love
spandex

 

[bonj2]

But it does bend when he peddles away from the lights. Mine does too. Frame flex is a widely accepted phenomenon, particularly with skinny tubed bikes. How many people have to tell you before you believe it. At some point you will have to accept that all of these nice people are telling the truth. They arent deluded, they arent lying and they arent taking the piss. When you do come to accept the truth about materials elasticity and structural dynamics in cycle frames I hope youll have the good grace to;
(1) apologise for your scandalous slanderous slurs on our collective integrity,
(2) hang your head in shame for your arrogant ignorant attitude and
(3) away and boil yer heed.

Well I once had a steel framed bike and it never bent one bit when I rode it.
I just think it may be possible that people are misinterpreting little imperfections in the road as 'bike flex' because they've read about 'bike flex' in pro racing articles and have decided that since they think they ride their bike quite fast that they think that's something they should suffer from aswell. It's not malicious lying I'm accusing people of, it's just that people subconciously see what they want to see in things.
Another minor point if I may, no-one's yet answered my question on which way it flexes, (what you would have to do to the bike to reproduce that same effect when still etc.)
If you think you do get flex, and you know you're right, then just leave it at that. Your persistence in insisting on getting me to accept it isn't doing much to convince anyone of your point.

 

[Brock]

An interesting paragraph from Sheldon Brown's article on frame materials:

Torsional/lateral stiffness

This is mainly related to the stresses generated by the forces you create from pedaling. Any frame will flex around the bottom bracket a bit in response to pedaling loads. This flex can be felt, and many riders assume that it is consuming (wasting) pedaling effort. Actually, that's not the case, because the metals used in bicycle frames are very efficient springs, and the energy gets returned at the end of the power stroke, so little or nothing is actually lost. While there is no actual loss of efficiency from a "flexy" frame, most cyclists find the sensation unpleasant, and prefer a frame that is fairly stiff in the drive-train area. This is more of a concern for larger, heavier riders, and for those who make a habit of standing up to pedal.

I experience flex in my 531 tourer, being a heavy rider of immense power, I had always assumed it was having a negative effect on my efficiency, but apparently not

 

[MrGrumpy]

can`t say I`ve noticed flex in my carbon framed race bike but I`m sure its there however the cheapy cromoly mtb i use for commuting well it bends like a banana

 

[Crackle]

Sorry I admit to not having read all of this thread.....

they bend....

"Elastic flex is like a spring, it gives back all of the energy that goes into it. There's been studies ad nauseum that proves flame-flex does nothing to affect the efficiency of a bike of it's speed. Check out Chester Kyle's "Bike Tech" series of newsletters or Ed Burke's "Cycling Science". Flex is more a control and comfort issue for the rider.

In my middle years of racing I weighed a slim 145lbs with 4% body-fat and rode the fat-tube Cannondale frames (before they came out with the slimmed down more-flexible 3.0 version). It was by far the stiffest frame ever made with less than a 1/8" lateral defection at the BB with a 200lb sideways load on the pedal (all other bikes I've ever tried had 1/2" of lateral deflection)."
Source: http://www.bikeforums.net/archive/index.php/t-138330.html

And .... you can't always tell - Scroll about a bit and read it (bottom of 368)

So! You're all right. - though I'm not sure Bonj is interested in reasoned debate?

 

[bonj2]

So! You're all right. - though I'm not sure Bonj is interested in reasoned debate?

i'm not saying it doesn't exist, I'm just saying you can't feel it that's all.

 

[Crackle]

so read the last link I put in. It justifies your view {within certain limits of the test}

 

[Brock]

I detect flex in my frame probably just by the chain rubbing the front mech when I'm honking heavily, although I'm sure I can feel it physically, I'd accept that is probably just my imagination. I know it flexes, so I feel it.
That's why I used the phrase 'experience flex', the experience being actually a slight chain rattle.

 

[mickle]

i'm not saying it doesn't exist, I'm just saying you can't feel it that's all.

You're getting there.

Can you just accept that I can make my £1000 Rocky Mountain Vertex Scandium frame visibly flex whilst sitting on it.

 

[Crackle]

I detect flex in my frame probably just by the chain rubbing the front mech when I'm honking heavily, although I'm sure I can feel it physically, I'd accept that is probably just my imagination. I know it flexes, so I feel it.
That's why I used the phrase 'experience flex', the experience being actually a slight chain rattle.

read that last link: It says somewhere that most percieved flex is in the crank and handlebars. So your front mech rub could just be your crank flexing.

In one of those links it also talks about ride harshness being dictated by frame material which is not the same as frame flex, though the two are intertwined.

 

[Brock]

read that last link: It says somewhere that most percieved flex is in the crank and handlebars. So your front mech rub could just be your crank flexing.

In one of those links it also talks about ride harshness being dictated by frame material which is not the same as frame flex, though the two are intertwined.

My cranks flexing wouldn't effect the chain line would it?