Race vs "normal" mtb frame

[Witkop]

ok... A carbon SS is a recipe for disaster....

 

The tension put through the chain stays and the BB is far more than a geared bike. This causes stress, which in time causes the fibres to rub, which causes failure and potential death... (dramatic but you get what I mean)

 

Also, the severe lack of lateral flex makes the bike very twitchy on those big effort climbs where you are out of your saddle fighting the bike just to turn the pedals.. (see above strees point)

 

Steel gives you whip and a bounce and doesnt fight you.... Comfort and ease are paramount in a SS especially if you want to use it often and/or race/spend long days riding on it.

 

I have tried all matter of material for my SS frames and go back to steel every time.

 

PM me your budget and or specs and I can help you out. I have a store full of SS gems.

 

I even have some ecccentric axel real hubs so you can run a regular dropout bike SS without a tensioner.

 

I disagree with Singspeedguy. Carbon SS bikes pose no risk at all to their riders. Simply because if you use carbon on a single speed you are a poser (and possibly also drive a BMW and live in the Northern Suburbs of Joburg) and do not have the leg strength to break the frame.

 

So you will be safe on your carbon bit. Just don't let a real ss rider touch it. ever.

Edited November 9, 2013 by Witkop

[Bad Girl]

Ok.. So an 'engineer' would be rolling around? Really? And what do you think I do oh pearl of wisdom?

 

Look, epoxy and weave in carbon can be manipulated and woven to distribute flex in certain ways and accept some lag. The problem is most carbon geared frames arent designed for the severe amount of CONSTANT lateral flex.

 

On a geared bike you are out of the saddle seldom and you flip between your ratios for an even distribution of power/effort. On a SS you are out the saddle pulling the handlebars just to get you pedal stroke through 360. Wide or wriggly bars on a SS are commonplace as this allows more pull through the arms at less effort on those punchy climbs where you cadence slows down to nothing.

 

NINER make the AIR, cool. I had one and I broke it. Not from a crash or from an accident. The chainstay cracked in a puff of disaster on a big ass hill. Not all will do this I am sure as most people probably dont ride their SS in every race, over the Alps, across South Africa etc.... But a Mountain bike cant be wrapped in cardboard surely, even if it is 'my preciousssssss' carbon.

 

So like I said, enjoy what you will, ride what you want to. But when the BB starts emitting a sound similar to kindling at the birth of a new fire or your chainstay decides to crack, dont say you havent been warned.

 

Eldron, carbon is definitely frame specific as it will be influenced by how the weave was patterned before the epoxy was pulled through. But like most of you should know, carbon frames/forks have a limited time/km warranty which is due to the material and the stress being put through the frame. Couple this with the rigours of pulling/fighting the bike up hills constantly and it accellerated the process.

 

So basically due to the nature of the materials, Hooks' Law sits at a far lower level with carbon than steel and flex is essential to stop fatigue and the stays becoming brittle over time.

 

If you can see what im talking about, cool. If you cant then the answer is orange, I will forever be wrong in your eyes and wont justify this any further.

 

Yes, we are all entitled to our opinions but rule of thumb (funny if anyone remember the opening scene to Boondock Saints) says that experience is often the best teacher and if you look at most SS merchants, they ride steel. It is not coincidence, we could argue this for 600 years but just go ride, go explore, go and try out your carbon track frame etc and after 6 or 7 years come back to this topic.

 

Yes, like the brake threads and the riding style threads we can all log on and belittle or argue with people but just be aware that their OPINION and their input is often the culmination of years of experimentation and trial.

 

Engineers rolling around laughing? I scorn you without really taking offence.............

 

Like I said, an F1 carbon engineer (or any properly qualified carbon engineer for that matter) would still be rolling around the aisles. Yes, you are entitled to your opinion but it is an opinion and your opinion is dangerously misleading and misinforming. Like they say, a little knowledge is more dangerous than none at all.

 

Here are some pictures of F1 carbon gearboxes and the winning Audi from Lemans. These are structural members of the chassis and handle 800 plus horsepower plus all the suspension and brake loadings.

 

By contrast a human being average 0.25 to 0.30 horse power with short burst for trained high level athletes reaching 600 plus watts or 0.80 horsepower. Some sprinters get close to ONE horse power (746 watts)

 

Please preface your opinions by saying something like “I believe” or “In my opinion” so punters know it is your opinion not irrefutable fact.

 

Oh, and before you bamboozle people with things like Hooks Law, take a look at what Hooks Law is all about on Wikipedia here: http://en.wikipedia....Hooke's_law

And right at the top of the article: “Hookes's law is only a first order linear approximation to the real response of springs and other elastic bodies to applied forces…

 

 

 

 

 

HTC rider, power output? dont know but he still rides carbon:

 

 

Chris Hoy, bench pressing 631kgs, rode carbon bikes:

 

 

Edited November 21, 2013 by Bad Girl