IDT effect on Frame and Wheels

[Wheelsuck]

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Heard that your Alu Frame and back wheel are weakened when using them on an IDT. Makes sense that there is limited flex on the frame/wheel and it plcase extra stress and is probably true but to what extent anyone have any technical info, anecdotes etc to help me understand the effect on the frame

[SwissVan]

 

Have used IDT for many years (about 8 years) and never had a problem with Alu frame, most of it was on the same frame (exocet).

Trainer was a Cateye 1000.

 

As long as you dont overtighten the wheel / fork clamps and dont try bunny hopping your frame will be ok.

 

 

[Red Zone]

As long as you dont try cranking out big out of the saddle sprints I dont think you put any more stress on the bike than normal riding, remember that the frame doesnt take any of the normal knocks from our well maintained roads.

[Slipstream Sean]

What about a carbon frame, is it safe to use IDTs with a carbon frame or will they eventually cause the frame to weaken and crack?

[Wayde Kennedy]

I have used between 10 and 20 Cateye CS1000 trainers for the last 10 years in a group-training environment, with prbably 1000 classes in that period, and have never seen a frame damaged..

 

Tyres do wear slightly faster, but not amazingly so. There are slo specific IDT tyres now available...

 

If anyone has a CS1000 to sell, I'm always interested.

[GoLefty!!]

interesting question....

 

I guess it would depend on the weight of therider and the vigor of their exercise which will bend (deflection) the tubes continuously.

 

Most frames ar fatigue tested in this manner and the better frames achieve an equivalent life of over 10yrs so I think most frames are pretty safe.

 

Weight limited frames I'd keep very far from an IDT though

[Li Mu Bai]

Friend of mine broke his carbon frame  - best guess as to how, was flex stresses from the IDT.

you shouldn't have any issues with an alu frame.

 

[Wheelsuck]

Yeah know to stay away from the IDT with a carbon bike it is just that my favourite alu frame will now become the Indoor Bike and would hate to see her hurt. Found ealier on that the rear tyre does wear quite quick and now have the Conti Indoor tyre, which is a bitch to put on and ugly as sin but lasts much longer. 

[SwissVan]

Friend of mine broke his carbon frame  - best guess as to how' date=' was flex stresses from the IDT.
you shouldn't have any issues with an alu frame.
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You saying or guessing that carbon frames are more susceptible to flex and flex related stress?<?: prefix = o ns = "urn:schemas-microsoft-com:office:office" />

 

Interestingly my alu frame that I used for so long on a IDT had a 100% carbon fork, and it?s still forking just fine.

I do believe that most concerns regarding IDT and frames is mostly just urban legend type fear.

 

 

 

 

[The_Break]

Reason I only ride aluminium on indoor trainers is that aluminium has a uniform (in all directions) strength/stiffness whilst carbon fibre is normally designed to have strength/stiffness in certain direction depending on the lay-up. For me that means if it goes wrong on the trainer you may end up damaging the carbon.

 

With an alu bike I am not too concerned about this. However, aluminium is not very good when it comes to fatigue stress, that means if you ride on an indoor trainer do not flex the bike from side to side as you would when climbing a steep hill. Rather keep it fluid and ride seated at high power.

 

Personally I use a set of rollers with resistance and can do sessions at 400W comfortably. I have even taken then over 500W seated to see what happens. It is around 500W that things start to get a bit rocky as you are moving at about 60-70km relative to the rollers and that is an awefully narrow "band of road" you are try to stay on.

[Fitter]

Urban legend! Frames flex less on an IDT than they do on the road. The biggest danger is from sweat damage.

[Minion]

 

 

Frames flex less on an IDT than they do on the road.

Do they, though? That also wouldn't necessarily mean that the stresses are less, since it could be flexing in different places.

 

My gut feeling, though, is  that, unless you're pretending to lean into a corner like Valentino Rossi while clamped into the IDT, the stresses in the rear triangle will not greatly exceed those experienced on the road and will almost certainly be less than when you hit a pothole or the like.

Edman2010-02-12 11:42:57

[Sequoia]

Due to working in IT, I see precious little daylight and spend an inordinate amount of time on my IDT. I have an old steel frame that is permanently mounted on the IDT. There is a LOT of flex when I'm going for it. But (big BUT) this frame has always been very flexible and I'm a big 105KG lad. It flexed out on the road as well.

 

I think you are more aware of the frame flexing on the IDT than out on the road? It is a bit disconcerting to see a front wheel rolling because of fork flex.

 

 

 

Maybe it is just us big guys worrying about things like that...

 

 

 

I would really like to see someone doing a proper analysis of the situation. There are a couple of factors to take into account, but in the end, all relevant stresses from the interaction between bike/cyclist and the road must feed through the axles into the frame. In the case of the IDT, the axle is connecting the bike to the IDT. It won't be as simple, but is something to think about.

 

Sequoia2010-02-12 09:49:30

[GoLefty!!]

 

Urban legend! Frames flex less on an IDT than they do on the road. The biggest danger is from sweat damage.

 

complete and utter Bullsh*t

 

[Christie]

My 09 Cannondale owner's manual states that care should be taken to protect the frame from sweat when used on the indoor trainer.

In the northern hemisphere, lots of people ride idt's over the winter - since this is where most of the worlds high-end bike market is, I'm sure if it was a problem, there would have been big warning labels on the frame, on the idt and in the manual.

 

[GoLefty!!]

cannondale make that statement because of concerns with the paint they use.

I know of many cannondale frames that have suffered paint damage due to sweat, but not frame damage.