Advertised incline simulations

Gasperoni

Apologies if this is a daft question, but does the amount of resistance / percentage incline simulation provided by a smart trainer change with respect to weight?

I would like to be able to replicate climbs on a smart trainer but at 105Kg I have this idea that if it can provide a 15% simulation for an 'average' sized rider (or at least more average) then it stands to reason that the same simulation would require more power for a heavier rider? Then I think 'but the wattage required for me to get up a 15% incline in real life would 'only' be 4-500 watts (thats a wild guess btw) and these things are rated for well over 1k watts?

I tried asking a manufacturer but they basically said 'you should consider product x or product y'

Ideally I would like the climb on the trainer to feel pretty close to the real thing. The point being that I can practice climbs until I can do them within my limits with relative ease, then I have a good indicator of how I will be on the real climb. Obviously, if there is a significant difference between a smart trainer and the real thing then it might not be as much use to me. I appreciate it won't be quite the same as regards getting out of the saddle but I am happy to stay in the saddle for these purposes.

Hope someone can help clarify for me. Can I realistically simulate a 15% climb at 105Kg?

napoleond

On a program like CycleOps VT etc with a smart trainer, it takes into account your weight, so the resistance increases according to the percentage and the speed you move at on screen is based on your watts per kg.
So you'd move slower for any given wattage power output.
I have a wahoo kickr 2 and it works really well.

Gasperoni

Thanks for that. Are you saying it compensates for resistance by making you do less watts, but for longer (and ultimately having to produce the right amount of power but at a different rate)? Does that then mean a ride at 15% on a trainer won't require the same power at the same rate as a real 15% climb for someone who is 105Kg? It is still not completely clear to me. Can I realistically simulate a 15% climb at 105Kg?

napoleond

Gasperoni wrote:

Thanks for that. Are you saying it compensates for resistance by making you do less watts, but for longer (and ultimately having to produce the right amount of power but at a different rate)? Does that then mean a ride at 15% on a trainer won't require the same power at the same rate as a real 15% climb for someone who is 105Kg? It is still not completely clear to me. Can I realistically simulate a 15% climb at 105Kg?

You are massively over thinking it.

Your speed on a climb is dictated by the amount of watts per kg.

I weigh 85kg at the moment (christmas weight). Say I ride at 300w up a hill on Zwift.
You would have to do around 370w to go the same speed as me up the hill. Or if you rode at 300w, you'd be moving slower than me.
The algorithm is set to be closely related to real life. In my experience, especially using Cycleops Virtual Training is that it is really quite accurate in terms of climbing speed.

In short - It's not the resistance that is the factor, it's how hard you are pedalling/wattage output that governs the speed on screen. Yes it's nice to have accurate resistance but you still have to put the watts in whatever the resistance is.

The harder you pedal the faster you go.
The heavier you are the harder you have to pedal to hit a certain speed.

markhewitt1978

Gasperoni wrote:

Apologies if this is a daft question, but does the amount of resistance / percentage incline simulation provided by a smart trainer change with respect to weight?

I would like to be able to replicate climbs on a smart trainer but at 105Kg I have this idea that if it can provide a 15% simulation for an 'average' sized rider (or at least more average) then it stands to reason that the same simulation would require more power for a heavier rider? Then I think 'but the wattage required for me to get up a 15% incline in real life would 'only' be 4-500 watts (thats a wild guess btw) and these things are rated for well over 1k watts?

I tried asking a manufacturer but they basically said 'you should consider product x or product y'

Ideally I would like the climb on the trainer to feel pretty close to the real thing. The point being that I can practice climbs until I can do them within my limits with relative ease, then I have a good indicator of how I will be on the real climb. Obviously, if there is a significant difference between a smart trainer and the real thing then it might not be as much use to me. I appreciate it won't be quite the same as regards getting out of the saddle but I am happy to stay in the saddle for these purposes.

Hope someone can help clarify for me. Can I realistically simulate a 15% climb at 105Kg?

Any decent simulation will ask you for your weight before you start the program. Zwift and Tacx Training Software do this, I would imagine most others are the same. Most will also have a trainer effect setting where you can dial down the resistance even though the power output requirement for a certain speed remains the same.

OfficerDigby

The answer is.

If the machine can simulate the watts for say a 75kg climbing a 15% hill at nominal low speed (flywheel/tyre speed)

Then for a 105kg rider the trainer will not reach the required watts to simulate them climbing 15% gradient at the same low speed (flywheel/tyre)

Typically the rider would have to ride faster (flywheel/tyre speed) to reach the watts.

Then the software would do a calculation and reduce the virtual rider speed (speed in game/program) to what it would have been given rider weight.

In effect you'd be cycling up longer less steep climb....

You could increase you gearing to slow the cadence down again, and it would them be debatable if there is any difference. Presumably the difference in interia in the turbo would result in slightly different feeling.

The reason why people probably don't really care is if you can do the watts/kg you can do the watts/kg!