Al Bundy

Hello All,

Like some who have posted on the dificulty of doing intervals on the road, I use a trainer. Am presently using HR, but would like to try power. I dont have a power meter, but I wonder if some kind soul could help me calibrate my trainer?

If there is someone with a power meter in So Cal who could waste 30 mins to an hour one day that would be great. I just want someone who can sit on the trainer and crank out some known power numbers with a speed sensor on the back wheel. I can then note power versus trainer speed. Its a cyclops liquid trainer and I think its reasonably consistent once its warm. Once I have the speed versus power data I can use that with my own bike to get at least a crude measurement and use it for intervals based upon power rather than HR. It would also be useful to test for improvement over time....

has anyone ever done this and if so is it a reasonable idea?
thanks
Mike

calamarichris

Where do you live?

IanInSD

You should get numbers similar to this...
Sp Watts
14 130
15 145
16 160
17 185
18 210
19 235
20 265
21 295
28 600
30 700

gregf83 

If you are planning on doing 20min intervals you don't really need a power meter. Just measure your threshold or 20min speed on the trainer and do your intervals at that speed or something close. If you have the Cycleops 2 fluid trainer there are others who have already done these measurements (perhaps like Ian above) and that should be close enough as well.

Al Bundy

I live in Temecula but travel often from santa Barbara to San Diego, so anywhere in this area is possible.

Iam, did you notice any big difference with tire pressure to those figures?

greg, good point - thanks not considered that. Have done the 2x8mins flat out test to get an estimate of LT, but pleasantly surprised to note that this has changed upwards in last 4 months. Have measured power on sustained climbs, but these neglect efficiency and frictional losses on the bike. As much as anything I want to get some consistent metric for intervals but also longer term tests to establilsh training progress.

thanks
mike

agarose2000

Wow - those numbers seem high. I don't have a PM, but according to that, I crank well over 300 watts per hour of riding for a continuous hour and a half which seems way too high compared to the typical 230watts I crank out on a gym bike (which also is poorly calibrated.) I'd bet tire pressure does make a difference as well.

IanInSD

The numbers I posted were from another BF member who trying to achieve something similar with his Fluid 2 to a powertap. Also, Saris does have their power curve (https://www.saris.com/comparison/trainers.pdf) available for the fluid 2 which appear very similar to numbers I posted previously. I don't have a powertap but generally my sustained power is lower overall on a trainer versus the road.

Ian in San Diego

umd

This. But also realize that the "speed" is only valid for that trainer and should not be compared to other trainers or the road.

Again it will be specific to the trainer and the rider. A much heavier rider would probably put out more power but on the road would not go as fast.