Rolling Resistance

Moderators: malfukt, Steve Newton, Tacx support, JörgenJ, mcorn, Tacx Moderator, Tacx Video Production

Post Reply
Robobob
Posts: 2
Joined: Thu May 24, 2018 3:56 pm

Rolling Resistance

Post by Robobob » Thu May 24, 2018 4:14 pm

I'm a big fan of training using imported GPX files (particularly enjoy the TTS4 implementation with the Google Earth playback feature) - However, one vital element that seems to be missing is some kind of user defined control of rolling resistance for off road routes.

Unless I'm missing something, neither TTS4 nor the new Tacx desktop app seem to allow for this, which means that riding off road routes on a mountain bike feels more like riding on road with a road bike - I know it’s not possible to get the feel of riding off road 100% right, but some kind of option to add a rolling resistance coefficient to segments or all of an imported GPS track would be a great additional feature for those of us that also like to ride off road (as it is, I'm currently 3-5 mph faster riding off road routes on the trainer than in real life).

mcorn
Moderator
Posts: 7588
Joined: Fri Nov 24, 2006 8:55 pm
Location: USA, Bellingham, Washington

Re: Rolling Resistance

Post by mcorn » Thu May 24, 2018 6:49 pm

Robobob wrote:
Thu May 24, 2018 4:14 pm
I'm a big fan of training using imported GPX files (particularly enjoy the TTS4 implementation with the Google Earth playback feature) - However, one vital element that seems to be missing is some kind of user defined control of rolling resistance for off road routes.

Unless I'm missing something, neither TTS4 nor the new Tacx desktop app seem to allow for this, which means that riding off road routes on a mountain bike feels more like riding on road with a road bike - I know it’s not possible to get the feel of riding off road 100% right, but some kind of option to add a rolling resistance coefficient to segments or all of an imported GPS track would be a great additional feature for those of us that also like to ride off road (as it is, I'm currently 3-5 mph faster riding off road routes on the trainer than in real life).
Some TTS videos have additional resistance built for bumpy courses (e.g. the cobblestones on Roubaix). TDA does have road feel for the Neo brake and bike type settings.

You speed difference could be the result of inaccurate calibration. If you had a power meter, you could confirm your calibration is accurate. If you want to slow down further on uphills, you can also increase body and bike weight in the software settings. Not sure what your source is for your GPS files, but the slope information may not be accurate.

You can also make the uphill part of a TTS course more difficult in the Power Mode setting by increasing the value to above 100%.

Not sure what brake you have, but if it is the type were you adjust tension, you can make everything more difficult by fudging the calibration. After doing the normal and correct calibration, increase the tension on the brake by turning the tension knob an extra turn counterclockwise. (Do NOT recalibrate after doing this.) Don't overdo this as you can cause premature wear on everything.

Robobob
Posts: 2
Joined: Thu May 24, 2018 3:56 pm

Re: Rolling Resistance

Post by Robobob » Thu May 24, 2018 9:06 pm

Hi mcorn, thanks for the reply - Yes, sorry forgot to mention I'm using a Neo so no calibration needed as far as I'm aware - GPX files are imported from tracks I've created in dedicated mapping software/Google Earth, (don't use the ones recorded by my GPS as the elevation data can spike a lot).

As you say above, I've noticed the increased resistance in some of the videos, this is very nice - Also noticed it in the Downhill Valley VR workouts in TTS4 which are off road. This is the kind of effect I'm trying to get, feels much more like riding IRL.

Incidentally, it's not so much the speed difference that is the problem on a mountain bike but the gearing, I have both 1 by and 2x chainsets equipped MTBs, it's pretty much impossible to use the 1x on most routes as it is either too over geared at the low end (34t x 42t) or to limited at the high end - I managed to find some bigger rings and a smaller cassette for the 2x, but even then I find that the shifting patterns end up very different compared to RL.

It's a difficult one for sure, I'll have to experiment (part of the fun I guess :wink: ).

Post Reply

Return to “General Training topics”

Who is online

Users browsing this forum: No registered users and 4 guests