Upgrading from Tacx Vortex Smart to Wahoo Kickr


(Mark Goldstein) #1

After logging 20 hrs Zwift riding time on a Tacx Vortex Smart, I’m wondering what benefits there would be in upgrading to the Wahoo Kickr.

My principal reason for asking is that I struggle to generate a high w/kg on the hills with the Vortex - I either end up using a big gear at a very low RPM or a lower gear at, say, 40RPM, neither of which is sufficient to generate a w/kg typically higher than 4-5. I therefore get dropped in group rides or when trying to follow other riders, and also riding at such low RPMs is unrealistic and uncomfortable.

Has anyone made this jump? And if so, does the Kickr provide a quantifiably better “experience” than the Vortex, particularly going up-hill?


(Bertram Redmeijer (B)) #2

I got to admit that I don’t see the problem with the Vortex… It does not seem to run out of resistance (which is maximal 950 Watt), as you say you have either low RPM or very low RPM.

It seems to me that you have to use an even lower gear, so that you can keep your RPM somewhere around 80. If you are in your lowest gear and still cant keep the RPM’s up, the resistance of the Vortex might be to high - there were some Tacx’s (Tacxes?) that had a to high resistance as production error. You might want to try to borrow a power meter somewhere, or use an other brake to compare.

It might also be that your own power is just to low - no idea what your condition and weight are. But 4-5 w/kg sustained over a 20 minutes is a pretty high goal - not exactly pro level yet, but certainly above what most people do (groups on Zwift typically ride at 2.5 or 3.0 w/kg).


(Mark Goldstein) #3

My current FTP is 232, weight 70kg. The Vortex is a yellow TDF edition, bought in November 2015 and running the latest firmware.

It’s trying to hit high w/kg on, say, Richmond’s 3-minute hills at an RPM that doesn’t cripple your knees that’s the main issue.

I’ll try using my granny gear (34/27) and see what kind of RPM and w/kg I can achieve using that.


(Eric Oshlo) #4

I have both a Tacx Vortex Smart (nonTdF) purchased in Nov 2015 and a Wahoo Kickr purchased in March 2015 at different locations. I haven’t noticed that much difference in their performance in Zwift non workout mode. Thus, It sounds like there’s something else going on in your case to cause abnormally high resistance settings on the climbs.

Zwift’s settings default to setting a “smart” trainer’s resistance to simulate  ~50% of a climb’s true gradient. Have you changed that to 100%? I’ve left my settings at the default 50%, which is enough to give me a good workout.

My FTP and weight are virtually identical to yours, so I would think our data would be close. Here’s my data for 2 each Richmond and Watopia climbs on the Tacx:

Richmond  Hill 1: 0.5mi, 2:10 min, 297w avg, 95rpm avg

Richmond Hill 2: 0.6mi, 3:00 min, 237w, 88 rpm

Watopia 1st lap:  0.6mi 2:48 min 294w 96rpm

Watopia 2nd lap: 0.6 mi 2:55 min 275w 91rpm

Note that my power and cadence were both being read by Zwift from my Quarq power meter (not the trainer itself). As you can see, I have no problem keeping my cadence up while generating good (for me) power numbers in the high 3 - low 4 w/kg range - and that’s while mostly staying in the big (50) chainring.


(D W - ltb LMDGD) #5

If you want to stay in the big ring while climbing the steeper hills, I would suggest moving the difficulty slider to the left.  This can be found in the settings menu.  A lot of people call this ‘flattening the hills’ but another way to view things is that moving the slider to the left shrinks the front ring when climbing hills and makes it larger when descending.  As you become a stronger rider, you can slowly move the slider to the right or not.  The default is set at 50%.  Don’t worry.  It still takes the same amount of power to hit the same kom times regardless of where the slider is at.