Swapped trainer tires on Wahoo Kickr Snap now resistance is too high?

General Discussion
1

Hello!

First time posting here and after doing a lot of digging I haven’t noticed a topic like this so far. I have worn out my previous tire and it was time for me to replace it. My current FTP is 303 and after swapping tires I hopped on a workout. During the warm up I drove myself in exhaustion to the point that I couldn’t finish the workout. Then I tried a slightly easier workout, still could not hit my numbers…Then I tried a free ride and it still felt like it took a lot of effort to pedal. I’m on my 30th week of daily zwifting for an hour since I’m a new parent and this is how I aid my mental health so this has been really frustrating.

The next day, same issues. I did an FTP test and I could barely hit 320w per minute and was given a score of 240. This is all fine, I can work with those numbers I suppose but I just want the resistance to be what it used to feel like before I changed tires (previous tire was a Continental Hometrainer - new tire is a clincher / non trainer regular tire). I adjusted the knob as the setup guide is asked to perform, I calibrated the trainer and performed the spin down and still the same…I hopped on my wahoo app to calibrate the spin down between 10-15 seconds and still get the same results.

Now I never experienced something like this and I’m wondering if I’m missing something here. Has anyone else experienced something like this before? Is there a thread already going that anyone can point me towards to? I already ordered a new Conti Hometrainer that arrives next week and I’m wondering if that will fix the issue?
For the most parts I’m content with Zwift (except when the game crashes and I’m told that it is MY CONNECTION that is the issue - I’ve learned to just suck it up and deal with it and the frustration)

Anywho, looking forward to hearing from y’all. And please spare me from acronyms, a lot of them I do not recognise!

Sincerely,
Frustrated new zwifter dad

2

You might want to contact Wahoo support.
Quick question, prior to the spin down, have you warmed up by riding for about 10 mins or so?

When I had a Snap, I would, prior to any ride, inflate the tire to exact same pressure, turn the knob to tighten the exact same number of rotations, do a 10 min warmup ride at the same pace then and only then would I do a spin down calibration using the wahoo app only.

Here’s a link to support at wahoo

2 Likes
3

Hi @Alan_Barbaran_PDX_OR

Is there any waxy buildup on the roller that contacts the tire? If yes - scrape that off without scratching up the roller. If the protective wax on a brand new tire transferred to the roller - it increases the diameter of that roller which throws off your distance / power./ speed the trainer thinks you’re doing.

Also - if your old tire was super-worn out (like you can see the tire casing), that changes the effective diameter of the tire enough in the other direction.

Those two things added together might be the reason why you’re feeling what you’re feeling.

4

I think there is a big difference in the rolling resistance between a hard smooth trainer tire, and a regular road tire. At least that’s how I remember it from when I got started using a wheel-on trainer.

I abandoned that setup as soon as I could afford to, because with “calibration” of a wheel-on trainer that uses a knob to set the tension, with the unknown variable of tire pressure, I was never able to get repeatable results.