Traîner feels easier after wheel change

Hi all,

For the last 2 months I used my outdoor wheel\tyre on my Tacx flow Smart. I finally bought a second wheel and a training tyre. On my bike my cassette was a 11-34, couldn’t found the same but the vendor told me I would not feel the difference with a 12-32.

So I use my trainer with a 700x25c tyre and a 12-32 cassette. (Outdoor tyre was 700x28c).

I calibrated the wheel with the Tacx app before launching Zwift. Then I noticed that everything felt way easier.

With my outdoor wheel / cassette, it was really difficult to go up and maintain 200+ Watts and now it’s easier. Pedal stroke feel more smooth, etc…

I checked everything (tyre pressure, etc…) but everything look Ok. Also I noticed it feels a little bit easier to push on the “plastic button” to make contact between my rear wheel and the trainer.

Is there something wrong with my set up or is it normal that it feel easier\smoother with a new wheel, tyre and cassette?



It shouldn’t be feeling easier with those changes, it should be feeling the same if the old and new setups were/are both correct.

By that, I’m referring to the setup of the trainer, the tyre pressure, tension of the roller against the tyre and the calibration. Having that different cassette should make no difference whatsoever apart from giving you a slightly less easy bottom gear for hills and a slightly slower top gear for the flats.

What jumps out is the difference you said you feel when securing the roller against the tyre. Hopefully someone who has a Tacx Flow can jump in and comment on how this should work.

thanks a lot fo your reply.

on the Decathlon website they say the wheel is for 11 speeds (my bike has only 8). The cassette is an eight speed but there’s a kind of spacer for 10-11 speeds. Should i use it? Before i put my new wheel on the bike, the casette was slightly moving from left to right but after i put the wheel on the bike it’s not moving anymore.

I just call the team at Decathlon and the person i talked with said it’s normal it feels easier because before i was using my road tyre on the home trainer. The training tyre “slide” more on the resistance so it’s slightly easier to spin the wheel.

Don’t know if it make sense…

That kind of makes sense. The road tyre will be made of a stickier, grippier rubber. The training tyre will be a tougher, harder rubber to resist the damage rollers eventually inflict on normal road tyres.

It shouldn’t make any difference to how it feels to pedal when you compare a road tyre to a trainer tyre, if both are set up correctly. At least one of those setups is/was wrong and inaccurate. It’s impossible to tell which, except that you can try and check now that the new setup is correct in all ways as recommended by the trainer manufacturer.

The only difference that a trainer tyre vs road tyre will make is noise and longevity/wear. And possibly no difference in those either.

Well, I just did another workout and it works great.
Maybe my previous setup was wrong but I clearly feel that everything is smoother and slightly easier.

Maybe the new cassette helped?

You’ve not made a dramatic change with the cassette and the ratios away from the extremities will be almost identical.

It’s more likely that your issues lied with the tyre/pressure.

Anyway now it’s working shouldn’t you be riding.

Ride On!

I did the exact same thing when I was using the wheel on trainer. When I had my old GP 5000 tire on the trainer, my FTP was in the 240 range - power output seemed to match the Strava estimates for outdoor rides as well. When I switched out for my Elite Trainer Tire, the workouts were much harder and my FTP actually dropped ~20 points. I then switched back to GP 5000 and the riding was all of a sudden very easy again.

Fast forward to now, I just got the Kickr v5 and my FTP is in the 240-250 range, so I think (at least in my case) the trainer tire was adding much more resistance than expected.

tyre changes can effect feel as some are ‘grippier’ than others

But that implies that either the earlier or later setup was inaccurate - e.g. the earlier being inaccurate with a slipping tyre.

The previous tyre was my normal road tyre so it was probably more stickier than the training tyre I use now.

Anyway I’d check the pressure again, just to make sure it’s ok.