Gear ratio & trainer difficulty

General Discussion
1

Question please. Planning to ride Alpe d’Huez IRL at the end of this month so did Quatch Quest today with trainer difficulty set to 100%.

Felt tired for the whole of the ride and by far my worse time doing Alpe du Zwift (pb is sub 70 mins). Rode mainly in gears 4-8 as had no legs from the start of the climb, and at the end felt like I was bonking and had to drop to gear 3. Is there anyway to know what gear ratio that actually is on the Zwift hub.

My road bike lowest gear is 36 / 34T and after today confidence is not great - not too bothered about time but want to climb if comfortably IRL, so want to make sure that the lowest gear is at least gear 3 in Zwift!

Appreciate any advice.

2

Gear 3 = 0.99

(I am assuming you’re using virtual shifting on your zwift hub)

3

Hi Colin, thanks for the reply. So gear 3 on 100% trainer difficulty would be basically 36 / 36T?

4

It’s not fixed like that. Trainer Difficulty is gradient scaling - it affects the incline value sent to the trainer. On a climb higher TD makes resistance greater. On a descent higher TD makes resistance lower. It makes the hill feel steeper both up and down. On flat roads it doesn’t do anything because gradient scaling a 0% incline is still 0%.

5

Trainer difficulty is scaling the gradient, you don’t want to be changing that. Leave it at 100%.

Do you need to use virtual shifting or can you use real gears that you will be using for your IRL ride?

If it were me I’d be using real gears to see how that goes and potentially looking for easier gearing for real life.

Alpe du Zwift also isn’t totally reflective of Alpe d’Huez in real life either (I have ridden it a number of times). Try out Fulgaz and give Alpe d’Huez a go just to see what you are in for.

6

Thanks for the replies.

I’ve got a Zwift hub one so use the Zwift click for gear changes. As it has the single cassette on the back I assumed with a front chainring of 36 I could calculate the gear ratio if I used 100% TC.

I understand how T works and will continue using it at 100 for next few weeks, but wanted to understand how it would compare to my lowest gear ratio of 1.06 on my road bike for the real life climb.

I’ve got a handful of climbs on Zwift before I go so not looking to change the setup.

7

Yes, I think you’ve got this correct.

8

Be careful on that road, it’s really busy and somewhat narrow in places. Depending on which way you go up to the village.

9

It’s not just cycling up the road you have to worry about.
It’s the altitude.

You will notice that it’s harder to breathe and it is harder to push the gears.

But it’s fun.

Be careful on the decent, don’t burn out your brakes. The hairpin bends need care due to the traffic

Although it’s busy most vehicles are respectful of cyclists as there are so many.

10

And it’s a pretty fast descent down there too, even at my light weight. Maybe also because I was on a very aero bike I was going way faster than my old Giant TCR (2014 SL1) which I also rode on Alpe d’Huez.

All I can say to anyone who hasn’t done it before is don’t be a hero - just take it sensible, don’t ride the brakes too much.

11

Hi, thanks for the tips. Was planning on stopping a couple of times on the way down for photos etc. so that should cool the brakes down!