Zwift newbie

A friend who I ride with regularly at pretty much same speed is same weight and averages 285 watts.

Raw numbers don't tell the whole story, a few things here -
a) you'll get better at pedaling on zwift, it's not quite the same as outside so will take a little adaptation, give it a few weeks.
b) riding is a lot of technique, I can (and usually do) get my legs torn off in races by people with half the power output because they draft better, they pedal more efficiently, they brake on the right places and so on. This all applies to zwift too except the braking.
C) size makes a big difference on zwift especially, taller people are slower than shorter by quite a margin.

Also get a load of black crud on floor – I think it’s rubber from the belt. Is this normal?

Yep

FTP 246 watts (I think I can bump that up a bit, didn’t really understand the ramp test when I did it)

Ramp tests aren't brilliant for accuracy but they are a good place to start and give a good base line for training. I consistently get 12-13% low on a ramp test vs 20min because the ramp test doesn't suit me but it's always about the same amount out.

There's a lot of this and things you'll find odd etc covered in the Stupid zwift questions thread and it's a good place to start.

There's also a zwift club though currently it's a bit low on activity.

Black crud might be chain lube. I got similar when I tried I think a was dry lube.

Yep, black crud I get is definitely from chain lube.

Have you set your Trainer Difficulty to 100% ?
That's the first/best thing for making Zwift feel like real life. (Turning the TD down is equivalent to fitting a lower set of gears - you still need the same total energy to get to the top of the hill; you'll be spinning easier but longer.)

But then downhills are odd - if you stop pedalling, then you stop moving, but the trainer leaves you spinning against air when you're at 100% TD on a steep downhill. However, I'd rather have that (than "easier" climbs) as I'd be freewheeling in real life anyway.

I don't know if they've changed this, but I found it a real problem with the pacing robots - I'd ride with the 200w one, but lose it on the downhills as I couldn't make 200w against little/no resistance.

Also, have you calibrated your trainer?

I've been known to set the TD lower if I'm doing one of the mountain climb stages... after all, if I went and did one in real life, I'd probably fit lower gears to my real bike!

Set your trainer difficulty to zero and try riding close to 246w for 30 to 40 minutes and see if you can maintain it.

If it's easy you're probably too low, conversely if it's not possible you're likely too high. If it's just about manageable then you're in the right area.

That thread takes some reading but interesting

So - I can improve my ftp by getting stronger / lighter / lying

This means for the same watts I’ll go faster

But what would it do to the resistance applied by the trainer?

And does gearing on the bike have any impact? Atm my fastest gear is 32 / 11

Gearing could limit your cadence which would in turn impact your output/power.

Sounds obvious but it's better to have an accurate FTP than an over-inflated one.

This means for the same watts I’ll go faster

On the flat not by masses unless you take a lot off your weight/height 200w is still 200w. It will make a much bigger difference on hills where power to weight is much more important.

But what would it do to the resistance applied by the trainer?

Lower weight will mean less resistance on hills as there's less to drag up or, same as in real life.

And does gearing on the bike have any impact? Atm my fastest gear is 32 / 11

The same as in real life, if you're spinning out a bigger gear or increased difficulty will help, neither alters the power you actually produce or the speed at which you move though. (it might change how much power you can put in by virtue of not needing you to do 300rpm but if you're maxing out your power not spin speed it's not going to change much)

If that's your highest gear I'm not surprised you are spinning out! I've a compact double on mine and steep downhill can easily spin out the 50-11. My small front ring is 34t and I spend hardly any time using it. Other than the really steep roads (sustained 15%+) it only gets used for ERG mode.

This could be why you got a number from the ramp test that you cannot product freeriding. The ramp test uses ERG mode, when that is engaged you do not need to change gear. You should pick a lower gear (I use 34-22ish on a 11-25 road cassette) and let the turbo sort out the resistance.

Edit: just realised the person posting gearing details was not the OP. Have left response as is though since it could still be valid.

edit - just read the post properly 😉

you'll easily be spinning out in that gear. What is your trainer? Some have very poor accuracy, but the numbers don't look entirely unreasonable unless you think you are really fit! Your (estimated) FTP will likely increase a fair bit when you get used to riding. I was around 250W when I started during lockdown, a year or two later I did a best of 360W for 20 mins.

Charliemort and gasper are the same person. Stw seems to have renamed me!

Someone has developed an App that sets "virtual gearing" in Zwift so that MTB gearing works better. I've seen it mentioned in the Zwift forum. I'll see if I can find a link.

Looking at the account created dates (2009) looks like you may actually have two accounts. Perhaps somehow two got created against one email. All the post history is against charliemort. I would suggest logging out and then logging back in using the user name instead of email. I had something like this year's ago of Facebook with two accounts in the same email. They had different passwords so depending on which password I entered I got shown a different account.

So in the gearing thing……. Does it assume you are in a certain gear? Does it assume you have road bike gearing if doing a road course?

I’m using my gravel bike (really an mtb) cos road bike has 1 x 13 so won’t fit; I usually run 32 - 10/42 or 36 - 10/42 but on trainer have 11-28 cassette

So in the gearing thing……. Does it assume you are in a certain gear? Does it assume you have road bike gearing if doing a road course?

The "gearing" thing isn't really gearing, it's how accurately it simulates inclines, so at 50% (default) difficultly a 10% hill actually provides the same resistance as a 5% hill (not quite but it illustrates the point).

It doesn't assume you have any particular gearing. But as it's mainly simulating road it's logical that road gearing will work best. Using the gears your gravel bike has you'd not expect to have a high top speed outside and similarly don't inside.

Here you go..

FORUMS.ZWIFT.COM "https://forums.zwift.com/t/new-to-zwift-hub-trouble-with-mtb-setup-and-resistance/595553"

New to Zwift (Hub), trouble with MTB setup and resistance - Zwift Equipment - Zwift Forums

Hi Zwifters!
I am relatively new to Zwift, I only got two rides in my legs as of today.
I bought a Zwift Hub and am running Zwift on an AppleTV. Since don’t own / never owned a road bike I am using my 29" Mountainbike …

The App is called QZ and the developer has chimed in on the Zwift forum.

Okay I’ll do my nut in with this if I’m not careful

It must assume some sort of gearing to set the resistance. If I’m say in 8th gear at 80 cadence on the flat and it says I’m at 250 watts it must have made an assumption on gearing?!? I think…0

It must assume some sort of gearing to set the resistance. If I’m say in 8th gear at 80 cadence on the flat and it says I’m at 250 watts it must have made an assumption on gearing?!? I think…0

TAke away the idea of 'setting resistance' unless you are in ERG mode.

Basically, there's 2 ways to 'do' Zwift:
1 - ERG mode - this is for workouts. It will 'make' you create whatever power you've set it to, regardless of the cadence. If you set it to 250 watts for 30 seconds (as part of a workout), the trainer will offer resistance that equals 250 watts... whether it's 50RPM or 100RPM, for 30 seconds. Better trainers are better at this.

2 - Free ride/race - this is just like normal cycling. When the road points up, it's harder to pedal. Regardless of gearing, it'll be the same incline (box hill is box hill, whether i'm on a 46/17 fixie, or a compact road bike).. of course it'll be 'spinnier' on a lower geared bike.

Trainer difficulty simply adjusts the 'road inclince realism'.... it doesn't make climbing it any easier per se - it'll still take the same amount of power to climb the hill in zwift, but it might work better with some gearing set ups..
So if a road is 10% incline, you can make it FEEL like a 10% incline (trainer at 100%), or FEEL like a 5% incline (with trainer at 50%)... but it'll still 'treat you' like it's a 10% incline when it comes to power needed to climb.

Think of a hill local to you. It's the same hill regardless if your front chainring is 36 OR 56.... it's just it FEELS easier in the 36 front chainring...

DrP

"If I’m say in 8th gear at 80 cadence on the flat and it says I’m at 250 watts it must have made an assumption on gearing?!? I think…0"

Not really. All it cares about is the torque and rpm at the cassette. It doesn't care whether you're spinning a little gear at 300rpm or a giant one at 40rpm. just as outside, the actual road speed could be the same.

I find these things can make your head spin when just thinking and talking about them, but when actually riding it all seems intuitive and obvious.

However, it really doesn't help that they talk of "trainer difficulty" - i'm sure they could have come up with a better term. On full difficulty it just means you have to use a wider range of gears and change more often as inclines have more effect on resistance. It doesn't affect your speed or the ease with which you produce that speed or watts. It's not like difficulty level on a normal video game - it's just a matter of personal preference.

I’m probably deluding myself but outputs don’t seem to reflect what I’m feeling?

Well, unless your trainer isn't properly calculated, your numbers are almost certainly a reasonably accurate reflection of your power output. You may get different outcomes from a ramp test v an adjusted 20-minute effort depending on how your physiology works, but your figures don't sound wildly improbable.

I'd try not to fret too much about power outputs and just use Zwift for a bit. If you're going to use workouts on the platform, you have a starting point, but you can always re-test / adjust at any point if your efforts feel too hard / easy. Bear in mind too that there's more to fitness than just having a high ftp. Two people with the same ftp can have quite different performance if, for example, one of them recovers better from repeated high intensity efforts or can maintain a high percentage of that ftp for longer if that makes sense.

But basically, I wouldn't worry about it.

Yes it will be designed for road bike gearing (when not in erg mode). You will probably find it too easy to spin out with a 30T chainring. I spend all my time in the big ring (50ish).