Max power on a magnetic turbo

People with a simple wheel on magnetic turbo, what kind of power numbers are you able to hit for what RPM?
My understanding on gearing was nothing more than push one way for harder/easier, so I’ve tried to at least look that up first to understand answers.
My bike has 50/34 on front, and lowest on rear is 12 teeth I think from trying to count last night. With the magnet on full I’m needing to hit 95 RPM to hit 330W, and ~105rpm to hit 390W.

Are there any ways to increase the resistance? The trainer seems to be screwed as tight to the wheel as I can make it.

Of not my options seem:

  1. Would a different entry level trainer be likely to offer different resistance?
  2. Spend more on a better turbo.
  3. Upgrade to a standard cassette (not essential covid work :roll_eyes:)
  4. Make do with doing up to SS/FTP rides. This wouldn’t have bothered me as not that fussed on ‘training’ and just want to be able to do some exercise and enjoy, but frustrating when the social rides I’ve tried to join have done V02 intervals, and last night was constantly being asked to go <90rpm.

PS: just to pre-empt it, yes I’m sorry wasn’t meant as a humble brag :joy:

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On the plus side, at least I now understand what is meant by a compact/semi compact /standard.

I have a 13 year old Tacx Satori, and it’s still going strong, apart from a bit of bubbling/rust on the legs. The magnetic lever indicator has slipped around, so I think max is about 7 now. With resistance on ‘6’ (which is probably more like 8/9) I am routinely pushing 260w in 50/14 (~85rpm) but I am easily able to get out of the saddle and do 360ish in 50/13.

Not exactly scientific, but I’d say you should be able to push-out well over 500w on a dumb magnetic trainer, assuming you have good tyre traction. Do you perhaps need to take the control lever apart and rebuild it, as could I, I suppose! For the record, I have always just used old road tyres as well.

Thanks. I assumed must be a problem with the trainer and should be be capable of far higher resistance settings rather than me being Chris Hoy, just wanted to check that others should do low cadence work.

Mine’s fluid rather than magnetic but a basic wheel on dumb trainer (KK Road machine) with no adjustment on the turbo itself.
I did a test when I first got it but couldn’t get into 19th or 20th gears for a long enough period to get a reliable reading. The attached is 1-8 in small ring and 3-8 in big ring.

At what cadence? I’d like the option to be 400W at normal cadences ~95. Ideally have the choice to do strength work too but seems like that is unrealistic.

If I was strong enough, 400w could definitely be achieved on my trainer. At the moment I can only manage that out of the saddle, which is pretty awkward on a static trainer!

Fluid and direct drive trainers are much quieter. I’d say if you think you’ve got a good few years ahead of you in triathlon, which I guess you have, investing in a good turbo and a fan in a good investment to make. I went through 2 crappy turbos before I got my kurt kinetic road machine and it’s dead quiet, could probably get up to 1000 watts I reckon. Never really felt the need for a smart turbo. Power numbers are enough motivation for me. Also a good turbo tyre - they are quieter and turbo optimised. I’ve shredded 2 regular tyres on the turbo. Hot rubber flying everywhere, up the walls, what a mess…

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That graph was done at around 90-95rpm at the lower power levels, dropping to around 85rpm at the higher end.

Well I insisted last year was becoming a “2 and done”, but yes seem to be carrying on.

Still completely naive to most things cycling and equipment wise. Only just got approval for turbo due to lockdown, was waiting til bought house and had a garage or somewhere to use it hence not invested already. But main reason is potentially have plans on moving country towards end of this year so want to be able to sell or take everything I own hence happy with something cheap for 6 months.

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Who’s had a puncture during a Zwift race here? I was near the end so just kept going :sweat_smile: One advantage of Direct Drive.