Smart Trainer Power Meter or On Bike Power Meters: Which are you using on Zwift?

[gSporco]

Hopefully, this isn’t a stupid question.. but here it goes?

So I have a Quarq Power Meter on my Bike which also provides Cadence info, and both functions are accurate for my needs.
I also have a Kinetic Road Machine Smart Trainer with their version of Power and ERG mode.

I like the Kinetic, but its fault lie in tire slips when sprinting and the ERG mode or Gradient adjustments aren’t smooth.

So my question:

I want to upgrade to a Kickr, Kickr Core or Saris h3.. Based on their reviews they all have their pros and cons.. Mainly, Power Meter Accuracy, smooth ERG transitions or Cadence issues.

If I already have a Power Meter on my bike with cadence.. Should I just use that with Zwift no matter what trainer I buy, and just use the trainer as the control only?
Are you using the Power meter on your bike or on the Trainer? Whats the Pro an Cons of this?

Basically, I want the Saris H3.. reviews state that its the smoothest and best feeling trainer with near immediate transitions.. However, the cadence is laggy and as always the PM will be different from the bike.. So am I stupid in thinking I can just use my on the bike PM and solve the Saris Cadence and PM inaccuracies this way?

Thanks!

[cdncyclist]

I use the PM on my bike for power info for the trainer for consistency. You state you are happy with your PM and it meets your needs, so would make sense to stick with it.

[gSporco]

I use the PM on my bike for power info for the trainer for consistency. You state you are happy with your PM and it meets your needs, so would make sense to stick with it.

So you have a smart Trainer with a power meter like a Kickr or Tacx, and still use the PM on your bike when on Zwift? If so, why did you decide to do it? For consistency when riding outdoors and indoors? Or do you feel your Trainer PM isnt as accurate?

thank you

[TheRich]

So you have a smart Trainer with a power meter like a Kickr or Tacx, and still use the PM on your bike when on Zwift? If so, why did you decide to do it? For consistency when riding outdoors and indoors? Or do you feel your Trainer PM isnt as accurate?

thank you

The data from a PM could go to a head unit to something like GC or WKO while trainer data goes to Zwift and Strava. But if you're not doing that, it's easier to just disregard PM data.

My last ride had a 1.5% power difference and a 1 rpm difference in cadence between an H3 and Vector pedals. Well within an acceptable margin of error.

[LanceLegstrong]

I use my PM pedals for all the data (cadence, power) so I get the same data for outside rides. My smart trainer just broke and I'm looking at the same trainers you are. Trying to gauge whether the Kickr is worth $300 more over the Core. Anybody compare the two?

[gSporco]

So you have a smart Trainer with a power meter like a Kickr or Tacx, and still use the PM on your bike when on Zwift? If so, why did you decide to do it? For consistency when riding outdoors and indoors? Or do you feel your Trainer PM isnt as accurate?

thank you

The data from a PM could go to a head unit to something like GC or WKO while trainer data goes to Zwift and Strava. But if you're not doing that, it's easier to just disregard PM data.

My last ride had a 1.5% power difference and a 1 rpm difference in cadence between an H3 and Vector pedals. Well within an acceptable margin of error.

TheRich, The Saris H3 seems like the perfect trainer for me.. However, I have seen a lot of discussion with the cadence lagging and stalling on Zwift.. This would drive me nuts if a firmware update doesnt fix it.. I guess my options would be to use my Wahoo external Cadence sensor or Quarq PM as the cadence sensor on Zwift.

Did you experience the cadence issues that GPLama and DC Rainmaker had with cadence?

[TobinHatesYou]

My original Hammer is within 1% of both a DZero and Assioma Duos on my trainer bike. The only deviation is at sprint wattages combined with high flywheel speeds where it measures slightly high. The thing I’ve noticed about the Saris trainers is the consistency in measurement between different units. Neos and KICKRs can vary quite a bit.

The H3 will measure 1-1.5rpm low because it’ll miss some accelerations. Other than that I haven’t experienced major issues. When you sprint really hard and the flywheel is still buzzing, there won’t be any torque going through the chain if you’re spinning the pedals, but not engaging the freehub. This will result in 0rpm being reported, but that’s not a huge issue. You can always just pair your PM or an individual cadence sensor instead.

[TheRich]

So you have a smart Trainer with a power meter like a Kickr or Tacx, and still use the PM on your bike when on Zwift? If so, why did you decide to do it? For consistency when riding outdoors and indoors? Or do you feel your Trainer PM isnt as accurate?

thank you

The data from a PM could go to a head unit to something like GC or WKO while trainer data goes to Zwift and Strava. But if you're not doing that, it's easier to just disregard PM data.

My last ride had a 1.5% power difference and a 1 rpm difference in cadence between an H3 and Vector pedals. Well within an acceptable margin of error.

TheRich, The Saris H3 seems like the perfect trainer for me.. However, I have seen a lot of discussion with the cadence lagging and stalling on Zwift.. This would drive me nuts if a firmware update doesnt fix it.. I guess my options would be to use my Wahoo external Cadence sensor or Quarq PM as the cadence sensor on Zwift.

Did you experience the cadence issues that GPLama and DC Rainmaker had with cadence?

It does lag a little, just like power gets smoothed a little.

I haven't seen what they're referring to and although I like looking at data, cadence isn't something I care about. It kinda is what it is, and due to the feel of a trainer, I don't ride at the same cadence as outside anyway. Using the trainer as the data source for everything just seems easier, so that's what I do.

It's my first smart trainer, seems quiet enough and haven't had a probem but it really comes down to availability and pricing.

[gSporco]

My original Hammer is within 1% of both a DZero and Assioma Duos on my trainer bike. The only deviation is at sprint wattages combined with high flywheel speeds where it measures slightly high. The thing I’ve noticed about the Saris trainers is the consistency in measurement between different units. Neos and KICKRs can vary quite a bit.

The H3 will measure 1-1.5rpm low because it’ll miss some accelerations. Other than that I haven’t experienced major issues. When you sprint really hard and the flywheel is still buzzing, there won’t be any torque going through the chain if you’re spinning the pedals, but not engaging the freehub. This will result in 0rpm being reported, but that’s not a huge issue. You can always just pair your PM or an individual cadence sensor instead.

Thank you... your explanation makes perfect sense to why deviation occurs

[gSporco]

It does lag a little, just like power gets smoothed a little.

I haven't seen what they're referring to and although I like looking at data, cadence isn't something I care about. It kinda is what it is, and due to the feel of a trainer, I don't ride at the same cadence as outside anyway. Using the trainer as the data source for everything just seems easier, so that's what I do.

It's my first smart trainer, seems quiet enough and haven't had a probem but it really comes down to availability and pricing.

Overall how does the Saris H3 compare to actually riding outside? I know none of them are perfect and wont feel exactly like riding outaide, but from what I am reading the Saris H3 is supposed to feel the best

[TobinHatesYou]

It certainly feels better than a Neo, which I can only describe as very “digital.” Anecdotally, I’d say it feels better than a 2017 KICKR too, but the newer versions have a slightly bigger flywheel than before. I wouldn’t say anything feels like outside...The H3 does not have any built-in side-to-side flex and at certain flywheels speeds you can sort of feel some kind of resonant vibration, like a very fine washboard effect. I suspect all belt driven trainers have this.

[gSporco]

It certainly feels better than a Neo, which I can only describe as very “digital.” Anecdotally, I’d say it feels better than a 2017 KICKR too, but the newer versions have a slightly bigger flywheel than before. I wouldn’t say anything feels like outside...The H3 does not have any built-in side-to-side flex and at certain flywheels speeds you can sort of feel some kind of resonant vibration, like a very fine washboard effect. I suspect all belt driven trainers have this.

Awesome.. I got all my questions answered today

[saldegracia]

I've had an Elite Rampa smar trainer, and now an Elite Suito. Apart from the issues with the Suito that I have written about in another thread power measurements have always been off (too high on both trainers) compared to the 4iiii and Stages PMs on my road bikes. So I just started using the bike PM with Zwift, works just as well as the trainer power and there are no issues with different power readings on outdoor/indoor rides.

[TobinHatesYou]

Well here's the thing. If you're using left-only 4iiii or Stages PMs, then you don't know if you have a L/R imbalance. If you are using L/R PMs from either manufacturer, the right-side crank will read ~7% low, causing the total power to be reported ~3.5% low.

The Rampa is bad though.

[Lozaen]

The data from a PM could go to a head unit to something like GC or WKO while trainer data goes to Zwift and Strava. But if you're not doing that, it's easier to just disregard PM data.

My last ride had a 1.5% power difference and a 1 rpm difference in cadence between an H3 and Vector pedals. Well within an acceptable margin of error.

You can also connect a headunit vai ANT+ to a smarttrainer and bluetooth for zwift. Not sure if this works with all smarttrainers, but the Elite Suito for example supports this.
I tried to use the powermeter pedals as powersource on zwift and the trainer as controlable....works, but causes a bit of delay.
Personally the Powermeter Link function worked for me, but since i have to switch pedals regularly, I chose to use normal pedals on the smart trainer and use every 4 to 6 weeks for a single session the Assiomas to cross check whether or net the smarttrainer is still in range....less hassle and good responsiveness during exercising.