Spinning

I recently changed from a Tacx Neo to a kicker Core however what i find rather annoying on the software or may be the core itself.

If I am doing a big power session then the app then changed from way 100rpm 300w to 90rpm 90w then i am cycling fresh air and the app show 0rpm until my peddles catches up with the app if that sort of makes sense.

I never had this issue on the Tacx or am i missing something, this is all in erg mode

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Yes, I have this problem with the Kickr Core, as well.

The Kickr seems to require power >0 for it to register any cadence. I don’t the exact technical reasons, but I have noticed this. So, when you make a huge drop in power, even tho you are still spinning quite quickly, it won’t register your cadence until the flywheel spins down far enough to begin registering above 0w power, again.

To get around this, I have a Wahoo Cadence sensor on my pedals and I use that instead of the trainer’s cadence.

I wonder if someone could explain the technical reasons. I’m assuming it has to with certain pieces not spinning when there’s no pressure on them?

Hi folks.

The reason a Neo works ok is that the Neo has a small sensor on one side that is looking for a crank passing over it. So whether you’re loading a crank or not after a high power effort, if you’re still spinning, then you’ll still have a cadence.

I’m not as close to the Kickr’s but I think they’re using force through cranks to measure cadence and while the trainer is catching up (eg flywheel slowing down I guess and in some trainers the virtual flywheel) there won’t be any differentials in pedal stroke for the trainer to measure.

The only way to do this ‘properly’ is to use a cadence sensor (on any trainer … even Neo’s).

You can even fool the Tacx Neo’s - put a MTB on with a different geometry and say slightly shorter cranks and the crank arm doesn’t pass close enough to the main trainer unit and you get ‘occasional’ duff readings. For that scenario ((I’ve done this)) we just tape a paper clip to the end of the crank. Bodging is great.

Hi @timboe I experienced the cycling in fresh air on a big power drop until I changed to always using the small front ring in erg mode. This means that the trainer is quicker to respond. If it’s a really big drop then backing off on the power applied to the pedals a fraction of a second before the drop will help too

Like @emacdoug I still use the Wahoo cadence sensor as it seems more accurate than my Kickr apart from at very low cadences when it drops to zero

@genolan Yeah, I’ve had that problem, too. Usually on GOAT if I get down around 55rpm.

I have just changed my ring on the bike will be going for a session later will report back how it goes.

I recently had a discussion with Wahoo support about this. There doesn’t seem to be an official ‘lowest RPM’ it can detect, but I was told that crank mount is more reliable than shoe mount. My experience testing it matched that - with the sensor shoe mounted, reported cadence would often drop to zero below 55 RPM. Crank-mounted, I could reliably get down to about 30 before it would drop out.

On the other end, I was also told that the sensor has an official upper limit of 180 RPM (which I didn’t see in any documentation), though the only time I’ve ever run into that limitation is when doing cadence build drills.

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Well i tried it and yes it is better on a smaller ring still not great but better, i also changed my cadence to my power meter crank.

Thanks for the help

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This makes sense to me and is in line to my experiences with it. I have it zip-tied to my left crank. It’s more reliable than using the kickr core’s cadence and 60-130rpm’s cover 99% of my usage, anyway - except for the cadence drill vids and GOAT/Power Station.