see highlighted. It looks like @Crownan was correct, but BKool doesn’t specify what “minimum speed” is. Perhaps someone else can find it. Obviously shifting down will help to a point so I guess my advice would be, use whatever gearing works with the minimum power you use because it should also work for the upper end as well.
I have a bkool pro 2 (no idea if there’s any difference from the original to the 2) and no problems so far.
With an FTP of 203, most workouts have rests around 80-100w, and it adapts to my cadence just fine.
I never tried going below 80… maybe then i would have some problems.
For exemple today workout:
Target 180 cadence 110
Target 70 cadence 70… below 70 i wasn’t able to reach the target… over 70 the power was over the taget…
You have to downshift. Also in erg mode. 70 watt is a very low value.
I have the bkool smart pro 2. During my workouts I use always the same gear: small in the front and in the middle on the rear (36-17).
With this gear I can practice any kind of workout. Going under 100w I have to downshift.
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I would like some more discussion on the excerpt above if anyone is still interested.
Basically I have found that there is big difference (much harder) doing sweet spot intervals in middle back and middle front than large front and middle back, certainly more than 10 Watts, on my old 9 speed triple front TCR… combined with TrainerRoad and Wahoo KickR … My perception is backed up by Heart Rate levels. The 10 Watts is an estimation, but I believe it is actually more. Intervals 3x10 200 Watts Cadence 90-95 RPM
Using the ERG setting…!!
We covered this in depth here:
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There is lots of argument about this - I just go for the same gear I do my Ramp test in so I’m training with the same set up and the straightest chain which is I think on my Sora equipped 9 speed turbo bike 50/17 as it has a compact chainset and this gear is the middle cog. Simples!
Thanks Chad… that was near enough what I was looking for and then some… I think you advised more than once that one should try to replicate indoor what one wants to achieve out… To that end I will try to see what power I can sustain at a cadence of of between 70-80 RPM for various intervals to improve my climbing… thanks again Larry
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If I may : I understand how ERG Mode works and yet, it still doesn’t work the way it should (I think?).
Let me clarify :
I use a Tacx Flux 2 and do trainings with ERG Mode on with Zwift (I’m a noob my FTP is 150).
If I use my 2nd, third, or fourth large cog, it mostly works okay-ish, meaning when I warm up at 85 Watt it’s mostly running at 95 Watts (cadence 90) and when I’m supposed to be at 125 it’s usually going around that power pretty fairly.
When I have short intervalls (such as yesterday) of 255Watts, it takes some time. Sometimes it’s about a second or 5 before it really kicks in, sometimes longer.
So my feeling is that it kinda works and that there are some limitations and it’s not perfect.
But here comes the catch: If I try starting my workout on the higher gears (2nd in front and about 2nd or 3rd smallest in the back for example) I’m pushing 180 watts in warm up and it just doesn’t adjust at all.
Note that I’m holding a steady cadance of 80 during that time in the hopes that it would drop to the necessary power output thanks to ERG, but it just doesnt.
The last test I’m going to do is try a different software (Tacx or something else) than Zwift. Because from what I’ve been reading, it’s not my Tacx, or at least I hope it’s not.
You are experiencing a wattage floor issue, that is present based on your specific trainer.
This is a known issue with the Flux series and many similar mid to low level smart trainers. The floor (and ceiling of upper power limits) exist and force a user to shift to hit the actual lows or highs in their workouts.
Your issue with a low absolute FTP value means you need to spin a smaller gear, to keep the trainer spinning slower to hit the low wattage. This works fine and will only limit you when you need to hit extra high wattage. In those cases, you may find that you need to shift to a faster gear to get those values, even in ERG mode.
So, everything is “working right” but you are experiencing less than desired results because of the hardware limitations.
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Oh, that does explain things in the lower watt ranges!
Thanks for the information!
Is it possible that a similar thing happens when I use a harder gear while only needing to achieve 125 watts for example?
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If you mean that in high gearing that the trainer has trouble getting below 125w, then yes. That is likely the reason. You have hit the “wattage floor” for the trainer, gearing and cadence you are applying.
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In order to get lower wattage, you are forced to shift down to a lower gear and wheel speed.
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It’s more that when I use a higher gear and have to hit 125 Watts, I’m pushing 160-200 on the same cadence and the trainer doesn’t adapt in order to hit 125 output.
It feels as if the trainer is unable to go to that kind of low power while hitting 90 cadence on high gear.
is that possible or might I be facing some other issue?
- Yes, it’s possible and exactly what I described in the post immediately above.
You HAVE TO SHIFT into an easier gear on those recovery steps. Your trainer is unable to handle very high and very low wattage in the same gearing.
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Ok thanks a lot for the info guys!
Much appreciated
For anyone reading this who use a wheel-on trainer, the wattage floor and ceiling limits also come into play. This is due to high wheel speed. If you are overpowering your trainer (it doesn’t provide enough resistance) change to an EASIER gear. This will slow the wheel down and the trainer can (usually) provide the correct resistance. Note that this has no effect on your training; you still have to output the required watts using the easier gear.