Team BKool CycleChat

[Monte]

It has an accurate power meter, bkool over reads by 40-50 watts for me. Oh and cost, its a lot more than a bkool pro

Interesting...

Hi Geoff I have done the Tin can again on a Bkool pro for comparison

Wahoo Kickr
Power (watt) 290.2
Time 27.50
Ave Speed 23.1 mph

Bkool Pro
Power 302 Watt
Time 25.16
Ave Speed 25.4 mph

I tried to be consistent with effort. The bkool registers more watts on the flatter sections and has a smoother speed profile compared to the kickr
Oh I didn't have a flying start on the Bkool, I registered 82mph off the line with the kickr

Thanks for sharing, I still think about buying a kickr but must admit i'm happy with my bkool unit at the moment (since I completely stripped it down and put it back together again) and it works really well with the bsim software. I have a powertap hub meter on my road bike and depending on the type of course, ie. flatter rides or undulating courses I think it gives a close reflection to my actual fitness and close to my powertap readings. The only time I would question the power numbers generosity is on some of the mountain goat stages where I'm not sure I would be able to average 300 watts on a hour long hill ??? don't know as being a larger rider I don't go looking for too many hills in real life, lol.

 

[BILL S]

Great. I guess we''ll never know what problem Bkool had but glad it's sorted!

Wow Bob, that was a bit close! Shame we didn't start at the same time, would have been a good battle

Just what I was thinking. I think Geoff accidentally had me and Bob mixed up with our start times.

edit: Which would add the additional excitement of you guys having to chase me down.

 

[bridgy]

No drawbacks, at all. The kickr is extremely stable, doesn't wobble unlike the Bkool Pro, which can feel like its about to topple unless you keep upper body still whilst off the seat. Obviously no wheel-spin-direct drive. Downside, its is disadvantaged against the pro for speed, so not a level field for competing. It has an accurate power meter, bkool over reads by 40-50 watts for me. Oh and cost, its a lot more than a bkool pro

We know that for the Pro, Bkool takes the speed of the wheel and converts that into a power figure - as the Kickr has a power meter do you know if for that, the Bkool sim takes the Kickr's power reading and converts it to speed, so doing the opposite as for the Bkool pro trainer?

 

[BILL S]

Did the Mountain Goat stage that I failed to complete last time, and so nearly blew up several times.
I then go look at the league in question and see that the next one is steeper and longer...

That's a good thing that you did. Don't know if you noticed that I'd added an hour and a half to your 30 min blast so your time for that first stage was 2 hours . I wondered if you'd see that and be persuaded to do the whole thing.

My motivational techniques are a bit old school I must admit

 

[BILL S]

Chaingang tonight at 7pm is West Lothian. Hopefully flat as a pancake but I doubt it.
10 mins warmup, no password.

 

[BILL S]

Yep, accepted and league now showing 11 results.

I'm having the same problem accepting GG's West Lothian Chaingang ride. Just get an error message, but hopefully that'll fix itself as per Bob's ride.

 

[gbrown]

We know that for the Pro, Bkool takes the speed of the wheel and converts that into a power figure - as the Kickr has a power meter do you know if for that, the Bkool sim takes the Kickr's power reading and converts it to speed, so doing the opposite as for the Bkool pro trainer?

I don't believe this is the case.

Bkool doesn't know if the power figure is accurate or not, whether the trainer has an actual power meter or is just broadcasting estimated power over ANT+ FE-C.

Therefore, I would guess that Bkool just take the speed figure from whichever trainer and feed it into their algorithms.

One way to validate this would be to ride with a KICKR and compare the bkool power to the KICKR power from, say, a garmin. I am sure when I have done this in the past, the power has varied between the garmin and bkool, therefore bkool must be using the speed to calculate their own power.

I think the speed difference Andy saw between similar efforts on the KICKR and the bkool pro is down to the better calibrated resistance on the KICKR. When a certain resistance is required, the KICKR is much more likely to get close to that resistance, the bkool is bound to vary more, and is much more likely to undershoot on the resistance, thereby allowing you to achieve a slightly higher speed. This is then used to calculate a slightly higher power reading.

Geoff

 

[bridgy]

I don't believe this is the case.

Bkool doesn't know if the power figure is accurate or not, whether the trainer has an actual power meter or is just broadcasting estimated power over ANT+ FE-C.

Therefore, I would guess that Bkool just take the speed figure from whichever trainer and feed it into their algorithms.

One way to validate this would be to ride with a KICKR and compare the bkool power to the KICKR power from, say, a garmin. I am sure when I have done this in the past, the power has varied between the garmin and bkool, therefore bkool must be using the speed to calculate their own power.

I think the speed difference Andy saw between similar efforts on the KICKR and the bkool pro is down to the better calibrated resistance on the KICKR. When a certain resistance is required, the KICKR is much more likely to get close to that resistance, the bkool is bound to vary more, and is much more likely to undershoot on the resistance, thereby allowing you to achieve a slightly higher speed. This is then used to calculate a slightly higher power reading.

Geoff

Thanks Geoff - that makes sense. Would another way to test it be too just to stop pedaling on a flat or descent and see what the power reading says - the bkool continues showing a reasonably high power figure for quite a while, and gradually falls with the speed, even if you're not pushing the pedals which I presume an actual power meter wouldn't do?

There's much more variation for the setup on a Pro (tyre size/type/pressure) than a Kickr too. I suppose it would probably be a much more level playing field if we were all on Kickr's rather than Bkool Pro's!

 

[CXRAndy]

Geoff, you will know from experience the Kickr power and speed drops off rapidly if you ease up at all. The bkool does hold the numbers longer. You can see just from the graph profile how jagged the Kickr is compared to the Bkool Pro. Maybe this is where the higher average speed comes from.

 

[bobinski]

Hi Geoff I have done the Tin can again on a Bkool pro for comparison

Wahoo Kickr
Power (watt) 290.2
Time 27.50
Ave Speed 23.1 mph

Bkool Pro
Power 302 Watt
Time 25.16
Ave Speed 25.4 mph

I tried to be consistent with effort. The bkool registers more watts on the flatter sections and has a smoother speed profile compared to the kickr
Oh I didn't have a flying start on the Bkool, I registered 82mph off the line with the kickr

.

I will take that Kickr!

Just what I was thinking. I think Geoff accidentally had me and Bob mixed up with our start times.

edit: Which would add the additional excitement of you guys having to chase me down.

Sounds good Bill. I suspect you will find power and speed to keep us at bay. Mind you, I won't have done an energy sapping Zwift ride immediately before...just saying

 

[JLaw]

Geoff, you will know from experience the Kickr power and speed drops off rapidly if you ease up at all. The bkool does hold the numbers longer. You can see just from the graph profile how jagged the Kickr is compared to the Bkool Pro. Maybe this is where the higher average speed comes from.

Yup. You lay off the pedals, watts plummet within a couple seconds and with the new sim you can see speed react accordingly.

 

[<Tommy>]

I'm not around tonight, my backs still not right. Hopefully I'll be better for the weekend. I've not ridden in a couple of days and I'm getting withdrawal symptoms.

 

[bobinski]

I'm not around tonight, my backs still not right. Hopefully I'll be better for the weekend. I've not ridden in a couple of days and I'm getting withdrawal symptoms.

TT get the kids to walk on your back and then take a hot bath! You will be right as rain

 

[CXRAndy]

TT get the kids to walk on your back and then take a hot bath! You will be right as rain

If it's muscle pull, I find deepheat and painkillers so I can keep moving. I haven't often had a bad back but on the few occasions where I couldn't get relief. I went back to the gym and just did light workouts for a week or two and my back issues cleared up. Hang from a pulllup bar if you can hold your weight. No cyclist arms please

 

[theboxers]

Osteopath for me. Every 18 months to 2 yrs. Stems from a back injury at 16. One visit is usually enough and I mostly catch it before it becomes a major problem.

Part of the reason I ride bikes and motorbikes. It keeps my back moving and flexing. Sitting in an office or car all day is what normally kicks off an episode.