Team BKool CycleChat

[bridgy]

I was in the velodrome yesterday and was cruising around at abut 55kph, pushing around 480 watts or so. However I then started to push around 850 watts and the speed only went up to around 80 kph. Dropping back to 40kph I was using only 250 watts. So this is definitely not a linear progression in a power/speed graph. This would indicate that there is an increase in resistance (in this case wind resistance) the faster you go. Otherwise if I double the power, I would double my speed.
Don't forget that Power = Force x Velocity
Or, Velocity = Power/force
Now, force = mass x acceleration
So, velocity = power/(mass x acceleration)
If there were no adjustments to resistance, this would mean that the accelerative force would remain the same. The mass would also be the same (although some of us can sweat out a fair amount!). Therefore you would have a linear graph of increased power being directly proportional to the resultant velocity, which I do not think is the case.
It may be that the additional resistance added due to higher velocity is too little at the top end. The power/speed graph should be exponential and it is quite possible that this curve is too shallow, which I think is what @bridgy is implying. It may be that they need to adjust their algorithm slightly in this respect which would be more representative of the greater effect of wind resistance.

Make sense?

Yes - this is what I mean! As I've got fitter and been able to go faster for longer, the speed and (bkool) watts have got less realistic. I don't think the resistance has changed though - it feels about the same.

 

[AAAC 76C]

still waiting for the thingamyjig to put the cassette on

SoarerV8?

 

[AAAC 76C]

Even weirder then! I only had the option of the map view or just the profile so I was never in 3d!

Subscription due Bridgy?

 

[bridgy]

Subscription due Bridgy?

No - I did check that!!

 

[AAAC 76C]

I was in the velodrome yesterday and was cruising around at abut 55kph, pushing around 480 watts or so. However I then started to push around 850 watts and the speed only went up to around 80 kph. Dropping back to 40kph I was using only 250 watts. So this is definitely not a linear progression in a power/speed graph. This would indicate that there is an increase in resistance (in this case wind resistance) the faster you go. Otherwise if I double the power, I would double my speed.
Don't forget that Power = Force x Velocity
Or, Velocity = Power/force
Now, force = mass x acceleration
So, velocity = power/(mass x acceleration)
If there were no adjustments to resistance, this would mean that the accelerative force would remain the same. The mass would also be the same (although some of us can sweat out a fair amount!). Therefore you would have a linear graph of increased power being directly proportional to the resultant velocity, which I do not think is the case.
It may be that the additional resistance added due to higher velocity is too little at the top end. The power/speed graph should be exponential and it is quite possible that this curve is too shallow, which I think is what @bridgy is implying. It may be that they need to adjust their algorithm slightly in this respect which would be more representative of the greater effect of wind resistance.

Make sense?

You are experiencing an increase in form drag (aerodynamics) which is proportional to 1/2 x coefficient of drag x velocity squared.
Not quite exponential but it is an ever increasing curve.
I doubt that they make any changes for change in direction (acceleration) as you round the bends but on the whole I think the velodrome speeds and power are all a bit suspect but good for warm ups and intervals.
All sorts of other factors involved but that is the main reason for the lesser increase in speed for power as you get faster.
One of the reasons why there are not huge differences on the top speed of most road cars but a big difference in 0 to 60 times.
By the time you approach 150 mph the form drag is huge in proportion to other factors an so it takes a awful lot more power to make relatively small differences in top end.

 

[Monte]

Thankfully only doing a recovery session this evening, but the bsim was struggling - I started off in 3D, then it kept going offline & online all the way through the session but like Bridgy's session the only view I had was map view.

The route was this Thursday chaingang ride so hopefully it will sort itself out

 

[bobinski]

It did, all unpacked but still waiting for the thingamyjig to put the cassette on .

SoarerV8?

His man servant!

 

[AAAC 76C]

Both! Obviously the watts are nonsense. I am starting to have a theory on these increasingly high watts - particularly on flat courses like this. I think if you're a powerful enough rider to overcome the resistance the trainer sets you get exponentially more "bkool watts". I don't know the physics well enough to explain exactly what I mean but I know in real life you're mostly fighting wind resistance, and the faster you go the harder it gets (someone else can hopefully explain this more technically!). But in bkool, the resistance is fixed, based on what the algorithm decides for your weight and the slope etc, and if you go faster and faster, it doesn't get harder and harder as it would in real life, it just keeps the same resistance. And I don't think the speed and watts algorithm takes account of this so just allows you to go faster and therefore show higher and higher watts. I think it's ok up to a certain amount of (real) power but falls apart a bit over a certain amount. That's my theory if it makes any sense....?

As I said a couple of days ago I think the software confuses itself because of the delays they have added.
If the conditions change before the delay finished it skips that condition (in this case slope) and moves on to the next and starts another delay but at this time you have lost no speed. If you find yourself in one of these 'loops' and you slow down everything seems to go back to normal but there are some courses that seem to bring out this anomaly more than others.
You have been there before, LB has reported this finding and I felt that a few of the early Summer Cup rides were like that this year.
I even think the Chaingang stage 1 or 2 was one of these because I was hammering along at 56 kph with 264 watts showing at times.
On the flat we should be able to go up to the full force of the 1200 watts resistance but perhaps they have messed with that as well

 

[Perky77]

Evening all,
Apologies for being off line for the past week, my man flu then changed to a sickness bug bought home by our lovely children as an early Christmas present.

Today is first day I've felt semi human. I can't see me getting back on until Wednesday at the earliest as I want to make sure I'm completely recovered

 

[Perky77]

@CXRAndy do you have any more codes for a months free training with traineroad? I'm tempted to try it in preparation for Colli Nove at the end of May

 

[Soarerv8]

SoarerV8?

Been called many things but never a thingamajig. That being said do find it quite endearing.

 

[AAAC 76C]

I was in the velodrome yesterday and was cruising around at abut 55kph, pushing around 480 watts or so. However I then started to push around 850 watts and the speed only went up to around 80 kph. Dropping back to 40kph I was using only 250 watts. So this is definitely not a linear progression in a power/speed graph. This would indicate that there is an increase in resistance (in this case wind resistance) the faster you go. Otherwise if I double the power, I would double my speed.
Don't forget that Power = Force x Velocity
Or, Velocity = Power/force
Now, force = mass x acceleration
So, velocity = power/(mass x acceleration)
If there were no adjustments to resistance, this would mean that the accelerative force would remain the same. The mass would also be the same (although some of us can sweat out a fair amount!). Therefore you would have a linear graph of increased power being directly proportional to the resultant velocity, which I do not think is the case.
It may be that the additional resistance added due to higher velocity is too little at the top end. The power/speed graph should be exponential and it is quite possible that this curve is too shallow, which I think is what @bridgy is implying. It may be that they need to adjust their algorithm slightly in this respect which would be more representative of the greater effect of wind resistance.

Make sense?

DP, have a play with this, it only goes up to 500 watts which would normally be fine for mortals.
http://bikecalculator.com/
Based on the info in this calculator I think BKool is very optimistic in the velodrome.
And based on papers like this I think we are getting granted too much power:
Racing cyclist power requirements in the 4000-m individual and team pursuits.
Broker JP1, Kyle CR, Burke ER.
Author information

• 1USOC Sport Science & Technology Division, and University of Colorado at Colorado Springs, USA.

Abstract
PURPOSE:
The purpose of this paper is: 1) to present field test data describing the power requirements of internationally competitive individual and team pursuiters, and 2) to develop a theoretical model for pursuit power based upon on these tests.

METHODS:
In preparing U.S. cycling's pursuit team for the 1996 Atlanta Olympics, U.S. team scientists measured cycling power of seven subjects on the Atlanta track using a crank dynamometer (SRM) at speeds from 57 to 60 kph. By using these field data and other tests, mathematical models were devised which predict both individual and team pursuit performance. The field data indicate the power within a pace line at 60 kph averages 607 W in lead position (100%), 430 W in second position (70.8%), 389 W in third position (64.1%), and 389 W in fourth position (64.0%). A team member requires about 75% of the energy necessary for cyclists riding alone at the same speed. These results compare well with field measurements from a British pursuit team, to recent wind tunnel tests, and to earlier bicycle coast down tests.

RESULTS:
The theoretical models predict performance with reasonable accuracy when the average power potential of an individual or team is known, or they may be used to estimate the power of pursuit competitors knowing race times. The model estimates that Christopher Boardman averaged about 520 W when setting his 1996, 4000-m individual pursuit record of 4 min 11.114 s and the Italian 4000-m pursuit team averaged about 480 W in setting their record of 4:00.958. Both used the "Superman" cycling position.

 

[Daddy Pig]

DP, have a play with this, it only goes up to 500 watts which would normally be fine for mortals.
http://bikecalculator.com/
Based on the info in this calculator I think BKool is very optimistic in the velodrome.
And based on papers like this I think we are getting granted too much power:
Racing cyclist power requirements in the 4000-m individual and team pursuits.
Broker JP1, Kyle CR, Burke ER.
Author information

• 1USOC Sport Science & Technology Division, and University of Colorado at Colorado Springs, USA.

Abstract
PURPOSE:
The purpose of this paper is: 1) to present field test data describing the power requirements of internationally competitive individual and team pursuiters, and 2) to develop a theoretical model for pursuit power based upon on these tests.

METHODS:
In preparing U.S. cycling's pursuit team for the 1996 Atlanta Olympics, U.S. team scientists measured cycling power of seven subjects on the Atlanta track using a crank dynamometer (SRM) at speeds from 57 to 60 kph. By using these field data and other tests, mathematical models were devised which predict both individual and team pursuit performance. The field data indicate the power within a pace line at 60 kph averages 607 W in lead position (100%), 430 W in second position (70.8%), 389 W in third position (64.1%), and 389 W in fourth position (64.0%). A team member requires about 75% of the energy necessary for cyclists riding alone at the same speed. These results compare well with field measurements from a British pursuit team, to recent wind tunnel tests, and to earlier bicycle coast down tests.

RESULTS:
The theoretical models predict performance with reasonable accuracy when the average power potential of an individual or team is known, or they may be used to estimate the power of pursuit competitors knowing race times. The model estimates that Christopher Boardman averaged about 520 W when setting his 1996, 4000-m individual pursuit record of 4 min 11.114 s and the Italian 4000-m pursuit team averaged about 480 W in setting their record of 4:00.958. Both used the "Superman" cycling position.

If you look at the velo one hour record, Wiggins would have been left behind! So yes, we are all getting a boost in watts (and self esteem).

 

[Daddy Pig]

Not sure that calculator is entirely accurate. Wiggo would have to put out around 900 watts in his 1 hour record based on the output.

 

[CXRAndy]

@CXRAndy do you have any more codes for a months free training with traineroad? I'm tempted to try it in preparation for Colli Nove at the end of May

Sorry Perky, it was snaffled up off here by one of our 'esteemed' members. Maybe if i'm a good boy i'll get another. You can also buy it on a monthly basis for$12 and cancel when you finish a course/workout group.