why clincher more pricey???

[Spinnekop]

my nipples on the outside and I don't feel at all disadvantaged by them.

 

 

 

I am NOT even goin to try to reply........

 

[Johan Bornman]

OK, this is an interesting calculation.

 

I need the following please.

 

1) Mass of rider plus bike without wheels

2) Mass of wheels with nipples at rim

3) Mass of nipple at-hub-saving. (In other words, tell me how much the nipples at the hub weigh, minus their substitute devices at the rim).

4) Magnitute of accelleration.

5) How many times you'd like me to make you accellerate in a race and how much each time.

 

Think about his and I'll plug the values into the formula and we can see if it is all marketing bull or not.

 

 

[Spinnekop]

OK' date=' this is an interesting calculation.

 

I need the following please.

 

1) Mass of rider plus bike without wheels  75kg + 6.8kg - 1.3kg (Boras)

2) Mass of wheels with nipples at rim 1.3kg

3) Mass of nipple at-hub-saving. (In other words, tell me how much the nipples at the hub weigh, minus their substitute devices at the rim).

all else stay equal?  Cant cuase the complete rim will be less due to manufacturing and components being diffent, thus the PACKAGE is diffent........but I leave that up to you.......(890g - LEW Clinchers.)

4) Magnitute of accelleration.  1000watt

5) How many times you'd like me to make you accellerate in a race and how much each time. 23 attacks thrown and countered and followed at the 94.7

 

Think about his and I'll plug the values into the formula and we can see if it is all marketing bull or not.

 

 

[/quote']

 

Let me know......

[Johan Bornman]

1) Mass of rider plus bike without wheels  75kg + 6.8kg - 1.3kg (Boras) Check

2) Mass of wheels with nipples at rim 1.3kg check

3) Mass of nipple at-hub-saving. (In other words, tell me how much the nipples at the hub weigh, minus their substitute devices at the rim).

all else stay equal?  Cant cuase the complete rim will be less due to manufacturing and components being diffent, thus the PACKAGE is diffent........but I leave that up to you.......(890g - LEW Clinchers.) OK, lets say the nipple configuration changes the wheel by taking 100 grams away from the rim and puts it at the hub.

4) Magnitute of accelleration.  1000watt  This is a unit for work. I want meters per second per second or... kph per second.  Or, zero to X kph in Y seconds.

 

 

5) How many times you'd like me to make you accellerate in a race and how much each time. 23 attacks thrown and countered and followed at the 94.7 OK, but from what speed to what speed did you accellerate.

 

 

Johan Bornman2008-11-28 04:43:03

[Marius]

I just looked, when attacking it's no more than a 15km/h increase in speed during races and it's only for a few seconds. But Iets see what Spidey says. At Killarney we'd go from 41km/h to about 51km/h for a few secs when attached. At races the speeds seems much slower, from about 32 to 43 I see a lot.

[Johan Bornman]

I just looked' date=' when attacking it's no more than a 15km/h increase in speed during races and it's only for a few seconds. But Iets see what Spidey says. At Killarney we'd go from 41km/h to about 51km/h for a few secs when attached. At races the speeds seems much slower, from about 32 to 43 I see a lot.[/quote']

 

OK, that makes sense, but I need to know how much time it takes you to go from 41 to 51 seconds.

 

 

Johan Bornman2008-11-28 04:45:37

[linnega]

aha...thought so...but realy' date=' does that lip realy cost R2000 rand more to make...that seems a bit much [/quote']

R2000 seems a bit much for a decent set of clinchers.  Even factory built Khamsins or Ventos cost less than that (at real world prices not J&J RRiP-off)

[Spinnekop]

To mention one or two or three

33 to 63km/h in 490m @ 1.1% gradient - 30sec

36 to 72km/h in 900m @ -4.3% gradient - 55sec

34 to 67km/h in 800m @ -3.5% gradient - 55sec

30 to 76km/h in 900m @ -4% gradient - 65secSpinnekop2008-11-28 04:51:45

[Spinnekop]

Updated done.

Spinnekop2008-11-28 04:53:57

[linnega]

To mention one or two or three

33 to 63km/h in 490m @ 1.1% gradient - 30sec

36 to 72km/h in 900m @ -4.3% gradient - 55sec

34 to 67km/h in 800m @ -3.5% gradient - 55sec

30 to 76km/h in 900m @ -4% gradient - 65sec

My legs are sore just thinking about the first one.

[Marius]

yeah, also get 30s

[AndreZA]

I think the answer to this is either 42, or C.

 

 

[Johan Bornman]

To mention one or two or three

33 to 63km/h in 490m @ 1.1% gradient - 30sec

36 to 72km/h in 900m @ -4.3% gradient - 55sec

34 to 67km/h in 800m @ -3.5% gradient - 55sec

30 to 76km/h in 900m @ -4% gradient - 65sec

 

Hey, I've gone offline and did some calculations based on these figures. Did you edit the figures?

 

Are these actual values read off a PowerTap or GPS or something? Can I trust them?

 

Also, I'm am going to average out your accelleration and then do the calculation based on a test case of 24 accellerations in the race, based on the weights you gave me but on the average of the accellerations showed here.

 

 

[Spinnekop]

I can mail you the Polar file if you want to..........?

[Johan Bornman]

OK, I think your averages vary far too much. If I work with these I have to ask you how much you accellerated for each attack from 1 to 24. Too much work. Give me an average attack speed and lets pretend on this race the attacks were all equal.

 

Scenarios (actual data)	Time (s)	Acc m/s2
Scenario One 33 to 63 in 30 sec	20	0.277778
Scenario Two  33 to 67 in 55 sec	25	0.171717
Scenario Three 36 to 72 in 55 sec	30	0.186869
Scenario Four  30 to 76 in 65 sec	35	0.324786

 

 

Have a look at the far right colum. This is accelleration for the said scenario in m/s/s or m/s2

 

Choose one and we go with that.

 

 

[Johan Bornman]

I can mail you the Polar file if you want to..........?

 

No thanks, I won't know what to do with it. I believe you, I just want to know if it was measured with some trusted instrument. It is very difficult to measure accelleration using only a stopwatch and a bike computer. The computer's latency is huge - something like 5 seconds on a Polar for the display and of course, whatever the recording interval was set at.

 

However, if this data was taken with Polar's auto record feature we can't trust the data because it was only recorded once every five seconds at best. That's why I asked what instrument was used.