I saw the link with claims about the bontrager winged tire:
http://reviews.roadbikereview.com/...worlds-fastest-tire/
The relevant information is:
Very interesting to see that at low windspeeds (15 mph), where Crr would be dominant - that the
bontrager tests so close to the veloflex record. (Care to comment on that Al? Tom?)
I find that interesting, to say the least.
I talked to HED, and they said that their aero charts for the H3 clincher were produced with the Bonty TT tire above. And that they observed about a 20 gram differential over the Mich 23. Bontrager seems to see more than double that from
the chart above.
I understand that a great tire can make a wheel great ... but it is hard for me to believe at 30 mph, there is a 50
gram differential (or about 5 1/2 watts) due mostly to the "wing" (I guess - or some mysterious Cd shape problem) over the veloflex - which starts out about the same.
And with regards to the other tires - all the other non-winged tires seem to maintain a consistent gap at higher speeds (???!!!)..which is strange, since you'd think the advantage of the wing would come into play. ( assuming rolling resistance is similar from 15 - 30 mph). But the veloflex loses out. What gives the velo the special property that it gets worst at higher speeds, relative to the bonty, but the others do not. That is curious.
So, what does this graph tell us?
It says that a winged tire vs non-veloflex non-winged tires stay relatively consistent in drags of gram differential.
It says that a winged tire vs a veloflex tire wins (e.g. something unique to the veloflex makes it's drag rise much higher
as speed increases, unlike the other tires).
It says the veloflex Crr is about the same as the Bontrager.
It says - given that HED ran their tests with this tire with the H3 -- that if you aren't using a winged TT tire with that
wheel, you are going to lose BIG time watts... making an H3 + any other tire a pretty lousy choice.
And perhaps - one might think - that maybe if one smears some silicon in the groove between the tire/rim of a veloflex, one will get 5 1/2 W - if that is it's issue.
I am just so confused.
Dave Linenberg
http://reviews.roadbikereview.com/...worlds-fastest-tire/
The relevant information is:
Very interesting to see that at low windspeeds (15 mph), where Crr would be dominant - that the
bontrager tests so close to the veloflex record. (Care to comment on that Al? Tom?)
I find that interesting, to say the least.
I talked to HED, and they said that their aero charts for the H3 clincher were produced with the Bonty TT tire above. And that they observed about a 20 gram differential over the Mich 23. Bontrager seems to see more than double that from
the chart above.
I understand that a great tire can make a wheel great ... but it is hard for me to believe at 30 mph, there is a 50
gram differential (or about 5 1/2 watts) due mostly to the "wing" (I guess - or some mysterious Cd shape problem) over the veloflex - which starts out about the same.
And with regards to the other tires - all the other non-winged tires seem to maintain a consistent gap at higher speeds (???!!!)..which is strange, since you'd think the advantage of the wing would come into play. ( assuming rolling resistance is similar from 15 - 30 mph). But the veloflex loses out. What gives the velo the special property that it gets worst at higher speeds, relative to the bonty, but the others do not. That is curious.
So, what does this graph tell us?
It says that a winged tire vs non-veloflex non-winged tires stay relatively consistent in drags of gram differential.
It says that a winged tire vs a veloflex tire wins (e.g. something unique to the veloflex makes it's drag rise much higher
as speed increases, unlike the other tires).
It says the veloflex Crr is about the same as the Bontrager.
It says - given that HED ran their tests with this tire with the H3 -- that if you aren't using a winged TT tire with that
wheel, you are going to lose BIG time watts... making an H3 + any other tire a pretty lousy choice.
And perhaps - one might think - that maybe if one smears some silicon in the groove between the tire/rim of a veloflex, one will get 5 1/2 W - if that is it's issue.
I am just so confused.
Dave Linenberg
