Assuming I average 21-22 mph on a road bike with box rims and I switched to HED 3 clinchers on the same bike, how much faster would I go? Assume all other factors are equal, and we’re talking about a relatively flat course.
Just curious. Thanks.
Assuming I average 21-22 mph on a road bike with box rims and I switched to HED 3 clinchers on the same bike, how much faster would I go? Assume all other factors are equal, and we’re talking about a relatively flat course.
Just curious. Thanks.
Assuming the tires and tubes are the same, then it all depends on the wind angle, with higher crosswinds giving the H3s a bigger bonus. According to the Hed website, an H3 has an advantage over a 28 spoke low profile rim of 30 to 130 gm of drag (when tested at 30 mph) over a range of 0 to 20 degrees of yaw. Since you have 2 wheels, but the rear is slightly sheltered (~40%), we’ll use a factor of 1.6 times those drag values, or approximately 50 to 210 gm for both wheels. This corresponds to 0.1 to 0.46 lbs of drag. The “rule of thumb” is that 0.1 lbs of drag (30 mph drag, that is) is ~equivalent to a time difference (at the speeds you assume) of 0.5 seconds per kilometer.
So, in this case, we’re talking about a time difference of ~0.5 to 2 seconds per kilometer, depending on the wind direction and strength.
Hope that helps.
Wow. That’s really depressing. I think I can stand and sprint a little harder and save the $1500.
I’ll summarize:
Box rims/spokes to Hed 3’s
saves 1-2 mins per 40K depending upon your speed and wind (the slower you are the MORE time savings)
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But then consider the time you save in the run by not punishing your heart and legs for 1 minute less time =)
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I feel too stupid to ask this question in it’s own thread, so sorry for the slight hijack.
Would there be much of an advantage to adding a disc wheel to a road setup?
Sure, same advantage - actually more since it is not as shielded from an apparent tight tuck aero frame. But, discs aren’t legal for most road races so …
Let us not all forget that rider positioning is 80% of your drag! Up to 3 lbs of drag reduction (a huge amount BTW) can be saved by an excellent position vs. a poor one. Wheels, frame, etc. can barely get you 1 watt (gross generalization)
I feel too stupid to ask this question in it’s own thread, so sorry for the slight hijack.
Would there be much of an advantage to adding a disc wheel to a road setup?
No problem on the hijack. Interested myself.
Thanks for all the other responses too.
Where in NJ are you? I can let you try a pair of Blackwell 100’s or a Blackwell 50/100 combination.
Where in NJ are you? I can let you try a pair of Blackwell 100’s or a Blackwell 50/100 combination.
Thanks. PM on the way.
The advantage of a disc wheel would be offseted by the negative comments of the roadies for using a disc wheel on a road bike.
Road bikes are also used for climbing and their would be not advantage of using a disc wheel in a major climb.
“discs aren’t legal for most road races so …”
since when?
Not that you’d use a disc in a road race anyway.