Wednesday, January 2, 2013

Finally -- Speed Comparison Between Two and Three-Wheeled Handcycle

My inclination that a two-wheeled handcycle is faster than a three-wheeled handcycle may have some ammunition.  The site -- http://www.kreuzotter.de/deutsch/speed.htm -- allows one to compare the aerodynamic efficiency of various bikes and riders in many configurations. The bike types include a three-wheeled handcycle.  (BTW, this is only available on the German edition and not the English one-- but math is math no matter the language.)

One edition of the calculator mentions the use of SRM's PowerMeter for verification of the aerodynamic efficiency results.

The difference between a two-wheeled low-rider recumbent and a three-wheeled handcyle is actually greater than I envisioned.  If indeed the two-wheeled handcycle works, I may be looking at  a 5 mph improvement under race (and perfect) conditions.

As I had mentioned in an earlier post, I thought I was pushing out about 200 watts average (hey, I am old and it is only arms!) over about 20+ miles at near race pace.  The calculator output below pretty much confirms that. Considering that I had actually raced 26.2 miles at 19.1 mph with no drafting, a large hill and about 40 turns/curves -- many of which required braking -- I would expect that the the calculator -- with the 3-wheeled handcycle bike type selected --would predict a slightly faster pace since the calculator is using 0 slope. It did indeed (about 0.7 mph faster @ 19.8 mph):


The calculator with a 2-wheeled recumbent low-racer (all else equal) calculates 24.3 mph:

There you have it!  A 8.3 kph difference in bike types equates to as 5 mph increase in speed at race pace.  For my longer workouts (90 - 120 miles) I can expect  (well, "hope for") a 4.2 mph improvement.  Of course this is under perfect conditions that never exist!





1 comment:

  1. bare with me where do you get the foam to make the mold all i got is the pink panther stuff from homes lee .

    ReplyDelete