Quote:
Originally Posted by Grant-53
The Trek shape can be applied to a full body fairing like that of wphamilton but with a nose piece. My cone and waste basket fairing pictured in the bike pic thread improved my easy cruise speed from 10 mph to 15 mph. The fairing should cover from the shoulder to just above the knee. This will cost less than a recumbant and be just as slick. Make sure your brakes are in top condition. See also the recumbent.com forum thread on building an upright racer. The pictures of upright Mike and upright David.
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That is very interesting result, even simple fairing seem to be great help
As it was calm day/morning, I did test bit of aerodynamics. I don't know if my results are really true and solid, but I did measure speed and time with GPS and put data to proven formula.
Cd of 1.492 is what program did claim.
I did tape measure myself and bike, estimated frontal area to be around 0.966m^2, that gives CdA of 1.441272.
Awful lot higher than earlier linked under CdA of 0.8.
CRR of 0.004, maybe possible, tires are not very special ones, 37mm and 32mm.
Front MITROC 28" Ur 32-622 m/v M-201
Rear Nokian Rollspeed 37-622 28"
Thead of those is rather smooth with center narrow smoother area, they do roll really well from my opinion.
Graph from coast down test:
This is fastest that I can do that 4km distance, coming back is always easy, but to go that fast I had to cycle so fast that I could literally taste blood in my mouth, so if I manage to do that trip any faster there has to be improvement in somewhere, this should be then baseline. At the end there is coast down test too.
When I get new handlebars I do another test, will be interesting to see if there is much change. Hopefully weather would be close to same so I could use same clothing too.
I did use Tomtom sat nav and tripmaster software running on it, to gather log, attached navigator to handle bars with metal wire, crude, but efficient.
Altitude data from Tomtom is bit inaccurate most of the time, but compared to phone + Maveric, I get 1Hz resolution and also speed logged, which Maveric does not log.