I have this here cycling jersey that I do not want to sew on.
That would cover the reflective Dainese logo. Since, with the years, I have learned to appreciate those Dainese products, I have decided that for that jersey I had to insist harder with developing a replacing version of the Aero Hump Pocket.
After some try and error, I have identified a solution that kind of works. I connect an Aero Hump Pocket on the jersey via those SportSoSKin pads (https://plus.google.com/117353072060865277873/) . They pinch together the jersey spandex and the Aero Hump Pocket one.
Here some pictures of what I have got.
This solution works. It can be put on in a few minutes without major problems. All other solutions that I have tested (safety pins, velcro) didn't really work. This solution can not be marketed but it could by developing on purpose some large snap on buttons similar to what the sportsoskin do.
This is more a Micro Aero Backpack, rather than an Aero Hump Pocket. Aerodynamically I have kind of the feeling that it is a little slower then the sewn on pocket. Probably 0.3 kmh. I have not measured anything so far. Just a feeling.
OK, I have never had rotation problems on the Roadtopistas mounted by me. I have always made sure to snug those screws to the max torque. However, when I have designed it did decide to allow to bolt in an M6 side screw that would have reduced to 0 the potential rotation problems. I have decided to test out the side screw setup on the last bike that I have built. This is the final result: needless to say that I had no rotation problems.
From the Japanese Magazine "Motorcyclist" December 1993, Page 286:
It does say that one of the new things in 1993 has been the appearence of leathers with an hump (Kobu Tsugi Tsunagi!). It explains that the purpose is top speed aero improvement. It says that the riders that used it were not saying much, but that a sure positive impact was expected.
I have yet to understand which is the real top speed impact of the aero hump at 300km/h, however, considering that the top speed variation from one lap to another is about 10km/h, for the same rider in the same day, the improvement should be below 3km/h, therefore it would have required many laps to accumulate evidence of the advantage. And indeed it took many laps (about 3 years) for the motorcycle community to adopt that solution.
Aero Hump Pocket , I have finished the development. It works perfectly.
I have been wondering where the pros were carrying the rain coat. After some tv watching it became clear that the pros were giving the rain coat back to the assistance cars. The spring 2013 has been extremely cold and rainy in all of Europe and in all the bike rides that I did I had the problem of carrying the rain coat. So after some thinking, knowing that (motor)bike riders gain about 10kmh thanks to the aero hump, I have decided to migrate the aero hump from (motor) bikes to (push) bikes. The result is that it carries the rain coat well but it can carry a water bottle also. Aero drag wise is worth 10Watts at 30kmh (it is an estimation. We had not yet a chance to power meter it scientifically). Therefore at 30kmh you gain about 1kmh. Absolutely in line with what a time trial helmet provides.
I am curious to see if it will sell.
Otherwise, all in all, since it has been used on bikes before (the motor) it is not my invention. The legend wants that it has been Mr Loris Reggiani together with Mr Jan Witteveen that invented it back in the year 1994.
I took part to a quarter mile race that we did with a bunch of buddies downtown Turin this summer. I had one of mine Road2Pista conversions. When there I gladly found out that there was an other guy with the same conversion.