JeffWills said:You should ask this question of the recumbent trike builders. There
are
Quoted message said:a few scattered over the world, and many of them sell parts to people
who are building their own trikes. Here's a couple manufacturers:
http://www.steintrikes.com/
Furthermore, soon there will be even more specialized one-side mount
hubs available on the market for home-builders and interested
manufacturers. The first set of prototypes are currently on the customs
check, but once they get here, we'll post a few images and information
about them.
What is so interesting about these new hubs? Well, the common disc
brake hub is designed for 26" rims, coming in approximately 55mm width
(center to center of the flanges) and around 58-60mm diameter of the
spoke holes. This results in around 12-13 degree angle between the L &
R side spokes and that works fine on the 26" wheel. However, on a
smaller rim, say 349ISO rims, the tension on the spokesis much greater
than on the large wheel, the spokes must bend much more and when
tightening the nipple, the section of the spoke where the thread starts
is already loaded in a wrong fashion, it gets bent, especially if the
rim comes with eyelets that tend to keep the direction of the spoke
closer to the above mentioned 12-13 degree angle. This reduces the
lifetime of the average spoke on a wheel with a big hub and small rim.
I took the time to investigate this detail further and have designed a
hub that is narrower beween the flanges by some 20mm (also reduced the
overall width) which should result with several minor benefits for use
on small rims. One of them is the better, that is, correct angle of the
spokes laced into a small rim, less weight, better aerodynamics of the
wheel (not much, but the effect should exist) and that will also allow
use of shorter axles, less weight, less kingpin inclination to achieve
center point steering, and with that less distortion in steering
designs when the wheel is not in straight ahead direction. Some might
not know that steep kingpin inclinations result with raising/lowering
the steering rod ends during turns. That results with more or less
unpredictable steering design layouts, and if someone designs a
steering layout that looks perfect on paper, it all might be ruined by
distortions that come from the vertical movement of the rod end on the
steering rods.
There is so much more to tell about steering designs, but that gets way
off the topic...
Cheers,
Robert Stein
