Reluctantly, because I’m losing business to do so, LiveWire is taking the position that the Schlumpf hub is too narrow for a 36" wheel. It would result in a wheel with improper geometry. Although the Airfoil rim would provide a lot of stiffness, the resulting wheel would not be properly built, and excessively flexy and weak. It’s even marginal for a 29er wheel. A wheel built with this geometry, with whatever skill, will tend to rub on brake pads and frames in general use.
By comparison, a Suzue (61mm), Profile (62mm), KH 2005 (67mm), or even Harper hub (60.3mm) are 60mm+. A rear track hub for a bicycle is on the order of 63mm (Suzue Promax) - 80mm (Phil Wood).
It’s my opinion that 100mm flange-to-flange, like the widened Suzue (101mm) first pioneered by Chris Reeder and subsequently produced by GB4, then by Tom Miller, or the UDC Coker hub (100 mm), is the appropriate width for a 36" wheel for general use. I imagine that I would also share Pete Perron’s position that 80mm is acceptable as well for general use (hard hill climbs, use of brakes, etc), though I really do think that 100mm is more suitable. In Pete’s 2nd generation case, his brake is a centrally-located disk brake, which eliminates the issue of brake rub, and leaves only the issues of frame rub (much less restrictive) and overall strength (plenty for road use of a geared unicycle).
If I remember correctly, the stock Coker hub was on the order of 50mm, and the excellent QU-AX hub is at 55mm, both unacceptable.
This opinion is not the result of lack of experience with larger wheels, but based on such, and based on the year-long project that resulted in the prototype Strongest Wheel, still going, er, strong. In that project, I found that, even when using a wider hub and Airfoil rim, the rim would rub on the brake pads. Not till I raised the tension to the highest appropriate for the rim and geometry did that problem go away.
To have a good wheel, it’s not enough to have a properly trued, uniformly tensioned and highly tensioned wheel based on good components. It’s important to have good geometry as well.
As a result, I’m restricting my own builds with the current Schlumpf hub to 29ers and below, and feel that the hub is most suited for 26" and below, given the present flange width. I know that there exist 36’s with this exciting new hub, and that people are enjoying them. I just have to draw the line somewhere.
Similarly, if someone, looking to use the wheel off-road, ordered a 36" wheel with a Profile hub, which I support wholeheartedly, I would build it with caveats, but would try to steer him or her towards a KH, which is wider. A wider Profile or KH would be ideal, but in the quantities required to get a special order, impossible for LiveWire at the present, not to mention technical restrictions on axle length and the like. I would not want to use a Suzue (little justification when the wider hubs are available) or a Qu-ax (too narrow).
There might be special circumstances that dictate exceptions, such as for track use only where wheel strength is less important and brakes are not a consideration.
I know that this position is not universally shared, and I apologize for any inconvenience that my holding it causes. I look forward to the next evolution of the promising Schumpf product to see how it develops.
In the meantime, there are lots of cool projects in the works and to come. Working with Scott Wallis is a real pleasure and there’s lots of fine riding to do, with great people, here in Texas.
Thanks, Greg, for your words, so pleasing to the eye to read.
. Check out the specs including the spoking pattern on the Equipment page of the Laos Unitour website: