The "+Flat 90" wheelset is a proven and thermally resilient wheelset for drum braked trikes and velomobiles.
Sturmey Archer drum brake hubs are used in the 90 mm version with round heat sinks. The wheelset is almost identical to the +Silver 90. In contrast to this, however, the outer contour of the flange is turned off. This means that this wheelset can be covered with carbon wheel covers, so that it fits perfectly with velomobiles with wheel arches that open to the sides.
These +hubs are significantly more resilient and can dissipate more braking heat than the uncooled hubs. This represents a major safety gain when driving uphill compared to the original hubs. Together with silver round spokes Laser and brass nipples from Sapim, these become our tried and tested Ginkgo velomobile wheels.
By using Polyax nipples in conjunction with special nipple washers, the spokes can run more diagonally into the rim. This is necessary when using hubs with large bolt circle diameters.
The spoke tension in our velomobile wheels is chosen to be very high. This is necessary to counteract the expansion of the drum under heavy thermal loads due to braking maneuvers. The very thin laser spokes absorb part of the voltage drop due to their elasticity in the thinner middle section. This and the spoke tension being as uniform and high as possible ensures that the wheels have a high mileage.
To select the right rims, select the appropriate rim and the number of spokes for the variants.
Most rims are tubeless rims. There is a security reason for this. If there is a sudden loss of air, the tire bead gets stuck behind the tubeless hump of the rim. This means that the tire cannot jump off the rim so quickly, safe rolling is guaranteed and the rim is protected by the tire.
Of course, our wheelsets can be supplied for use with 12mm and 15mm axles.
The default is 12mm. When used in A7, W9, M9, A9 and other vehicles with 15mm axles, this can simply be specified when ordering.
All wheelsets are built ready to ride. The wheels are pressed and the spokes are stretched. Nothing needs to be re-centered or re-tensioned here.
Of course, a suitable, high-quality rim tape is already installed upon delivery. We always use tubeless straps twice to ensure the highest possible safety.
In addition, a wheel report is included in which the key data of the wheelset such as concentricity, materials used and spoke tensions are recorded. This data is also stored in our company database so that we can quickly provide the appropriate replacement in the event of damage. To identify the wheels, a 4-6 digit serial number is engraved in the rim well near the valve hole.
If you have any questions when selecting a suitable wheelset, we are happy to advise you by email or telephone.
used material:
Hubs: XL-SD drum brake hubs with 10 round heat sinks each and a machined outer contour
Spokes: Sapim Laser silver
Nipples: silver Sapim Polyax brass nipples
If necessary, washers to improve the nipple inclination
Rim tape