Rotwild Gravity Prototype
The latest engineering highlight from the makers of ROTWILD: As one of the first manufacturers, German premium brand ROTWILD present a new gravity prototype with mit 27.5” wheels. Born from the development collaboration with freeride legend Richie Schley comes the first true blue downhiller by ROTWILD with 200 mm travel, 27.5” wheels and an extremely low weight of approximately 15.5 kg (without pedals).
The focus point of this bike is the all-new hydroformed frame. Geometry and chassis were tuned to meet the personal wants and needs of the Canadian freeride professional. The precise engineering of all relevant aspects ultimately leads to outstanding ride characteristics: Compared with 26” downhill shredders, the new gravity prototype leaves nothing to be desired in terms of handling and agility, while at the same time making the most of the advantages the larger wheel size have to offer.
Last weekend, pro rider Richie Schley took his new gravity bike out for some rigorous testing on the many freeride tracks in Saalbach-Hinterglemm and was delighted by his findings:
“My first impression of the new 27.5 DH bike was very positive. The bike was very stable, yet I could still throw it around like any other DH bike I have had in the past. I think the bigger wheels provide better traction, so it seems to translate to going faster. The low bottom bracket height makes for awesome cornering.“
Frame concept
The ROTWILD engineers designed the head tube with extra volume and stability specifically for long-travel dual crown forks. Therefore, it does not require additional welded gussets. Every added weld puts a strain on the material, therefore by applying intelligent shaping design and relinquishing unnecessary gussets, ROTWILD achieve greater stability.
In order to be able to accommodate 200 mm of travel in this compact frame, the shape of the bottom bracket area was completely revised, providing ample space for shocks with piggy-backs. At the same time, the bottom bracket was lowered to 350 mm. The same measures were applied to the low stand-over granting more leg room.
Another advantage comes with the 27.5“ wheels: The hubs are distinctly higher than the bottom bracket, which translates to improved ride stability.
For great agility, the rear end is 440 mm short, which makes it comparable with that of 26“ gravity bikes. The desired ride balance is achieved through the perfect combination of short rear end, slack steering angle and the 27.5“ wheels.
The slack steering angle of 63.5° provides outstanding stability. The 420 mm reach and 597 mm stack guarantee perfect control in various riding situations.
Further details
The frame is compatible with dropper seat posts with internal cable actuation.
The newly designed main pivot bearing is reinforced by a one-piece yoke. Additionally, the bearing on the right hand side was enlarged.
Axle width rear: 157×12 mm for more stability.
With its wider chain line the BB83 bottom bracket enables short chain stays and great tyre clearance at the same time.
ISCG-05 adapter.
Weight without pedals: approx. 15.5 kg.
Status: Prototype. Series production planned for 2015.
Setup: tbd.
Images show Schley’s personal bike with X-Fusion suspension, Shimano drive components as well as DH prototype wheels specifically developed for this bike by Crankbrothers.
Click on the image below to watch the intro vid.