Qulbix has just introduced a new Raptor model that is slimmer and lighter than their popular Q140, and if we were going to build up an off-road ebike right now, this is the frame we would use…and this article will explain why we like it so much.
Qulbix, a Company that is evolving
Back in 2014, we began seeing off-road hot rodders using a frame they bought from a company called Qulbix (pronounced Cool Bikes), and you can read our article about them here. Builders were buying the Raptor frame, and outfitting it with the components of their choice.
They were getting a lot of feedback from customers, and just a few months later, they introduced a new slimmer model they called the Raptor 140. The name means the central battery space was only 140mm wide (5.5-inches, roughly the width of a dollar bill). Even so, the actual battery space was larger than before, to allow a huge battery pack to be fitted in order to allow high volts, high amps, and long range.
Last year, there was a huge milestone that popped up in the ebike battery world. The major 18650-format cell manufacturers released quite a few new models of cells, some of which provided very high amps, and others which had much more range. We wrote about these amazing new cells here, and their existence has been a game-changer in the ebike world.
One of the reasons I have been such a vocal fan of the Qulbix company is because they have boldly made innovative improvements to their product line, and they have done this relatively quickly in response to feedback from their most passionate customers. The option of the new power-dense and energy-dense cells provided an opportunity that they did not hesitate to take advantage of.
The 18650 number means that these popular high-current cells (developed for the global cordless tool market) are 18mm in diameter, and 65mm long. So the question then became…how narrow (and light) could the battery compartment of the next-gen Raptor be? The answer is…the battery compartment has a 76mm inner width (a mere three inches!).
The Battery Compartment
Below is the official company engineering drawing to show the dimensions of the Q76R battery compartment, which has been optimised to hold 240 of the 18650 cells mounted on their sides. Those numbers may not seem impressive at first, and you might have thought you’d have to give up a lot of power and range to have a slimmer and lighter battery compartment, but…not here!
I know of one builder who is working on creating a 20S / 12P pack using the Panasonic-Sanyo “GA” cell, which is rated for 10A. Since he is designing this pack to use twelve of the 10A cells in parallel (12P), then it will be capable of 120A of current. The 20-cells in series configuration (20S) provides a nominal voltage of 74V. This means that 74V X 120A = 8880 watts of power (12 horse-power, but with full torque at only one RPM).
The average “nominal” voltage of a 20S pack is 74V, but if you follow our recommended charging protocol of 4.1V per cell max, a 20S configuration would be 82V when fully charged.
The GA cell has a nominal capacity of 3500-mAh per cell, and when bundled in 12 cells per Parallel group (12P), that pack would have a capacity of 42-Ah. And, to get the total power available, 74V X 42-Ah = 3108 watt-hours. For those who are new to this game…that’s a LOT! And the amazing part is how slender and fairly small that impressive battery pack will be, compared to the batteries from just one year ago.
Here’s our article on the five most popular rear hubmotors that enthusiasts have been using, to give you an idea what motors would be common for a frame like this.
350mm___Bottom bracket height
880mm___Minimum Bicycle seat height
860mm___Minimum Moto seat height
230mm___Rear Wheel Travel
200mm___Front suspension Travel (when using the recommended DNM USD8 fork)
150mm___Head Tube Length
44mm___Head Tube Inside Diameter (ID), suitable for semi-integrated 1-1/8 inch headset bearings (not included)
30.9mm___Seat Tube Inner Diameter (ID)
30.8mm___Seat Post OD
35mm___Seat Tube Outside Diameter (OD)
83mm___Bottom Bracket (BB) width, BSA/English thread 1-3/8
90mm___Maximum rear tire width the frame allows (3.50-inches, measured using a 26-inch tire)
40mm___Rear Shock Bushing Length
240mm__Eye to Eye shock Length
Recommended rear shock: DNM RCP2 240mm X 76mm, 9.5 X 3-inch, with 40mm bushings.
Alternative shock sizes verified to work well:
267 X 89
222 X 70
216 X 63
Stock rear brake caliper mounts compatible with 200mm and 203mm diameter discs.
Battery compartment interior width: 76mm wide
Battery compartment side opening: 230mm X 475mm
Frame material: a steel grade that is stronger than Cromo
Side Plate material: aluminum alloy
Frame weight: 7.4 kg in bicycle config (with no controller guard) 16.3 lbs
Frame weight: 8.2 kg in moto config (with no controller guard), 18.1 lbs
Drop outs type: 10mm slot, clamping style.
Drop out width: 155mm stock, 165mm on request
The majority of their business has been to simply sell the frame kit, and customers can often save on shipping costs by sourcing the wheels, fork, and motor from local businesses (or from a bike they already own). However, Qulbix will be happy to sell anyone a complete turn-key Q140, or a Q76R. Contact them on their website for details and current prices.
Here is a link to the Qulbix Facebook page
Here is a link to the endless-sphere forum discussion on the Q76R
Here is the Qulbix home web-catalog
Written by Ron/spinningmagnets, February 2016