At JWSHOP, we're not afraid of challenges. Our latest? Transforming a Sur-Ron Ultra Bee into a true motocross beast, capable of competing with the best, even dethroning the queen, the Stark Varg. After more than six months of intensive development, mechanical woes, and relentless testing on all terrains, we finally present the full report of this extraordinary preparation.
Hold on tight, we're taking you behind the scenes of a project that pushed us to our limits!
The Ambition of a "Stark Killer": Genesis of a Crazy Project
The initial idea was simple: what if we created an Ultra Bee so optimized that it could stand up to the formidable Stark Varg? A daring gamble, especially considering that the Ultra Bee, while full of qualities, is not initially designed for such intensive motocross use. But at Jowill, we like to push boundaries. So we ordered an Ultra Bee with the clear objective of preparing it for motocross, aiming for maximum possible performance.
This project spanned over six months, a period during which we faced many challenges. The Ultra Bee being a relatively new platform for this type of extreme preparation, many parts simply didn't exist. We had to innovate, adapt, and sometimes even custom-machine parts, such as the bushings to mount our White Power 85 SXS fork on the Xtrig triple clamps. We certainly didn't make it easy for ourselves!
Piece-by-Piece Preparation: A Goldsmith's Work (and Patience!)
To achieve our goal, each component was meticulously selected and tested. Here's an overview of the major modifications:
Aesthetics and Protections:
The first step was to give our machine a unique look. We opted for a dark grey glitter frame paint, protected by a PPF film. A custom decal kit from Riders Unik completed the look, applied only to the plastics to preserve the beauty of the frame. Carbon-effect Kydex protections were added, including a custom seat cover with carbon accents, available on our JWSHOP store.
Chassis: The Heart of Stability and Performance
This is where things got serious. For the front, the choice fell on a 21-inch KTM E-Freeride wheel fitted with a Geomax MX34F tire, combined with a White Power 85 SXS fork. A daring choice, as 85cc forks are not directly compatible. We had to machine specific bushings to mount them on Xtrig triple clamps. The cockpit was entrusted to a Renthal Fatbar Twinwall handlebar, Pro Grip carbon gel grips, and an 85 SX Formula front brake.
At the rear, the 19-inch wheel is also equipped with a Geomax MX34, and the damping is provided by the incredible EXT REA MX, with a specific EXT motocross preparation. For ground connection, Tarazone linkage and swingarm, more robust than the original, were installed.
Motorization and Battery: The Quest for Torque and Power
Initially, we had an EBMX 80V 73Ah battery coupled with an X9000 combo. While the power was there, the lack of torque and the difficulty in finding the right settings frustrated us. This EBMX motor, although powerful, did not offer the progressive feel desired for motocross.
The revolution came with the switch to the Torp TC1000 controller and the TM50 motor, powered by an Amperion 76V 76Ah battery (currently under development). With this setup, we reached 30 kW with incredible torque and finally achieved the desired progressive feel. The difference is striking, and this is what truly transformed the bike.
First Tests: Between Cold Shower and Revelation
The first laps at the Lyon Show were... an experience. On a very technical indoor SX track, with the still imperfect EBMX combo and suspensions not yet broken in, the feeling was not optimal. The lack of torque was the main complaint.
Subsequent tests on tracks like Rixheim confirmed these initial mixed impressions. Without the right engine feel and with suspensions still breaking in, the Ultra Bee struggled to fully convince us for pure motocross use, especially in direct comparison with the bewildering ease of the Stark Varg.
It was at Sainte-Croix, and especially after switching to the Torp combo, that the bike finally revealed its potential. More torque, better power management, and suspensions that began to work in concert. We were finally able to exploit the machine!
Ultra Bee in Motocross: The Final Verdict
So, is this Ultra Bee a good motocross bike? The answer is nuanced.
With the ultimate preparation we carried out, including the Torp combo and EXT/WP suspensions, it becomes a formidable machine, capable of absorbing big jumps and offering top-tier performance. It is no longer light-years away from a Stark Varg in terms of usable power.
However, its shorter wheelbase and steeper rake make it a little less stable at very high speeds or on very bumpy terrain compared to a pure motocross bike. It lacks some of the "royal" stability of a Stark. Where it excels is on more technical and winding terrains, where its maneuverability works wonders. It's a Light Bee on steroids, capable of tackling much larger obstacles.
If we were to do another motocross preparation, we might opt for a 125cc fork to gain even more absorption and stability, slightly modifying the rake to lengthen the bike a bit.
The Final Word: A Versatile Machine with Enormous Potential
This project taught us a lot. The Ultra Bee, once properly prepared, is an incredibly versatile bike. While our current version is motocross-oriented, it's worth remembering that a road-legal version, with adapted suspension settings, would be an excellent enduro machine, much easier to handle in technical sections than a Stark Varg, and still transportable on a bike rack!
We may have aimed a bit high with the "Stark Killer" objective for an unregistered bike, shooting ourselves in the foot regarding enduro versatility. But the result is a unique, high-performance machine that offered us incredible sensations.
And this is just the beginning! Our next Ultra Bee will be dedicated to enduro, with a different approach to maximize its qualities in this discipline. Stay tuned!
Find all spare parts and accessories for your Sur-Ron Ultra Bee on jowillshop.com. Do not hesitate to contact us for your preparation projects!