Grin Tech GMAC upgrade kit for the Juiced Crosscurrent, S, X

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  • Image 1
  • GMAC motor with torque arm
  • Quality rim
  • Sapim spokes
  • Baserunner controller
  • CA3 aux pot al
  • CA3 bracket
  • MF switch
  • Cycleanalyst V3-WP
  • Torque sensor cable
  • throttle cable
  • brake cable
  • light cable
  • battery cable
  • Image 15
  • Stainless steel Torque arm adapter

Product Reviews

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  1. Incredible ride for the price

    Posted by Jacques B├ędard on 2023 Feb 18th

    At the end of 2021, I purchased a Phaserunner bike. Shortly after that, I acquired the Gmac upgrade for the Juiced Crosscurrent bike. At the time, it was an illogical decision to upgrade the Crosscurrent knowing that I could not recover the cost by selling it afterwards. It turned out, money is not always a good guide. Since I broke my Phaserunner in midsummer, I ended up using the Juiced for half of the summer of 2022. Because of that, I am in very good position to compare both bikes.

    Both the Phaserunner and the modified Crosscurrent exhibit quite a similar ride. The Crosscurrent feels slightly more agile owing to its narrower tires (1.75") compared to that of the Phaserunner (2.4"). The phaserunner is also a bit heavier, not that it matters at all when you are riding. I noted some riding differences between the two bikes caused by the torque sensors. The Phaserunner senses torque on the crankset while the Juided does it on the derailleur. Technically, the Juiced torque measurement varies with the gearing on the derailleur which really is a measure of the torque applied to the rear wheel. Both configurations give you a nice ride. I am having difficulties telling you which one I like better.

    If you have a Crosscurrent and you are wondering whether it is worthed paying for the upgrade, I would tell you to just go ahead. Your Crosscurrent already lost value and what you will be getting could not be purchased under 5000$ anyway. For the cost of the upgrade, you will be getting rid of the Bafang motor noise/vibrations in addition to having an electric bike that gives you full power at each assistance level. I must also add that the Grin controller is completely configurable.
    I changed the handle bar for a raiser bar which provided a raise of 90 mm. This makes the bike more comfortable without being completely upright. After going through a number of saddles, I finally settle for a wide Btwin sold at Decathlon.
    I convinced my brother to upgrade his Crosscurrent. Before he made the change, he was riding with two 1000-kWh batteries doing rides of more than 150 km. When he started using the upgrade, he felt that this was really how electric bikes should be designed. I do agree with him.
    Take a look at the bike.

Product Videos

Regen Braking and Electric Bicycles, Justin's Presentation from 2022 BC Bike Show 46:52

On March 5th 2022, Justin gave a talk at the BC bike show about regenerative braking as it pertains to the world of electric bicycles. Regen is an important topic that's been largely misrepresented by the ebike industry due to the focus on mid-drive and freewheeling hub motors, so we wanted to set the record straight on many areas. This follows some of our original research on regen which we posted on this Endless-Sphere thread many years ago: 0:00- Intro 0:33 - What is Regen? 1:53 - Electrical Principles 4:40 - Problem with Freewheels 7:15 - Negative Marketing 8:11 - Is it Worth It? 10:04 - Motor Drag 12:27 - % Recaptured 16:10 - Saved Brake Wear 17:45 - Cost Savings 20:04 - Regen Motors 23:00 - Activating Regen 26:00 - Variable Regen Brakes 27:40 - Alternative Regen Controls 30:29 - Backpedal Regen 35:22 - Speed limit regen 37:45 - Regen Efficiency 38:20 - Comparison with Mid-Drive 40:18 - Motor Heating 40:45 - Axle Wiggle 42:05 - The Future 42:45 - Q&A

  • Regen Braking ...
    On March 5th 2022, Justin gave a talk at the BC bike show abou...
Grin Tech

Product Description


Do you own a Juiced CrossCurrent, S, or X? 


Note that if you own a CCX, there are two issues that we have run into.  There is not enough clearance between the seat tube and the tire to mount the controller as we have on the CCS. It may have to be mounted facing sideways on the seat tube.  Also, the kickstand mount could be too far away for the torque arm to attach properly, so we are including a laser cut stainless steel extender bar that will solve this in most cases.

This plug and play kit that will make the CC/CCS/CCX a much more powerful and capable bike. It will be smother with less noise from the motor as well. It starts with the Grin GMAC geared clutchless motor, and adds the Grin CycleAnalyst V3 display, and Baserunner controller.  All the necessary wiring and programming is included, just bolt it on and go.  


Information on the GMAC motor:


  • Peak power is increased from 750W to 1500W.
  • Peak torque is increased from about 50 to about 90nm.
  • You gain variable regen braking, saving brake pads and energy.
  • The system is highly tunable, and gives you loads of info to geek out on.
  • For advanced users you have the ability to tune the torque sensing for sensitivity, gain, timing.
  • Motor temperature feedback means you can't overheat the motor.
  • Easily dial in an overall power limit to extend your range.
  • Legal and off road modes can be switched with two key strokes.
  • Our custom torque arm bolts to the kickstand mount, giving you a clean install.
  • You get the second-to-none Grin Tech quality and warranty.
  • This kit requires a minimum 12.8 battery, best to have the 19.2 or 21ah 48 or 52V.
  • Predicted speed capability is 43 kph on 48V and 45 kph on 52V.  Climbing a 10% grade predicted speed is 32-35 kph.
  • We will be offering a new 48V 16ah high current 21700 battery sometime in 2022.

Parts included in this kit:

  • GRIN 10T GMAC clutchless geared motor
  • Weinmann ZAC19 eyeleted 700C rim
  • Sapim 13-14 ga butted spokes black
  • Custom GRIN torque arm to fit Juiced CrossCurrent/S/X
  • GRIN Torque plate
  • GRIN Wheel building labour (The motor comes hand assembled into a quality rim)
  • GRIN Baserunner L10 controller
  • GRIN Baserunner Tube mount
  • GRIN CycleAnalyst V3 CA3-WP with MF switch
  • GRIN CA bracket
  • GRIN CA3 AUX AL adjustment dial
  • Custom cable set for brakes, throttle, torque sensor, 12ga battery to controller wire, new 12ga battery connector, Y cord to power up front light with tap for optional rear light. (note that you will no longer have a switch for the light on the display. We are working on a plug and play handlebar switch solution, or you could upgrade to the SPL-01 light that comes with a switch.)
  • Stainless steel torque arm adapter.
  • Black cable ties.

Tools that you will need to install this kit:

  • Metric socket set
  • Metric wrench set
  • Metric Allen wrench set including a 1.5mm to remove the Juiced display
  • Torx key set
  • Philips #1 shorty screwdriver
  • Side cutters
  • Chain whip such as the park tool SR-12.2
  • Cassette removal tool with a hollow middle such as the Park Tool FR-5.2
  • Heat gun or lighter for shrink tubing
  • Tube of dielectric grease (available at your local auto parts store)

 Detailed installation instructions are here: