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Electric Cargo Bikes


Option 1: Kombi 2000 with GMAC 

The Kombi 2000 (with GMAC motor) is our premium electrified version of the Yuba Kombi. With the Kombi, you start with an adventure-ready and heavy-duty cargo bike frame with dual disc brakes. Its stout rack system and host of accessories including waterproof bags mean you can adapt it to your hauling needs. We are ready to guide you through picking Yuba accessories and non-Yuba accessories (pump, lock, lights) to help you set up your system, with our 75+ combined years of cargo biking experience. 


Our electric platform consists of a 52V in-frame aluminum-cased lithium-ion battery comprised of Samsung cells. The aluminum battery case doesn’t take up prime cargo space, is centrally located for a good center of gravity, and acts as heat dissipation for the thin controller. The battery system is scalable. The max capacity of the aluminum case is 1.5 kWh. Standard option is 1 kWh with room for expansion to 1.5. 

Range expectation. Steep hills and heavy loads will make every bit of difference. For the 1 kWh battery, expect a 25-50 mile range. 


The motor is the Grin Cyclery GMAC ‘fast winding’ which offers excellent acceleration and is capable of approximately 32-35mph on flat ground. This geared hub motor is relatively quiet and lightweight as motor systems go and still offers powerful regenerative braking. With regenerative braking you can put about 10-12% back into your battery, and you’ll also save brake pads! 


We have tested this motor with steep hills and heavy loads, and also light loads for top speed. While the overall weight is less than 70 lbs, the bike can tow or haul 300 pounds. 


Starting pricing is as follows: 

Base bike: Yuba Kombi with larger front chainring, $1350

Grin GMAC motor system: including Cycle Analyst 3 display, throttle, Base Runner controller, $1100

Build fee: $500

1 kWh Battery and charger:$1300


Base price $4,250 + sales tax on everything but the build fee. 


Upgrade options:

Yuba Baguette waterproof bag: $150

Upgraded 1.5kWh battery: + $525

Upgraded premium charger: Cycle Satiator charger offering battery saving percentage charging: + $300 

Simple upgraded charger with % charging: Offers 80% and 90% charging but has no screen. + $150 


Option 2: Kombi 750 with Bafang 750 mid-drive

Also lightweight, with a less expensive mid-drive motor. Very reliable: most popular ebike motor on the planet. Sold with 1kWH battery for a base price of $3250. Lower top speed (~30 MPH) , excellent hill climbing power at 10-15 MPH More info and photos coming on Kombi 750. 

Starting pricing is as follows: 

Base bike: Yuba Kombi, $1200

Bafang 750W motor system: Bafang 750W lightweight mid-drive motor, color handlebar display, brake-sensor brake lever, gear sensor, $800

Build fee: $500

1 kWh Battery and charger:$1250


Base price $3750 + sales tax on everything but the build fee. 



Smart charger: $175 . This charger has modes for 80%, 90%, and 100% . Charging to 80% when you only need to go a short distance is a great way to extend the life of your battery. This is commonly done in the world of electric cars for the same reason.


Kit Install Service:


If you bring a bike that’s a suitable candidate for an electric bike, here are the options. 


Motor choice: 


  • GMAC – more like a motorcycle because it has a higher top speed and a twist throttle. Source: Grin Cyclery. GMAC motors also offers regenerative braking, which is both effective at slowing you down, fun from a gee whiz and environmental perspective, and better for the life of your disc brakes.   
  • Bafang 750 . Mid drive motor with modes. Still very powerful, possible better at climbing steep hills. You change speeds by going up or down on with your mode buttons. Bafang systems do not have a twist throttle but they do have a ‘Nitro Boost’ thumb button, which is useful for getting through yellow light. We call it Nitro Boost, because it delivers 120% of full power. You can use it continuously (at the expense of battery life). The most effective use of the Nitro Boost is to allow you to be in a lower mode like 1 or 2, but have access to full power when you need it. Once you are in mode 4 or 5 the Nitro doesn’t do as much, relatively speaking. We do not recommend using the Nitro from a dead stop. It puts a lot of strain on the chain. 


Battery choice: 


Both GMAC and Bafang 750 systems can use 48 or 52V batteries. You can also ‘overclock’ your system for a higher top speed, with a 72V battery. This is fine on a GMAC motor but risky on a Bafang 750. On a Bafang 750, using a 48 or 52V battery gives a lot of peace of mind because millions of others are using the same voltage and you know you won’t be overheating your motor. 


Battery form factor will depend on your bicycle frame. The most common battery type is the ‘Shark’ style, which mounts where a water bottle normally goes (and uses the same screw holes). Because it’s the most common, it is also a good value (mass produced). But keep in mind that this style battery will have an upper limit of approximately 0.7 kWh capacity, which may be too small for your needs. 


Both GMAC and Bafang 750 seem to have similar range. Terrain and how you ride has everything to do with how long you actually get from your system. Hills = smaller range. Riding full throttle or Mode 5 = smaller range. Flats = long rang. Going slower = long range. Between GMAC and Bafang 750, one does not seem radically more efficient than the other. 


If your frame is compatible with the largest ‘shark’ style battery packs (0.7 kWh) you can expect a range of 25-30 miles on flats with occasional hills. For heavier cargo bike use on hillier terrain we generally recommend 1 kWh.


As a useful data point,  I was able to go 13 miles with a medium light load over very hilly terrain in Nevada County with a 0.5 kWh battery recently. 


Custom battery installs: 




  • Motor install fee $500. This is an estimate and can go up if major custom work is required to complete your build. All ebike installs are finicky and require some filing and fiddling. Major custom work would mean fabricating a completely new bracket to deal with a fit issue with your bike. We are generally able to hit the $500 build fee without increasing it. We will certainly try to flag all potential issues during the initial walkaround of your bike.  
  • Parts other than batteries: 
    • If you buy and bring us all the parts, and no ordering is required, we’ll charge only the build fee.
    • If you require us to tell you what to buy in order to bring us parts, we’ll charge at $100-200 consult / system design fee. 
    • If you bring us most of the parts but some additional purchasing is needed to get through the build, we’ll charge accordingly and try to let you know as much as possible ahead of time. 
    • If you want us to be a complete one stop shop, we will either charge regular retail prices listed on for GRIN products such as the GMAC motor or 1.4X the retail prices of Luna Cycle on Bafang systems. The reason is that we are GRIN dealers and are listed on their official dealer page, while LUNA Cycle doesn’t offer dealership, but has the best prices on Bafang systems. 
  • Battery pricing: 
    • We sell batteries! Some bikes benefit from custom battery installs because it allows better range and perhaps lower center of gravity. Or perhaps the bike doesn’t have a place for a battery. On the folding bike above there was no other option.  If so we will price as follows: 
      • $1 per Watt Hour + custom case price of $300-500. Custom cases are shown in the photos.