At first glance, Sunrise Medical’s new Empulse M90 wheels look like any other power-assist wheels. They have a hub motor with an integrated battery pack that adds power to a manual wheelchair by simply swapping out the wheels. 

The difference between the M90s and other power assist wheels is that the M90s operate somewhere between power assist wheels and a full power conversion akin to the recently released Power-Flex or Spinergy’s discontinued ZX-1. The M90s come with a wireless joystick that you can use to control both the speed and direction of your wheelchair. The joystick mounts to your frame so it sits in a standard controller position, and it has a quick release so you can quickly detach it for transfers or transport.  

The selling point for manual to power chair conversions is that they give you the option to enjoy the fitness and functional benefits that manual chairs provide, while having the option to go full power when you need to cover long distances, access terrain that you wouldn’t be able to under your own power or rest your shoulders from injury or exhaustion.  

The M90s take that concept further.  With the M90s, as opposed to other power chair conversions, you still have your rear wheels attached. You have two drive modes: “All-Way Toggle” and “Speed Controller with Handrim Steering.” In All-Way Toggle, you control your chair via the joystick just like you would a power chair. In Handrim Steering mode, you use the handrims to steer like you would a typical manual wheelchair, though you still control speed and acceleration with the joystick. Handrim Steering mode does give you the option to slow and stop yourself by braking with your handrims. 

The joystick is wirelessly connected, which seems a curious choice given SmartDrive’s issues with Bluetooth connections. I, for one, would want to be able to slow down with my handrims anywhere but wide-open paths. Sunrise says that the connection is safe and stable, so it’s up to you how you feel about wireless control for a powered wheelchair. 

When you want to push your chair yourself, you can turn a dial on the wheels to “free roll,” so they’ll roll like a normal, albeit heavy, set of unpowered rear wheels. Those wheels are a lot lighter than other powered options though. The M90s weigh in at 13 lbs. per wheel, with the battery pack attached, compared to about 15.5 lbs. for the Yahama NaviONE and 17 lbs. for the Alber e-motions. The Power-Flex, which is the most functionally similar to the M90s, weighs a whopping 115 lbs.  

As for other specs, the M90s have a top speed of 3.7 mph and an estimated range of 9.3 miles, depending on your weight and the type of terrain you’re covering. That puts the M90s at the same max speed as the NaviONE and e-motion wheels, but less than the PowerFlex’s 5 mph top speed or 12-mile range. One advancement on the M90s is that they have small, 1.3 lb. quick-release batteries, so you can carry multiple battery packs and swap them out.  

All-in-all, the M90s look like an interesting addition to the quickly-expanding world of powered mobility accessories. At 26 lbs. total weight, they’re the lightest and easiest to transport way yet to add power wheels to your manual wheelchair.  

The M90s retail for $7,950, though you can find them online for about $6,300 — a few hundred more expensive than you can get a pair of e-motion M25 wheels, or a few thousand less than a Power-Flex. 

For more information on the M90s, you can visit Sunrise Medical’s website.