OHM Sport XS750 15 Review

The OHM Sport XS750 15 is a hard core urban style electric bike with the potential to work well as a touring or trekking platform. I think of it more as an urban platform than a road or city bike because it’s got a burly front shock and large balloon tires… almost like OHM took a mountain bike build and then swapped out the stem and knobby tires for something more upright and efficient. It all comes together very well feeling sturdy and offering the torque and power that’s critical for toting larger loads or attacking steeper hills like those found in San Francisco (where I tested the ebike in the video review above). OHM is actually a Canadian company that designs custom frames to be used with leading drive systems (BionX in this case) and then outfits them with the appropriate accessories. In this case you can get full length fenders, integrated lights and a sturdy transport rack (capable of managing 65 pound loads!

Driving the bike is an impressive BionX D-500 motor (the largest and most powerful that the company made at the time of this review). Just look at it, this thing was made with one thing in mind… torque. It’s a gearless direct drive motor which means that in order to create mechanical advantage, it needs to be wider (or use stronger magnets) to create the same drive characteristics as a planetary geared design. The benefits are that operates extremely quietly (like most gearless motors), is very durable (no moving parts inside) and can offer regenerative braking and regen (to recoup energy when coasting down hills or add a challenging workout element to your ride on flats). There are some trade offs however and one is the aesthetics, this thing screams “I’m an ebike” which not everyone likes. It also presents a larger surface area for catching crosswinds (much like deep dish rims but less pronounced since it’s the rear wheel which doesn’t steer). The final drawback to this and any gearless direct drive is cogging, that is it slows more quickly when coasting due to repelling magnets inside. All in all, it’s a solid motor and one uniquely catered to offer strength.

Powering the motor, backlit LCD display panel and optional headlight and backlit is an efficient 48 volt 11.6 amp hour battery pack. At nearly half a kilowatt hour this thing can either power you up hills in throttle mode for something like 20 miles or take you on far away excursions for up to 80 miles (in the lower assist levels). The cells inside are Lithium-ion, light weight and long lasting, and come with a reasonable one year warranty through OHM. BionX sells this same motor/battery kit directly to shops for do it yourself DIY conversions and offers a two year warranty on manufacturer defects so you might be able to follow up with them if issues arise. At the end of the day, it works pretty well and is connected to the frame in a great location – low and center. I like that it’s locking and removable for easy charging off the bike… perfect for commuting. It matches the black paint on the bike nicely as well and it’s neat that OHM designed all of the cables to be internally routed because it’s clean and sleek with fewer opportunities for snags along the way. To really care for this or any Lithium batter pack it’s best to store at 50% or more charged and in a cool dry location. Check on it ever few months to make sure it isn’t running dry as that can be hard on the chemistry long term.

One of my favorite parts about the BionX electric bike system is the user interface. Once the battery pack is charged and seated properly you can activate the bike by pressing the top left button on the display pad. You’ll see a battery level and speed indicator come to life but most of the screen real estate is taken up with a set of eight bars that show four regen and four assist levels. By using the up and down arrows on the right side of the display or the up and down arrows on a remote button pad mounted near the right grip you can navigate between these eight bars and the drive system responds almost instantly. It’s very intuitive and even usable without looking at the display once you get the hang of it. At any time you can also override assist by pressing a little red trigger at the base of the button pad. This feature is especially useful for topping hills or getting an easy start after stop signs and traffic lights. I tested the climbing ability on some hills in San Francisco using the trigger throttle and was very impressed with the overall power and smooth acceleration. Note that you need to be moving ~2 mph before the throttle will activate, pedal assist is more immediate and this is an intentional design decision emphasizing safety. Another cool feature with the display is that it’s easy to click off and take along with you. I tend to remove my displays and batteries when parking in public spaces or commuting to work… it reduces sun and rain exposure, allows me to charge the battery and deters vandalism or theft.

The OHM Sport XS750 is an impressive and fun electric bike. Ergonomically it feels nice because the handlebars are higher and less far forward than other competing products with similar tire/suspension features. I like how light it is at ~46 lbs and the fact that you can get it in four sizes for a perfect fit. The black color is cool and timeless and even though the motor is large like some kind of amazing pizza in the rear wheel, at least it matches the rest of the bike. You get every drive mode you could ask for with this bike and a solid top speed of ~20 mph for a really decent price ~$4k considering the quality. I’m a big fan of suspension when riding through urban environments because cracks, potholes and curbs tend to be jarring at high speed and over longer distances (more time in the saddle). The larger tires and oversized fork really help but there are similar full suspension offerings out there such as the Focus Thron Impulse Speed (it also reaches higher top speeds but lacks the throttle mode… and costs $2,600 more). I like BionX stuff and I like OHM, this e-bike did not disappoint and is one of the few purpose built offerings with the D-Series motors that I’ve tested or am aware of. It seems like everyone has had that moment discovering electric bikes where they wonder if you can charge the motor by pedaling and indeed, with this ebike you can… and it works pretty well. Still, I think it’s best suited as an engine brake when coasting back down the steep hills that the motor helped you ascend, it will definitely save your brake pads. As a final thought, the hydraulic brakes with 180 mm rotors on this bike are also worth highlighting because they provide smooth solid stops and that can be another necessity for larger riders or those encumbered with extra gear.

Pros:

• Amazing wheels and tires, you get kevlar lined Schwalbe Big Ben’s with reflective sidewalls (extra large for improved comfort and durability) in 27.5″ size which is a nice happy medium that works well with suspension but is also efficient and steady over bumps
• The battery pack and display panel are both removable which makes the bike lighter during transport and also deters wear and theft when parked outside or in public spaces
• The display panel is backlit for use in limited light and symmetrical so people who are left or right handed can interact with it more comfortably, it also swivels front to back to reduce glare
• I really like how intuitive the display panel is on the BionX system, you’ve got four regen modes, four assist modes and a throttle that works at all times and offers variable speed output, it’s clean and intuitive
• Great accessories here including full length plastic fenders (with mudflaps and extra struts for strength), a rear rack, nice adjustable kickstand, bell, locking grips and integrated lights
• Available in four frame sizes for improved fit, the sloped top tube is nice when standing over the frame but is still very strong and stiff compared with a low step
• Decent suspension fork with lockout, great hydraulic disc brakes which are easy to actuate with just two fingers (they include motor inhibitors as well)
• The motor is very powerful compared with other gearless direct drive options due to the larger diameter (which improves leverage) but it’s still extremely quiet
• Quality drivetrain, SRAM Via GT with 10 cogs, offering good range for climbing or riding at higher speeds over long distances
• The hollow spindle saves weight, outboard bearings create stiffness in power transfer while pedaling and the chainring has a nice bash guard built right in to protect teeth and your pants from getting greasy :)
• Pedal assist is activated through a torque sensor which means it is very smooth and responsive, this also means you need to push a bit more and pedal actively to get it working in lower assist levels
• Pretty good weight distribution with the battery low and forward, the rear hub motor (though large) is not super heavy

Cons:

• The D-Series motor is so wide that it sometimes catches crosswinds and creates movement in the frame (much like deep dish rims or solid frame bikes)
• When coasting or using this bike with the power turned off there is some cogging drag that occurs as the magnets in the direct-drive motor repel the stater, it doesn’t freewheel like most gearless motors but this is what enables regenerative braking
• For safety, the BionX kit is designed to limit throttle use until the bike is moving ~2 mph, this isn’t exactly a con but I wanted to mention it
• The fenders are very useful but if you are pedaling and making a tight turn it’s possible to kick the front fender because of the larger wheel size at 27.5″ also the bolt-on rack might need to be checked and tightened occasionally to make sure it isn’t rattling loose vs. a welded-on rack

Resources:

• Official Site: https://ohmcycles.com/
• More Pictures: https://goo.gl/photos/5ZyNTTcFEyRdoEoK9