The Tern Node D8 with BionX is a mid-sized folding electric bike with larger 24″ wheels meant to smooth out the ride and improve handling. It features a higher end drive system from BionX that’s durable, powerful and quiet to operate in a range of modes including pedal assist and throttle. Even with the battery attached, the Node folds completely but you can opt to remove it for reduced weight or convenient charging. Both Tern and BionX are respected manufacturers, known for quality builds and good support. In my opinion they’ve created one of the most functional, well balanced and beautiful folding electric bikes around with the Node D8. Depending on your needs, they offer a very similar ebike called the Link D8 that uses 20″ wheels allowing it to become even more compact when folded. Either bike performs well and the Link is $50 less, but overall these are higher end and that’s reflected in the price and 5 year frame, 2 year drive system warranty.
The motor driving the Tern Node D8 electric is a 350 watt gearless direct drive hub from BionX. It’s located in the rear wheel for improved traction. Note that this motor has a larger diameter and higher weight than some equally specced gearless hubs but delivers increased toughness and quieter operation. I’m not aware of many folding electric bikes that offer regenerative braking or regen modes but the Node D8 with BionX has both. There are actually four levels of regen here to help you recapture energy while simultaneously slowing the bike and sparing your brake pads when coasting down hills. This feature can also be used as a form of increased challenge if you want to raise your heart rate and don’t have any hills around to climb. While this bike does not have a rear quick release mechanism (only on the front wheel) the rear wheel is still easier to service because the motor has a built in torque sensor vs. an external dropout strain gauge.
Powering the Tern Node D8 is a BionX made Lithium-ion battery pack containing Panasonic cells. It offers 48 volts of power which is above average. This has several benefits including increased torque, improved climbing ability and more efficient electricity transfer. In terms of overall capacity, this pack is slightly smaller than the stock BionX kits but that enables the folding-with-battery feature mentioned earlier and keeps the overall weight of the bike down. At 45 pounds (with the 6 pound battery attached) this isn’t the world’s lightest folding ebike but that’s due in part to the high quality fenders and rack that add utility. You could always remove these extras to shave a bit off and reduce any rattling noise that can develop over time with use, folding and storage.
The control panel on this bike is one of my favorites because it’s slim, removable, backlit and packed with readouts but not overly complex to use. It’s a second generation display from BionX with four buttons (two on each side) that are symmetrical, designed to be usable on the left or right hand side. What I’ve found is that I usually only press the upper right hand button on the display to get the bike powered up and then rely on the stand-alone button pad and throttle which are mounted on the right handle bar. Many ebikes forego throttles but it can be useful when your legs get tired (especially on a smaller bike like this) or trying to balance groceries and packages. The rear rack helps with this but you get the point… imagine crossing a puddle and wanting to keep your feet raised temporarily but still needing to move forward, that’s where a throttle can really shine. On this system (as well as other BionX) you have to get the bike up to 2 mph before the throttle will activate and this is a safety feature.
Aside from the display and buttons I like the ergonomic grips and simple grip shifter on the right side of the handlebar. I’d consider adding a bell and lights to this setup depending on your intended use. I should mention that only the right brake lever has a motor cutoff and regen activator built in. If you brake with the left lever, regenerative braking will not activate. This is a minor gripe and again, a design feature related to all BionX kits at the time of this review. Other grips include basic grips (no lockers to keep them straight), basic plastic folding pedals vs. aluminum, basic v-brakes vs. disc (they get the job done pretty well and keep the price down), and lack of suspension or the ability to add a seat post shock due to the extra-long length required.
The Tern Node D8 with BionX combines two proven platforms. The quality locking mechanisms and folding design from Tern are superb and I love the magnetic clasp meant to keep the bike from unfolding. The silent and durable motor from BionX feels zippy and the removable battery is convenient. I’m a fan of pedal assist but see the value in throttles so it’s nice that this folding ebike offers both. The eight speed cassette provides good range for climbing or pedaling fast (which is less wobbly on a bike with larger 24″ wheel size). I like the reflective sidewalls on the wheels and the Kevlar lining to deter flats. The crank arms on this bike are actually quite long for a smaller bike and that makes pedaling feel natural. While many folding electric bikes opt for rear mounted batteries I love that this one has a more balanced weight distribution combined with a “full frame” feel that doesn’t feel squished. If you’re looking for quality and can trade some space for improved ride quality then the Link D8 would be an excellent choice. It would be useful on an RV, Boat or cabin where space is limited but you plan to bike frequently and for longer distances.
- Solid two year warranty on the frame, drive system and battery pack – Tern and BionX are both large, well established companies
- Beautiful aesthetic with matching black and blue frame and black battery casing featuring co-branded Tern + BionX art
- Just about every drive mode you could ask for including four levels of torque sensing pedal assist, four levels of energy regeneration and variable speed trigger throttle
- Independent button pad on right side of handle bar is easy to reach (to change assist mode or use the throttle) doesn’t require that you take your hand off the grip to use
- Battery pack can be charged on or off the bike, does not have to be removed for the frame to fold completely
- Motor is powerful, durable (thanks to the gearless direct drive configuration) and very quiet to operate
- Full length front and rear fenders with mud flaps, rear carry rack includes built in bungee cords for securing cargo
- Several nice extras including reflective sidewalls on tires and backlit LCD display panel for improved safety during evening and night riding, ergonomic grips for improved comfort and magnetic clasp for secure folded position
- Good weight distribution with the 9 pound hub motor at the rear and the 6 pound battery pack mounted forward on the downtube
- BionX battery has a deep sleep protection feature that keeps it from discharging in a way that could hurt the battery over longer periods of storage
- Satisfying to pedal thanks to the longer crank arms and eight speeds cassette, good for climbing or riding faster
- Larger 24″ wheels provide a more comfortable ride and elevate the frame for larger riders but limit how small this bike can get when folded, consider the Tern Link D8 if space is very limited in your intended use
- Only the right brake lever cuts power to the motor and activates power regeneration mode, it would be nice if both did
- Rear wheel does not feature quick release, will have to use traditional tools during maintenance or fixing a flat