A 1500W hub motor for a front wheel on a 26-inch fat-tire bike is extremely rare and unheard of at this price point. Most kits around this price range max out at 750W or 1000W and are typically sold as rear wheels. The Helrgelrn 1500W front conversion kit puts 1500 watts to your front axle and expects very little back from it. Also, the kit is designed specifically for 26x4 inch fat-tire frames. Trail bikes, beach cruisers, winter commuters. Bikes that weigh heavily and move slowly. They would require a mid drive kit, with the associated cost. If that describes your bike, read on.
Specifications and Build Quality
At the center of the Helrgelrn 1500W is a gearless brushless hub motor rated at 1500W continuous on a DC48V system and 520 rpm on a 26 inch wheel. Gearless hubs are the workhorse of conversion systems. With fewer moving parts than a geared hub, they are less likely to vibrate loose. Even at higher weights, they produce plenty of force on hills. Two items in the specification sheet stood out to me as I reviewed the specifications. Sine wave control, meaning smooth and quiet power rather than the abrupt start/stop motion of earlier square-wave controllers. Secondly, the ability to operate either with Hall or non-Hall sensors. Should the Hall sensor fail during a ride, the controller will automatically switch to a non-Hall sensorless operating mode and allow you to continue riding. Any rider who has ever had to limp their way home due to a failed Hall sensor understands how valuable an automatic switch like this can be.
There are also five adjustable speed levels available. So you are not pre-programmed to a single rate of climb. Cruising on the board walk or sprinting home, you can choose whichever setting fits your mood. Cruise control is also included, another nice touch many budgets don't provide. Choose your desired speed, remove your hand from the throttle, and the motor will maintain it.
The control head is a VA color LCD display with gear, speed, mileage, and battery state displayed in color. No longer will you be forced to squint at an LED brick with only three characters. A brake lever cutoff switch with auto motor shut-down is also included and will turn off the motor as soon as you squeeze the lever. All of this operates using DC48V, therefore you will need to purchase a 48V battery and controller in conjunction with this kit, unless you already own them.
Performance and Power
As mentioned above, the performance of the Helrgelrn 1500W is dependent upon several factors including, but not limited to, the rider's weight, air pressure within the tires, and elevation changes. However, the manufacturer quotes a maximum speed of approximately 31-37 mph based upon optimal operating conditions. In layman terms, that translates to fast. Commuter fast? Grocery run fast? No. Hold on to your seat fast. You may experience the low end of this speed range when carrying a high amount of weight on your fat tires, however there is sufficient reserve power for you to achieve the upper end.
The 1500W rating of the motor provides ample torque to get a heavy fat tire rolling from a stop and to maintain speed going up a moderate hill. As stated previously, this is far beyond what a 500W kit could hope to accomplish on such a vehicle.
For commuting purposes, the benefits are apparent. Since the motor resides at the front of your bike, it pushes while keeping your rear drivetrain intact. Therefore, you won't have to deal with chains, cassettes, or derailleurs. You will still retain the gearing you already have. Additionally, since the motor resides at the front of your bike, you will still be able to enjoy stable handling on your long wheelbase fat bike.
In regards to hill climbing, the 1500W rating of this motor allows it to dominate the rolling hills that most riders encounter daily. While geared hubs and mid drives will certainly have advantages when climbing steep hills, a large gearless hub motor at this wattage will make quick work of rolling hills.
Installation and Build Considerations
I'm going to give it to you straight. Installing a front hub motor isn't quite as simple as installing a mid drive motor. It requires some mechanical effort. You'll replace the front wheel with a motorized front wheel and secure it in place by tightening the nuts on the fork dropouts. If you're planning on purchasing this kit at a premium, it would be highly advisable to purchase a torque arm as well. Without one installed, your front axle can easily spin out of alignment in the dropout under load and damage your fork.
Once you've secured the motor wheel in place via the torque arm, if purchased separately, then comes the wiring portion. The controller attaches directly to the motor wires, the battery connections for charging, the throttle connection, PAS sensor connection, brake lever cutoff connection, and finally LCD display mounting to your handlebars. Each of these connectors attach to each other in a fairly standard configuration. However, ensure that all cables are routed neatly behind your stem and are sufficiently slack for full lock to lock movement without straining a cable. This is generally considered one of the major mistakes rookie riders make and results in snapping a connector after a couple months of service.
Finally, waterproofing merits mentioning. While hub motors are sealed units themselves, moisture can enter at various points throughout your system including the controller unit and connector areas. Many builders will seal their controller unit inside a dry bag and apply dielectric grease to their connectors for added protection. Given the price point of this kit, I'd advise spending a small amount of time considering ways to add additional protection measures yourself.
Who Is This Kit For?
This kit is intended for someone looking to convert their 26 inch fat-tire cruiser or trail bike into an ebike with actual power without altering your drivetrain. It's for individuals that prefer simplicity at the front wheel, have access to a readable color display, and desire 1500 watts on tap without breaking the bank.
Again, this is a relatively new product with no reviews yet. So please keep expectations reasonable until some miles get accumulated. Although the specification sheet looks great and there are numerous features included with this kit for the price, ultimately a hub motor kit is only as reliable as its real-world dependability. When purchasing an unreviewed kit, always shop with sellers that have a reasonable return policy and keep all original packaging until you've logged hundreds of miles on your ebike.
To better understand how this kit compares to other conversion kits, check out our ebike conversion kits comparison table. For more information and reviews from people that actually run similar conversions, visit the gomotorbikes blog.
Frequently Asked Questions
Will the Helrgelrn 1500W kit fit any 26 inch fat tire bike?
This kit was developed for 26 x 4 inch fat-tire wheels and thus is targeted towards bicycles utilizing this size tire in their frames. Please always inspect your fork's axle width and dropouts prior to ordering, as different manufacturers design different types of fat bike front axles.
What type of battery and voltage does it utilize?
The motor utilizes DC48V, thus you will need a 48V battery and compatible 48V controller. If you're creating an ebike from scratch, consider factoring in costs for these two components as well.
How fast will it actually travel?
Manufacturer estimates quote an approximate speed range of 31-37 mph depending on terrain conditions. Keep in mind that actual speed is dependent upon multiple variables such as rider weight, air pressure in tires, terrain conditions, and wind resistance, so anticipate achieving speeds closer to the lower end of the estimated range with loaded fat tires.
What exactly does sine wave control do?
Sine wave control produces smoother, quieter power compared to older square-wave controllers. Less abrupt lurch when twisting the throttle, less aggressive acceleration, and an overall more refined ride feel.
What happens if my Hall sensor fails?
The controller supports both Hall and non-Hall operation modes. Thus if the Hall sensor fails during a ride, the controller automatically converts to non-Hall sensorless operating mode and allows you to continue riding.
Does the kit include throttle and display?
Yes. The kit includes a VA color LCD display showing gear, speed, mileage, and battery state, as well as a braking lever with auto motor shut down feature. The motor powers off instantly upon activation. Please confirm the exact contents of the box prior to ordering.
If this appears to be the correct kit for your fat-tire build, check out the current listing for the Helrgelrn 1500W front kit on Amazon for full details.