Sur Ron is a new light electric off-road electric motorcycle. I feel a little odd calling it a motorcycle, but it doesn’t have pedals (without pedal kit from Luna Cycle), so it isn’t an ebike.
Dragon Light Bee?
In China, this model is being marketed as the Dragon brand, “Light Bee” model…this reminds me of a time back in the early 1970’s (yes, I AM that old) when the Japanese global Nissan corporation wanted to name their new sporty 2-seater the “Fairlady”, but..their US distributor (Yutaka Katayama, or…”Mr K”) knew that the name “Fairlady” would not inspire young men in the US to buy their sports car, so…when the cars arrived in the USA, he secretly had their badging changed to the “240Z”. It ended up being a HUGE success.
The Dragon “Light Bee” is also destined to be a success in the USA, but here? it is named the “Sur-Ron Firefly”. Shakespeare wrote that “a rose by any other name is just as sweet”, so…let me just say…regardless of the name its marketed under, I think this model will do quite well in North America.
Luna Cycle is selling a 60v version with some performance hop ups as the Sur Ron MX.
It might “only” have 6000W of power, but…that amount of power is packaged in a light and well-designed frame that can take hard off-road jumps with ease. By having a large RPM reduction between the motor and rear wheel…the amp-draw demands on the battery are lowered, and the motor also runs cooler.
A graphic of the 2-stage Sur-Ron drive.
As you can see from the PR pic above, the Sur-Ron uses a 2-stage drive. The first stage uses a belt to make the high-RPM’s quieter, and the second-stage uses a chain to manage the high torque that is being applied to the rear wheel. By having a 2-stage drive, the motor can run at very high RPM’s, which helps the input power to remain as efficient as possible, while still providing the target “wheel power” with as little motor heat as possible. If the total reduction in RPM’s from the motor to the rear wheel was accomplished with a single stage, the tiny motor drive-sprocket would be very loud, and the rear wheel sprocket would need to be huge.
Also, the Sur-Ron uses an “Axial Flux” motor from Golden Motor, the HPM 3000B. Each design consideration has its benefits and drawbacks, and …the choice of an axial flux motor (as opposed to the common radial flux) means that they want the most power in the smallest package possible.
The core of any electric vehicle is the battery and motor, and this light dirt bike has a very large 32-Ah pack using 60V, and it is made from the highly respected Panasonic PF cell. The cells are configured in a large rectangular box that easily slides out of the frame if you ever want to remove it. Of course, most owners will charge the battery with it located in the frame.
A recent battery pack tear-down showed that it is definitely 16S / 11P, so the cells are 2900-mAh each.
The Sur-Ron battery pack, 16S / 11P, pic courtesy of Allex in Sweden.
One of the benefits of electric vehicles is that they perform well even in bitter cold, where starting a gasoline engine in freezing weather might be difficult (Tesla car sales are doing great in Scandinavia) . If you own a Sur-Ron that you park outdoors and live where it snows, that is one user-profile where you might want to remove the battery for charging indoors. That way the battery will stay warm, and ready to go when the mood to ride strikes you…
It’s obvious from the first glance that the Firefly uses heavy-duty off-road bicycle components to outfit the frame, which keeps the weight and costs reasonable, but…the frame is a custom unit, specifically designed for this particular job.
The rear swingarm uses forged aluminum to make it as light as possible, while still being strong enough to do the job of taking significant jumps. The shape and placement of the rear shock provides a very long stroke, and it appears the geometry of all the frame components are taken from the very mature dirt motorcycle designs that are common.
The Sur-Ron MX Light Bee, pic courtesy of Micke from Sweden
The shock is actuated by an additional linkage to help make the compression as progressive as possible. This means that in the first half of its compression, the swingarm response to road irregularities is very light and sensitive (which provides a smooth ride when riding fast) and the second half of the shock compression is much stiffer, which is necessary for those times when you take a big jump.
This mature “dirt bike” geometry and progressive suspension is the reason some riders will prefer a dedicated dirt frame that doesn’t have the pedals of an off-road electric bicycle. On a dirt “ebike”, the need to place the pedals where human riders’ feet go, and also the need to connect the pedals to the chain-drive…both will force compromises in the design so that it could never quite perform as well as a dedicated design.
Of course, you can’t pedal home on a Firefly if you ever run the battery out. Fortunately, it does have a very large battery.
This is a growing field that is booming this year. Electric off-road motorcycles are very quiet, and can be ridden close to residential homes, in places where a gasoline dirt bike would have the neighbors complaining about the noise. They don’t require a license, since they are ridden off-road on private property.
Modern lithium battery systems are now very safe, and I would rather have my teenager storing one of these in my garage than have them filling a gasoline dirt bike from gas cans (remember that?). Ever since I bought an electric grass mower and weed trimmer, I have gotten rid of the splashy gas can in my garage, and I feel much safer.
The components that will wear out on this model are the tires, brake pads and discs, plus the chain. However, these are all heavy-duty mountain bike “bicycle” parts, which are cheap and easy to source…much cheaper than “motorcycle” tires, brakes and chains. Speaking of wearing out, Tesla has shown that a properly designed electric motor will last the equivalent of millions of miles. The only motor parts needed for a rebuild are two shaft bearings, which are cheap and easy to swap-in. Compare that to a gasoline dirt bike engine…
We already wrote about the Kuberg, and it is probably the closest of the models below to being in the same category as the Firefly, because it also uses a lot of off-road bicycle components.
The Kuberg off-roader.
I think the Firefly looks better, and it definitely has more power with a better suspension. That being said, the Kuberg will fit some younger riders better, since the Firefly is a little taller. Both are priced very affordably.
I think the LMX 161 will give the Firefly some competition. It is hard to get right now, since it is made in Europe, and they are difficult to import. Time will tell.
The LMX 161
The Oset 24R is a great off-road E-moto. The company has E-moto’s in a variety of sizes, so if your family has some younger riders, the smaller Osets may be the only ones that fit them (the 12.5, 16.0, and 20) . The Oset 24R is their largest, and is set up as a trials bike, so it is intended to be ridden while standing, meaning that there is no seat, but…I’m sure you could bolt on an aftermarket seat. The battery is a 48V and…the fat tires are normally ridden at low pressure to help with slow obstacle crawling. This system is set up for low speed and high torque, to emphasize trials competition performance. Search youtube to see what trials competition is…very fun!
The Oset 24R
The downsides to the Oset 24R compared to the Firefly is that the Oset is much more expensive (MSRP $4,299), while having less power. It does have a mid-mount motor, instead of a hubmotor. If you place the motor in the rear wheel, it increases the unsprung weight, which affects the balance and suspension rebound on jumps. Also, by having a mid-mount motor…the motor can spin many times faster than the rear wheel. The Oset has a single-stage chain from the motor to the rear wheel. This is MUCH better than a hubmotor, but…not as good as the 2-stage drive on the Firefly.
The Firefly uses a 60V system driving a very high reduction, while the Oset uses only 24V driving a single stage. This means that for less cost, the Firefly will have more power and range.
KTM Freeride E-XC
The KTM Freeride E-XC
The next three models are the most serious competition for the Firefly from a performance angle. These are truly serious machines which use true motorcycle tires, chains and brakes, but…the drawbacks are that they are heavier and more expensive. The KTM Freeride E-XC can be found here. It is from Austria, and since they have a limited production, it would be hard to get your hands on one in North America. The 2018 model is all new, and the result of the lessons they learned on the previous models.
The purchase price is 7400-Euros ($8944 at today’s exchange rate), but…that does not include the battery pack, which can only be leased (US price is yet to be determined).
Alta Redshift MX
Retail MSRP on the Alta Redshift MX is $14,990…and it can be found here. I hear it is a truly great E-moto, but…$14,990…
The Alta Redshift MX
The Zero FX is selling quite well, along with their street-legal version. the MSRP is only $8,495…and if you want a full day of off-road riding, you can buy spare battery packs that are easily “hot swappable”. The Zero FX can be found here
The Zero FX
Where to get?
The Sur-Ron Firefly is available from Luna Cycle in Southern California. Some of the competing models listed above are more powerful, but…also heavier and more expensive. Other models listed above are near the same weight, but less powerful and still more expensive. The Sur-Ron Firefly occupies a pretty sweet spot in the lineup. It is a good looking off-road E-moto, and I think 2018 is going to be a very good year for the Sur-Ron Firefly.
The Firefly provides a great balance between performance and cost.
What to expect?
Here is a recent edit. I finally found a forum post about a new Sur-Ron customer, and I thought potential owners would appreciate seeing some info on a new purchase. Click here to see the discussion.
If you want even more information about the Sur-Ron, here are some walk-through videos that cover quite a bit of detail.
The BEST ugrade
Get the Luna Cycles 60-tooth sprocket. It is available in aluminum for light weight, but…I recommend the stainless steel sprocket for long life. Here is what my friend Karl has to say about that…(Click here for Karls article on the 60T sprocket).
Also, there are rubber bumpers around the front suspension fork tubes, that hit the frame when you turn all the way to the right or left. They can be easily rotated so that the thick part doesn’t hit, which means you can then turn a little farther to the left or right. Some riders like this, so maybe try it out and see if it fits your riding style.
Written by Ron/spinningmagnets, January 2018