A “freeride” bicycle is used to go up a steep hill, and the hill is so steep that when you start to go downhill, you pretty much don’t need to pedal at all.
_____________________________________________
Adam Mercier lives in beautiful Lyon, in eastern France (near the mountainous Swiss border). LMX has grown, and now his business partner is Lucas Suteau.
______________________________________________
How They are Made
It would be easy to assume that any new ebike has its frame made in China to save on costs, but Adam has firmly decided that he must make the frames in France. Of course the forks, shock, wheels and other standard bicycle components are sourced from Taiwan, China, and other common suppliers, but the unique part is the frame, and Adam needed it to be strong and also very light.
After welding the aluminum frames, they are heat-treated in a large oven. Then the frames go through T4 quenching, then a T6 phase. It would be a little cheaper to have the frames made in China, but since Adam insists on making them himself, he has complete management over quality-control. This also eliminates shipping delays, along with any supply glitches due to international trade disputes.
The downtube uses a cradle-interface for the common 52V shark battery packs. There is room to use a larger pack, but Adam feels its better to use several small batteries for a day of riding instead of a larger one, so the LMX64 can remain as light as possible on the high-speed downhills that he loves.
_______________________________________________
The Drive System
When designing a mid-drive ebike, it can be helpful to give the motor the use of the gears in the rear wheel. Doing that would allow the motor to efficiently run at the highest possible RPMs by downshifting when you arrive at a steep uphill.
However, if you are running the motor-power through the bottom bracket, This can put a lot of strain and wear on the bicycle chain and sprockets, leading to a frequent replacement of those components. Adam felt that if he had enough power, the motor would not need any gears, even for very steep sections. The latest version is rated for 2000W of peak power.
The V2 in the pic below (from 2009) has a single-speed freewheel for the pedals, located at the rear wheel’s axle. The motor-drive uses a large sprocket that is firmly fixed to the rear wheel, so the motor does not put any strain on the pedaling drivetrain. A freewheel for the motor is located at the motor in this version, so the motor does not have to spin when he is rolling downhill.
I’m mentioning the V2 because it shows that he has been experimenting for many years, and Adam is not new to this.
Adam refined his original prototypes, and once he was happy with the two parallel and separate drivetrains, he decided to move the motor-drive to the left side. In the pic below, the chain is managed by two red idler-wheels and chain-guides. The top idler is in a fixed position, and the bottom idler swings under spring-tension in order to keep the chain tight as the rear suspension cycles up and down.
The motor is available with either a 12T or a 14T drive sprocket. The 14T would have a higher top-speed, but less wheel torque, and also…the 14T would run quieter. The chain is the #219 type, which is famous for being used on very high-powered racing Karts.
The #219 chains also have the feature of using smaller links than a standard bicycle chain, which allows the designer to package a very high reduction into a single stage from the motor to the rear wheel. When using the 100T sprocket on the rear and the smaller 12T on the motor, it has an impressive 8.3:1 reduction.
By moving the motor from the wheel to the frame, it improves the “unsprung weight”. This allows the rear wheel to be as light as possible, and that means it can respond to bumps and jumps much better than a heavy rear hubmotor.
By mounting the motor in the frame, we also have the option of spinning the motor much faster than the rear wheel, by adding some type of RPM-reduction. This means that we can use a smaller and lighter motor to achieve the same power, and then simply spin it much faster than the wheel to get the same wheel-torque. Doing that also has the practical effect of lowering the amp-draw of the battery pack, while still providing the same wheel-torque as a large and heavy hubmotor.
The debate between hubmotors and mid-mounted motors will likely continue for the rest of my life, but for trails that have serious jumps and technical sections that require an experienced and subtle hand to navigate, a lighter ebike will often be much more satisfying.
The pic above shows the right side of an LMX64, and it highlights a well-regarded close-ratio 11-speed derailleur. This allows the rider to find the “perfect gear” when pedaling up a hill with a constantly changing grade. The small chainring means that the stock gear ratios will not be useful at higher speeds, however, they are designed to give the rider the greatest number of options for the uphill climb.
This picture above, also shows the optional license-plate holder. I made sure to add a picture with this feature, because LMX will soon pass its homologation testing to become a street-legal moped/enduro in France (ebikes in the EU with no moped license have a 250W-500W power limit, depending on the country, and the LMX64 uses 2000W). Of course that “street” version would have street/dirt “dual-purpose” tires and a headlight, among other details.
_______________________________________________
Many young Americans love motocross, but the Europeans have been in love with motocross long before the US, because they invented it. The word stands for MOTOrcycle CROSS-country, and the MX in their name stands for motocoss.
I think this is because in the early days of motorcycles, it was easier for Americans to hot-rod on public roads, but the European cities had more restrictions. This meant that if a young man from France wanted to ride a powerful motorcycle as fast as he could, his best option was to go off-road.
Below is a short youtube of a mountain bike competition in Kluisbergen, Belgium. The LMX won first place against several more powerful ebikes, and Adam credits this “win” due to how light and nimble the LMX64 is.
Here is a map of central Europe, showing where Lyon is located. European customers may have to pay a Value-Added-Tax (VAT), which is a sales tax to support the social programs in Europe. USA customers do not have to pay the VAT, but…they do have to pay a very high shipping cost if you want to own an LMX64…
Here is a recent 2019 LMX64 video.
_______________________________________________
Written by Ron/spinningmagnets, November 2019
