Mecatecno Dragonfly

Advantages and Disadvantages

Although this website is primarily about Electric Motion, the Mecatecno Dragonfly is initially what got me interested in electric trials bikes.

Overall, I think Mecatecno has the right idea - especially regarding the low weight.  The Dragonfly's battery, being held together with screws, looks far more serviceable than EM's.  The wiring layout is far better too - the motor, controller, and battery all connect in the same basic area.  Likewise, it has a much more accessible clutch than EM.  

The downsides are a non-linkage rear suspension and no place for any additional flywheel inertia.  And, of course, completely unknown reliability

The Dragonfly clutch uses 3 friction plates whereas the EM has 4.

Even though the rear shock is a high-quality Ohlins TTX22m.2 unit, it's intended for a bicycle application.  Assuming it survives the demands of moto-trials, I'm guessing it will require more frequent rebuilds than a standard motorcycle shock.

Although I would prefer to have the known quantity of a Tech front fork, the M4 fork is lighter.  The fact that M4 now employs a mechanical spring is comforting to me.

I expect this design will be more appealing to lighter/weaker riders than to heavier/stronger riders. 

You can find user manuals for the battery and Ohlins shock via mecatecnomotorcycles.com as .pdf downloads.

Most of what I'll write about the Dragonfly assumes you have some familiarity with the way EM has done things.  If you are completely new to electric trials bikes, reviewing the EM sections will be helpful.

Some of the information I have found is inconsistent/contradictory.  As I learn more, I expect to reconcile all the differences. 

Credit: The Hell Team

Motor

In Jordi's original YouTube video, he stated that the motor is 15 cm (6 inches) in diameter and weighs only 4 kg (9 pounds).  It makes 15 hp (11 kW) at 10,000 rpm.  Impressive!  

It looks like a QSMotor design, but I could be wrong.

The adjacent screen capture from The Hell Team's video indicates that it uses a sophisticated position encoder (as opposed to simple Hall-effect sensors).  

A parts diagram shows the motor having a pinion gear with 25 teeth.

The motor uses ceramic bearings which require a break-in period, during which time more acoustic noise will be noticeable.

Credit: mecatechnomotorcycles.com

Controller

Mecatecno has some parts diagrams on their website.  This adjacent one clearly shows what appears to be the distinctive outline of a SiliXcon motor controller 

I'm a bit puzzled why the controller is mounted to such a massive heatsink (when the EM is not), but cooler is better than hotter in this instance.

Early on, I had heard the distinctive map tone when the Dragonfly's map button was pressed and hoped they were using a SiliXcon controller.   This is an excellent controller that is perfect for the application.  You can read more about the controller in the corresponding section on the ePure. 

By the way, the source of that map tone is the motor itself - very clever.

Gearbox

Some reviewers have reported the Dragonfly emits more acoustic noise than is typical of an Electric Motion bike.

Another screengrab from the Mecatecno parts diagrams shows a single pair of gears where the gearbox would be on an ICE bike.  This makes sense as the original Dragonfly design had a gearbox.  Now there is a fixed speed reduction, which I am estimating at about 1.5:1, based on counting (sort of) gear teeth.  The EM does not have this, so I would expect some additional noise from this meshing of gears. 

Plus, the motor itself will be running about 1.4x faster than an EM for the same ground speed.  (This is just a rough estimate as the Dragonfly's primary drive ratio is presently undisclosed.)

Credit: mecatechnomotorcycles.com 

Finally, if you appreciate technical details, you will appreciate this excellent video by The Hell Team.  It is an undressing of the Dragonfly.

Dragonfly Assembly Video

Mecatechno produced an excellent assembly video for their special dream bikewhich has a claimed weight of just 54.2 kg (119.2 pounds)!  As of January 2024, the US price is $17,550 and only available by pre-order.

I have embedded the video below.   If you can, watch at a reduced speed to catch all the details.  My comments with timestamps follow.


0:15 We get the first glimpse of the beautiful welded titanium tubular frame.  That's not going to be cheap!

0:24 Here we can see the gearbox shafts on the work table.  Sponsor logos are featured prominently, among them is Dunlop. 

0:51 Heating of crankcase to install gearbox shafts.

0:54 Installation of the gearbox.  Note the paper gasket here (and for the clutch cover).

1:14 Front sprocket installed (at 2:05 we can count 10 teeth).

1:28 Clutch basket seems quite standard.  I'm estimating 75 teeth.    

1:33 Standard S3 clutch pack with 3 friction disks.

1:38 Notice 10 “clutch release arms” (same number as GasGas and others). 

1:53 Paper clutch cover gasket.

2:04 Filling gearbox with 75-weight oil.  No fill or drain plugs are apparent.

3:14 Notice their work stand has been modified to accommodate a securing point through the footpeg.  This is because the skidplate angles up in front considerably.

 4:18 Ouch!  That steering stem nut got gouged. 

4:28 Controller (covered) being installed.

4:51 Motor installed using 3 screws.

4:58 Controller shown uncovered.

5:08 Beautiful carbon fiber handlebars.

6:39 Installation of the special lightweight battery (rated 1750 Wh).

6:42 Main fuse evident in the battery positive cable.

7:04 Display reads 38%, 50.0V, 31° C.

7:21 List of special parts.

Overall Gearing Estimate

Based on observation, manufacturer claims, and educated guesses I think the following is close.

Secondary: 10T front sprocket drives 44T rear sprocket for a 4.4:1 ratio.  The chain size is 428.

Primary: 25T motor gear drives a 75T clutch basket gear for a 3.0:1 ratio.

Transmission: I'm estimating this at a 1.5:1 ratio. 

Overall: 4.4 x 3.0 x 1.5 = 19.8:1

This yields a top speed of about 63 km/h (39 mph) given a standard trials tire at a claimed maximum motor speed of 10,000 rpm.

The US importer says he observed a GPS-measured top speed of 46 mph.  This would imply an overall gear ratio of 16.9:1.

For comparison, the EM Race (before 2024) had an overall motor speed reduction ratio of 14.39:1 and a measured motor maximum of 8,160 rpm.  This yields a top speed of about 70 km/h (44 mph) with the same tire dimension used for the Dragonfly calculation.

Firsthand Account

A friend (Mike) who is a current EM Race owner was able to obtain a brief test ride on the Dragonfly.  There was about a half meter of snow on the ground, so time on the bike was limited to the public road and owner's driveway.  The following information comes from that ride. 

By far the most impressive thing is the low weight.  Mike found it very easy to balance, and full lock turns were no problem. 

The controller has not yet been updated to the latest specifications and thus lacks the automatic anti-reverse, and also something I would call a virtual flywheel on deceleration.  Remote updates of the controller firmware are possible.

There is no tick overor idle feature.  It does not feel as though there is any automatic regeneration and there is no button to manually cause regeneration.

Mike said the throttle response was nice.  It may accelerate faster in the Green and Blue modes than Mike's 2022 Race.  He did not try Red mode.  There is no controller neutral.

The clutch feels about the same as the EM but was not adjusted to Mike's liking.  The clutch uses GasGas plates, so their various thickness steel plates would be available for tuning. 

Having not seen a drain plug, I was curious about changing the oil.  The oil comes out where it goes in.  Lay the bike on the left side to drain, and the right side to fill.  It uses about four ounces (120 ml) of the fluid of your choice.  

The sound it makes is different than that of an EM - maybe more mechanical”.  It is not loud and Mike felt he could still hear what the rear tire was doing on hard surfaces. 

One of Mike's concerns was the rear master cylinder being vulnerable in a crash.  Mecatecno is aware of this and says it's more rugged than it appears and can withstand a lot of abuse.   

Parts are not expensive.  The bike has already needed a replacement rear fender for $60.

There is a 2-year warranty on the bike, but only 6 months on the battery.

Note that Mecatecno's battery capacity claim is roughly 15% greater than the battery manufacturer's rating.  This is because Mecatecno uses the battery's maximum voltage whereas the battery manufacturer uses a more depleted value.

Bottom line: the test did not reveal anything that would stop Mike from buying one.  On the other hand, it was not so fantastic that he planned to place an order immediately.  Mike would like to test the bike at one of his riding spots.  That would settle the buy or not buy question.  But that's months off given the weather.  Mike would probably keep his EM even if he gets a Dragonfly.

Miscellaneous Observations

There is no conventional 17-character VIN (vehicle identification number) on the headstock.   Each bike is uniquely identified by markings near the countershaft sprocket.

On the same hanging scale, a 2022 EM Race weighed 170 pounds.  The 2023 Dragonfly weighed 137 pounds (6 pounds lighter than I was told by a different source using the same procedure).

There is no DC-DC converter.  Power for the LED headlight comes directly from the controller (via a 10-volt output). 

The Dragonfly uses a standard motorcycle lanyard kill switch.  The switch closes when the magnet is missing.  This provides the opposite action of the special and more expensive unit used by EM.

A Leonelli control on the left handlebar contains the “start” button, the map-select button, and the map indicator LED.  

The controller powers up in Green mode when the start button is pressed momentarily.  There is no neutral.  White mode (less powerful than Green mode) comes after Red mode in the map sequence.  Some of the early bikes were programmed for a  White-Green-Blue-Red sequence.  Mecatecno does customer surveys, and 50% said they had no use for White mode, so maybe that's why they stuck it at the end of the sequence.  Although, I have been told it's great for getting out of a muddy stream.

There is a small guard for the rear disc.  The front disc has a typical guard. 

Although the footpegs are nice, the brackets look pretty poor.  This may explain why Mecatecno is offering the red adjustable ones for an additional $223 USD.

Subframe

I'm not sure what to make of the subframe.  It certainly is unconventional.

My first impression is that it's not very robust.  It appears to be lightweight.  Probably repairable after a crash.

Apparently, this is the improved (strengthened) version of the subframe.

Venting

In addition to the vent near the countershaft sprocket, there is a vent directly into the motor casing.  Both vent lines terminate near the heatsink for the controller.