New motor: Made in Canada, 2022 Mid-drive system

[scrambler]

Tuesday we find out. 2500 watts is still, well, 2500 watts feeding the back wheel and the current crop of shimano and sram components are not built with that kind of power in mind. Unless you believe there is some kind of reduction gear transmission in the middle that has the abilty to ease that raw power from the motor. If so, you than have to ask, what is the point?

I do not think you understood what was said.
The motor being discussed is a dual drive train. This means on one side the motor has a chain or belt going directly to the rear wheel hub, without going through any gearing derailleur or other.
On the other side, the pedaling cranks go through a separate chain to the rear wheel derailleur or IGH.

This means the motor power never goes through the derailleur or IGH of the pedaling side.

This is what is used on other high-power bikes like LMX, SEM or BoxxBike, so you can have many kW (8kW on BoxxBike) of power on a bike that still has pedal assist and not put any of that power through the pedaling HW.

 

[m@Robertson]

Clarification: the bike still uses bicycle chain on the pedal-power side. The power-train however uses it's own chain, independently. This provides redundancy between the two systems.

OK so that actually tells me quite a lot. My Cyc uses a Kart chain and those are *quite* robust. So much so there really are zero wear issues with the chain, and the chainrings seem to handle themselves pretty well - as in I know of no premature wear stories that don't have some reasonable abuse explanation. My own has been running since 2019 on the same hardware. That drive is capable of being pumped up to I believe 6 kw. Here is a pic of mine close up, not so you can look at the motor, but so you can compare the relative size of the kart chain in the foreground and the SRAM EX1 chain behind it.

So whats the bad news? You will be seeing at least one extra freewheel in this system and likely two. (left front and left rear). Those parts have bearings that wear. Anyone who has followed Cyc's evolution knows they had a lot of growing pains in this regard, BUT they also used their gen 1.0 customers as beta testers and from what we are hearing so far 'this mystery vendor' has done their homework.

I have no concerns about a kart chain per se. Its a good choice. But this style of motor inevitably has more things that can wear out. Not saying this can't be counteracted... after all I say over and over again how my mid drive builds do not show accelerated wear.

The ebike motor market has been stagnant of genuine innovation for years. Looking forward to seeing where this goes. Unlike the motor below a jackshaft completely decouples power delivery from the drivetrain so you can use whatever you please for the human rider.

 

[m@Robertson]

Tuesday we find out. 2500 watts is still, well, 2500 watts feeding the back wheel and the current crop of shimano and sram components are not built with that kind of power in mind. Unless you believe there is some kind of reduction gear transmission in the middle that has the abilty to ease that raw power from the motor. If so, you than have to ask, what is the point?

I kinda skim over the Watt Wagon's forums, and I believe people have had problems with their high powered motors making the rear cassette/derailleur skipping teeth in the high gear positions. Not sure if that ultimately was figured out to be a misaligned drivetrain/chain issue, derailleur adjustment or just too much power going into the drivetrain. But it will be interesting from an armchair engineers position to see what this set up does and addresses.

You can use DT 350 hubs, both the Classic and the Big Ride, with a steel mtb body upgrade, OR get hold of the 350 Hybrid hub meant for ebikes and tandems. This hub costs no more than the standard 350, is beefed up at the flanges and the bearings, has a 24T solid engagement ratchet and lastly includes the steel cassette already installed. I have several and they have no issues with my 2500w Cyc and none with my 1750w BBSHDs. Zero signs of wear visible after a 1300 mile teardown which was pretty impressive.

According to Pushkar the SunRingle hubs he uses are capable of even higher torque tolerance, but the solution to 2500w is the 18T engagement ratchets in the DT ratchet system versus any pawl system other than perhaps what SunRingle is using. So if his bikes had some skipping issues, I'd say as always that its much more likely to be user error, followed by some uncracked code insofar as the next link in the chain (pun intended) is concerned. In this case I would look to cluster construction and chain choice as both of those have to be on point as well.

But... its all been done and its all fine. You just have to build it right with every piece in the puzzle, and then there is a learning curve (list of don'ts) for the rider.

How To Ride a Mid Drive Ebike Without Breaking It

If you can ride a bicycle you already know how to ride a hub drive ebike. Not so a mid drive. Particularly a powerful one that can tear your chain apart. Fear not. The rules are simple.

talesontwowheels.com

This means the motor power never goes through the derailleur or IGH of the pedaling side.

But it DOES mean that it has to go thru the hub. So you have to do things like pay attention to the hub flanges. Your spoke choices. Your spoke count. Even the spoke nipples.

I am having a wheel completely redone now (thanks supply chain shortages!) because my wheel builder did what he thought was a cool thing and used narrow 14mm alloy nipples (in an alternating color) on both sides of the valve stem. Is a nice little spiff that wheelbuilders can use to signify a custom wheelset.

But on a cargo ebike that runs heavy loads up steep hills, you gotta play hardball. One of those DT Alpine (badass) spokes snapped right at the top of the nipple. However none of the brass 16mm nipples nearby did, and in fact the wheel was so strong (SunRingle MTX39) it never even went out of true.

 

[scrambler]

OK so that actually tells me quite a lot. My Cyc uses a Kart chain and those are *quite* robust. So much so there really are zero wear issues with the chain, and the chainrings seem to handle themselves pretty well - as in I know of no premature wear stories that don't have some reasonable abuse explanation. My own has been running since 2019 on the same hardware. That drive is capable of being pumped up to I believe 6 kw. Here is a pic of mine close up, not so you can look at the motor, but so you can compare the relative sign of the kart chain in the foreground and the SRAM EX1 chain behind it.

So whats the bad news? You will be seeing at least one extra freewheel in this system and likely two. (left front and left rear). Those parts have bearings that wear. Anyone who has followed Cyc's evolution knows they had a lot of growing pains in this regard, BUT they also used their gen 1.0 customers as beta testers and from what we are hearing so far 'this mystery vendor' has done their homework.

I have no concerns about a kart chain per se. Its a good choice. But this style of motor inevitably has more things that can wear out. Not saying this can't be counteracted... after all I say over an over again how my mid drive builds do not show accelerated wear.

The ebike motor market has been stagnant of genuine innovation for years. Looking forward to seeing where this goes. Unlike the motor below a jackshaft completely decouples power delivery from the drivetrain so you can use whatever you please for the human rider.

View attachment 114752

Just to be clear, the setup you are showing is not a dual drive train.
The motor still transmits power through the pedaling drive train, which is not what was being discussed about this new motor using supposedly a true dual drive train.

On a side note, the other benefit of the Dual drive train, is the fact that you can actually have regenerative braking, as the motor drivetrain being independent, you can use the motor to slow the bike with regenerative braking.
That said, people like LMX decided to forgo that benefit, and chose to actually add a freewheel on the Motor drivetrain rear sprocket mount, in order to remove the drag the motor creates when you pedal the bike without any motor assist.

 

[scrambler]

He said the motor is not aimed at DIY but full bike integration.
The fact you may be able to retrofit is inside a bike made for the Bafang is more for the bike manufacturer's benefits, alleviating the need to redesign thier frame.

 

[scrambler]

But it DOES mean that it has to go thru the hub. So you have to do things like pay attention to the hub flanges. Your spoke choices. Your spoke count. Even the spoke nipples.

Well, the power ultimately always goes through the hub, but you are right you need a hub and spokes that can take the power.
The BoxxBike uses 12G spokes on the rear wheel.

 

[m@Robertson]

I was thinking something similar to Panasonic MSDU motor.

The XM-D2 comes with Panasonic MSDU motor.

I think we are talking more along these lines. This is an 'independent' chain driven system. Watching the vid, they're using a kart chain as well.

The LMX64, a powerful freeride E-MTB from France

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. ______________________…

www.electricbike.com

 

[AHicks]

Well, the power ultimately always goes through the hub, but you are right you need a hub and spokes that can take the power.
The BoxxBike uses 12G spokes on the rear wheel.

Not that unusual. Even RAD does that....

Dual drive = HEAVY until I see differently.....

 

[m@Robertson]

He said the motor is not aimed at DIY but full bike integration.
The fact you may be able to retrofit is inside a bike made for the Bafang is more for the bike manufacturer's benefits, alleviating the need to redesign thier frame.

I think more importantly it means you don't need to wait around for frame designs to show up that can use a new bolt pattern. It took years for M620 frames to become as readily available as they are now. Bafang should have adhered to some sort of standard to get around that initially... but if it turns out the M620 bolt/frame pattern becomes a standard then thats going to be a big win over the long term for Bafang and for the aftermarket if the standard promulgates.

 

[scrambler]

Dual drive = HEAVY until I see differently.....

Dual drive IS heaviER, but the extra weight is only two extra sprockets and a chain, so not that big.
And if you are pushing 3 to 8kW, your bike frame IS heavier anyway by a larger margin

 

[Deafcat]

100% of motor power is transmitted via #219 racing cart chain, between an alloy steel machined output sprocket, and a 70T 7075 hard anodized rear sprocket.

These components (chain, sprockets, and associated dynamic tensioner) are intended to last the lifespan of the bike.

The rear hub is conventional: We didn't use a custom hub and don't need to. We haven't been able to damage a single hub yet in regular use (we did damage one in Regen R&D tests).

We did manage to stretch some spoke holes/rim area around the spokes pretty good when towing a 1978 Westfalia (about 4500 lbs). But the wheel remained rideable and the rest of drivetrain was fine.

Frame compatibility is Ultra motor bracket, any 197mm fatbike frame with that motor bracket, essentially.

Weight of the bike is not excessive, compared to some Ultra motor models I've ridden.

 

[scrambler]

I think we are talking more along these lines. This is an 'independent' chain driven system. Watching the vid, they're using a kart chain as well.

The LMX64, a powerful freeride E-MTB from France

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. ______________________…

www.electricbike.com

Yes, this is exactly the dual drive train we are speaking off

 

[AHicks]

Dual drive IS heaviER, but the extra weight is only two extra sprockets and a chain, so not that big.
And if you are pushing 3 to 8kW, your bike frame IS heavier anyway by a larger margin

Different purpose/priorities in mind. I rarely need the Ultra's full rated capacity.

 

[Deafcat]

Yep LMX are a good example of Dual Drive, although I find their bikes to be too noisy (primarily a result of their drivetrain specifics).

I'm really picky about the sound of an ebike: It was important to us that the bike isn't noisy, and sounds good in general. I really like how the acoustics turned out so far! The tensioner design we used is absolutely key here.

 

[scrambler]

Different purpose/priorities in mind. I rarely need the Ultra's full rated capacity.

Fair enough.
To each its own

 

[m@Robertson]

Not that unusual. Even RAD does that....

Dual drive = HEAVY until I see differently.....

Yeah but Rad (and many others who use Chinese parts) does it because the spokes they use are cheap and thicker makes up for using better quality materials. I used 12g Sapim Leader spokes *once* on my most recent wheel build on my Bullitt. Never again. Just for starters, a 12g spoke's head is too thick to fit a quality hub. Biggest they go is 13ga. Plus they add weight where none is needed with a proper spoke. So we see higher strength values with a triple-butted DT Alpine (and triple pricing to go with it). Its more sanely priced ebike alternative is the 13g butted DT Champion 2.34. But in this day of shortages, I'm using the 13/14 ga single butted Sapim Strong. They make the 12/13 E-Strong but here again, 12ga is only for cheap Chinese hubs or hub motors and I can't use them. I have had 13/14 Strong spokes last up just fine under a 3kw Cyclone.

I am certain this motor is heavier as a total system (more freewheels, additional chainring, additional chain). But thats a good thing if it reaches its goals. Weight-weenieness belongs to analog cycling. This all sounds to me like a motor system that will be far more adept at utility uses vs. recreational ones. We need something like that in the marketplace, desperately.

 

[scrambler]

Yep LMX are a good example of Dual Drive, although I find their bikes to be too noisy (primarily a result of their drivetrain specifics).

I'm really picky about the sound of an ebike: It was important to us that the bike isn't noisy, and sounds good in general. I really like how the acoustics turned out so far! The tensioner design we used is absolutely key here.

Good to hear, more points to you.
BoxxBike solution was the Concentric Swingarm. It makes the Bike incredibly silent even with 8kW of power.
No need to bring up the drawbacks of concentric arm, they are well known, but frankly of little impact on that type of bike and use

 

[m@Robertson]

Yes, this is exactly the dual drive train we are speaking off

You and I. We're familiar with the topic. But look up and read @Timpo's post, which I was replying to. Its worth putting up as this kind of drivetrain is going to be very new to a lot of people and some background will help get everyone up to speed.

 

[scrambler]

Agreed, and why I mentioned LMX, SEM and BoxxBike as illustrations a few times

 

[Deafcat]

But what would have been IDEAL is a dual drivetrain with integrated 7/9 gears gear box on the pedaling side
Combine a Pinion and a motor in a dual drive train output.

not so much "ideal", as "impossibly complex, expensive, and heavy"

why reinvent the IGH if you're no longer sending motor power through the pedal-side...