Do 12 speeds still make sense for full powered EMTB's?

[cream]

It's real. Canyon, Comencal, Mondraker are showing them tomorrow. CVT, though - not gears.

Most likely it will be an e-CVT, which will use gears and 2 electric motors.

This was presented last year at eurobike:
https://www.pinkbike.com/news/owurus-continuously-variable-motor-gearbox-unit-eurobike-2025.html

I've tested such a thing (e-cvt), I like the engineering behind (while I don't like traditional CVT) but I'm not sure I want that for my eMTB. (which isn't a gravity/DH oriented bike).

 

[RoJo]

It's real. Canyon, Comencal, Mondraker are showing them tomorrow. CVT, though - not gears.
CVT sounds like the last thing you'd ever want in a MTB, at first. But small gas scooters have been using them for decades with great longevity and surely for MTB use they'd discretize the shifting into however many "gears" you want - exactly the topic of this thread! The result would be a smooth, silent shift at full torque every time.

Perhaps "Pinion" and others have been looking at this challenge from the wrong perspective all along - focused on gears instead of the CVTs which have proven so successful in similar-sized powerplants.

View attachment 187333

This thread just became pointless

 

[RustyMTB]

This thread just became pointless

I mean I did say that last night to gales of laughter!

 

[cream]

This thread just became pointless

or gearless

 

[Petrex]

It's real. Canyon, Comencal, Mondraker are showing them tomorrow. CVT, though - not gears.
CVT sounds like the last thing you'd ever want in a MTB, at first. But small gas scooters have been using them for decades with great longevity and surely for MTB use they'd discretize the shifting into however many "gears" you want - exactly the topic of this thread! The result would be a smooth, silent shift at full torque every time.

Perhaps "Pinion" and others have been looking at this challenge from the wrong perspective all along - focused on gears instead of the CVTs which have proven so successful in similar-sized powerplants.

View attachment 187333

Similar image from E-Mountainbike Mag

Not quite the same.
Maybe different generation of renders ?
You're probably right though, yours is not just an AI image.

 

[zizajaun]

And that destroys Shimano chains but not KMC eGlide EPT.

Right.

As you know, I didn't say anything of the sort. I just said the eGlide chains last longer than the Shimano chains (e.g. LG500), in my experience. That shouldn't be surprising given that they are specifically designed for ebikes, cost more, weigh more, and have an anti-corrosion coating. It's no more baffling than the fact that SRAM XO chains last much longer than SRAM GX chains.

 

[zakflip]

Well this is going to kill the thread.

scrub to 3.12 set your own gearing, thank you Avinox.

 

[RustyMTB]

As you know, I didn't say anything of the sort..

The Shimano chains are also pretty crap, sometimes reaching 0.5% wear in just a couple of rides in bad conditions

We know what you said. Doubling down on it is illuminating if nothing else.

 

[billium]

New Avinox MG sounds promising but we won't know for a while....

Efficiency will likely be less - how much will matter.
Cost will likely be non issue when buying a bike in that the extra motor cost will be offset by simpler transmission.
Added weight sounds like a non issue when transmission is (mostly) removed but some people spend large amounts to save few hundred g so again how much weight will be added?
Reliability of any type of CVT is likely to be lower than traditional gears inside the motor -will we notice?
Will lower reliability be offset by not replacing Cassette and Derailleur - possibly.

 

[zizajaun]

We know what you said. Doubling down on it is illuminating if nothing else.

I claimed Shimano chains sometimes wear to 0.5% in a couple rides in bad conditions (where one ride is lapping a bike park for 8 hours with with a high-power motor and the drivetrain caked in mud) and that KMC eGlide chains last much longer. Obviously those conditions "destroy" KMC chains eventually as well, but not as quickly. There is nothing implausible or mysterious about that: some chains are just more durable than others.

 

[steve_sordy]

Caked in mud, lapping the bike park at 3000 W / 200 Nm.

Mud or no mud, a single strand of standard half inch pitch chain is not designed for that duty. It is not surprising that it wore out. You are lucky it didn't snap!

 

[Suns_PSD]

I claimed Shimano chains sometimes wear to 0.5% in a couple rides in bad conditions (where one ride is lapping a bike park for 8 hours with with a high-power motor and the drivetrain caked in mud) and that KMC eGlide chains last much longer. Obviously those conditions "destroy" KMC chains eventually as well, but not as quickly. There is nothing implausible or mysterious about that: some chains are just more durable than others.

I've never heard of a KMC eGlide chain, now you have me curious.

 

[skizzian]

I've never heard of a KMC eGlide chain, now you have me curious.

I've used the KMC E11 EPT E-Bike Chain on a few bikes - not the e-glide!
personally I didn't really notice much of an improvement over the Shimano on the giant e-bike
on MTB's and especially the missus road bike (neither electric) there was maybe an extra month of use (like 8 instead of 7)
I think the coating wears off pretty quick in UK rain and roads - then the wear on the rollers is pretty much the same

 

[irie]

As you know, I didn't say anything of the sort. I just said the eGlide chains last longer than the Shimano chains (e.g. LG500)

You said:

The Shimano chains are also pretty crap, sometimes reaching 0.5% wear in just a couple of rides in bad conditions, but the KMC eGlide EPT lasts ages

 

[RustyIron]

one ride is lapping a bike park for 8 hours with with a high-power motor and the drivetrain caked in mud

Strava or it didn't happen.

 

[zizajaun]

You said:

I did say that, and it is an accurate reflection of my experience with those chains. I'm still not sure what your point is. Are you denying that Shimano chains can wear that much after 10-15 hours' riding caked in mud with up to 200 Nm of torque going through them? Are you denying that the KMC chains last much longer than Shimano? In any case, I'm just reporting my anecdotal experience in non-controlled conditions. Don't get your knickers in a twist.

 

[irie]

I did say that, and it is an accurate reflection of my experience with those chains. I'm still not sure what your point is. Are you denying that Shimano chains can wear that much after 10-15 hours' riding caked in mud with up to 200 Nm of torque going through them? Are you denying that the KMC chains last much longer than Shimano? In any case, I'm just reporting my anecdotal experience in non-controlled conditions. Don't get your knickers in a twist.

When comparing Shimano chain "X" with KMC chain "Y" how much longer would chain "Y" last than chain "X"?

Your choice of chain "X" and chain "Y".

 

[zizajaun]

When comparing Shimano chain "X" with KMC chain "Y" how much longer would chain "Y" last than chain "X"?

Your choice of chain "X" and chain "Y".

I don't know. I'd have to do some kind of controlled testing. For illustration, Zero Friction Cycling's tests found the XO1 Eagle chains lasted about 2.5x as long as the GX Eagle chains, which demonstrates that chain quality (e.g. a hard coating) can have a major impact on longevity. KMC's EPT coating is just for rust protection; the Turbo version apparently uses heat treating to improve durability as well, but I don't know the details, or how exactly it differs from the Shimano chains.

 

[Paul F]

SRAM seems to be sticking with only 12 speeds for their MTB Transmissions - why?
Sure, roadies want more gears to maximize human performance but with higher power motors today I see no benefit and several downsides to 12 speed.


Downsides vs 11 speed

• Thinner chain with less bearing area so will wear out faster
• Thinner cogs with less bearing area so will wear out faster
• more expensive cassette

Upside

• more gears

I have never ever wished I had an extra gear on my 11 speed Whyte E160!
Can anyone truly say they can tell and want slightly closer gear ratios given the downsides?

I have 12 speed and 10 speed eMTB’s. I upgraded the 10 speed to

SRAM seems to be sticking with only 12 speeds for their MTB Transmissions - why?
Sure, roadies want more gears to maximize human performance but with higher power motors today I see no benefit and several downsides to 12 speed.


Downsides vs 11 speed

• Thinner chain with less bearing area so will wear out faster
• Thinner cogs with less bearing area so will wear out faster
• more expensive cassette

Upside

• more gears

I have never ever wished I had an extra gear on my 11 speed Whyte E160!
Can anyone truly say they can tell and want slightly closer gear ratios given the downsides?

I have 12 and 10 speed eMTB’s. I upgraded the 10 speed to 11t to 46t. The 12 speed is 10t to 52t. On very steep rocky climbs having that bigger cog makes a helpful difference. Having the smaller 10t cog is barely noticeable when riding flat out. On balance 10t to 52t 12 speed is slightly better even with 85Nm plus from the motor.

 

[Mankra]

Sure, roadies want more gears to maximize human performance

Not only: I want also on the E-Bike drive my own cadence.

I´m missing, with 12Speed, one gear at my mondraker: With one gear over 25kph the cadence is to high. With the next gear, I´m zu weak, to keep > 25kph (Shut down speed here in Europe).

So, many Gears help, to drive with the best cadence.

Downsides vs 11 speed

If you see only the power of the Motors: Yes, than less gears are enough. But than we can got town to 8 or 9 Speed (btw: I have sold this year an old Bike, with 9-speed. Lovley, how easy the adjustment of the shifting was....).
With my new Avinox Bike I can climp all steep hills with the 3 or 4. gear. Power is enough, also without Turbo or Boost.

I use the first gears only to start in technical Uphills.

I think with the Avinox motor, half my cassette isn't used.

Yes, nearly here the same.

 

[simcapp]

All those moments will be lost, in time, like tears in the rain...

What we saw last week at EUROBIKE will quickly wipe out derailleurs and cassettes, along with all their adjustment and malfunction problems. The world is changing, too quickly.

 

[Mankra]

Quickly... not sure. But it will be the future at middle and high end Bikes.

 

[MISTER HYDE]

12 speeds on an E-MTB don't make sense to me either. That are designed for normal bikes. The gear spacing can work just fine with 10 speeds. A 52 is not necessary with current motors. An 11-13-15-18-21-24-29-34-40-46 cassette would be more than enough for me.

 

[irie]

As said on post #13

With Shimano 10-51 cassette sometimes use the 51t on technical stuff and the 10t when accelerating downhill. But space out the gears in between no probs.

 

[Ndanger]

Interesting that a Tesla is a single speed transmission and goes 0 to 200 mph (model S Plaid)

 

[caper11]

I have a 11sp and a 12sp in the same bike frame and both have the same power motor. The 11sp is a much better bike for hilly terrain it climbs like a billy goat and doesn’t have as wide of a ratio change on gears, it take more gear changes to get any speed.
The 12sp is more suited for faster trails wider gear ratio a gear change make a difference in the speed. With a max speed of 32kmh, both bikes do not see the small cog. I would have to be going downhill with a tail wind to take advantage of the smaller cogs.

 

[irie]

Interesting that a Tesla is a single speed transmission and goes 0 to 200 mph (model S Plaid)

And an F-35 with a single speed transmission goes even quicker!

 

[skizzian]

And an F-35 with a single speed transmission goes even quicker!

 

[irie]

Yebbut, does it comply with the max 25kph pedelec legislation? Might do since it has no electric battery

 

[gregjet]

Been riding MTB's since 1988. Always been concerned with gearing setups especially during racing days. Recently bought an EMTB to ride with some younger friends just so they didn't have to wait for me for too long ( I only have 40% lunbg function).
So gearing became reasonably important.
I mostly ride my analogue and ride that 36x10-51. I also clip in so my power delivery and cadence will be different from the flat pedal brigade.
My Giant ( insert ridiculously long set of words for name) eMTB is lightweight smaller battery carbon frame . It came with 10-52. I ride almost exclusively on eco with the power turned down to 20Nm and the launch about the same level. I quickly discovered that the 10-52 was hardly used for the majority of riding and being a bit of a weight weenie I changed to 10-45 cassette set. We have some extremely steep sections ( ie hard to even walk up them) , but even that is doable with the 45 just by switching the power up to the next level until most of the climb is done.
On the trails though I found that I rarely had to do much gear changing at all, and when I did it would be several gears at a time. Makes me think that ( for my local trails) that an 8 speed with the 10-45 range would do the job perfectly well.
If you consider why we have slowly increased the NUMBER of gears ( as opposed to the range), it is becase humans have a relatively narrow efficient range of rpm at which they are efficient. That is above and below that range we produce less torque. The whole point of the motor is that it extends the area under the torque curve we produce up AND down. That should mean we need less gear overlap, so less gears over the same range.
Because of the way power is delivered from pedalling, flats will need more gear divisions than being clipped in , but still way less than we have with 12, or even 10 speeds.