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is that at cell level or at battery level? and when will that be available outside of a lab? kellys is right now at 267wh/kg at the battery level for their 900wh battery with current battery tech
I'm not holding my breath. Solid state batteries have been about to enter production since the early 2000's. No joke, we were told to expect them within a year or two. Just like graphene, it's a concept with some grounding in material science, but no effective path to a deliverable. I still have faith in human ingenuity, but ss batteries have stomped on my heart too many times.
The number one application for higher density batteries is in things that fly. There's no sign of ss batteries in the field, other than the usual highly suspicious solid state Chinese drone/personal aircraft claims, which typically turn out to be li-ion/li-po power masquerading as ss. I suspect the tech/auto manufacturer's "breakthroughs on the horizon" releases have as much to do with maintaining investment support as anything else.
I assumed the fazua 430wh to 480wh change was the result of going from 18650's to 21700's and dropping a parallel ? It's a pity there's not a smaller version of a 4680. But at the end of the day, it's all packaging tweaks of the existing compounds, with only a little room for refinement to create substantial improvement.
I haven't seen any more info on the kelly's.
I'd not be surprised if they are using 4680 cells, at a lower series count. Which is good for advertised power density, but the lower voltage will make the drive unit inherently less efficient. So that extra power density may not equate to actual ride time. A 36v pack of 4680's would be over 1000wh and weigh over 3.6kg.
afaik carbon housing
What is the main difference I will feel riding a 250W vs 720W motor with similar NMs of torque?
more intelligent people will arrive and explain it better but... your torque/NMs is your ability to accelerate and pull power.
your wattage determines how the engine will handle that torque in terms of top speed as well as elements of durability / overheating if pulling a shit ton of power long term (think boost mode up a steep hill etc)
of course the X factor would be, brands are tuning their bikes to do different things in terms of efficiency as well as durability so you don't blow up the damn bike. THAT SAID... theoretically a brand should be able to safely tune a bike to have a higher top speed or more efficient battery usage with a larger wattage motor. (and probly many other things such as... ability to tune the motor to be more fluid between input, aka mo powa mo betta)
I'm not sure how noticeable these differences are IRL in terms of the whole industry (factoring in how motors are different regardless). But the motor wattage should just allow for an efficient, fluid, and arguably more durable experience. A smaller wattage motor pulling the same nm's of torque will be struggling to handle all the acceleration, the brand will likely try to down tune it to control erratic input, and the bike likely will be paired with a smaller battery. So it will just be less fast and less efficient, while being lighter. (That's the benefit, since otherwise there really wouldn't be one... Lighter.)
An imperfect visualization would just be the difference between a 4 cylinder vs a V6... Trying to do the same pull in both cars, the V6 is gonna handle the torque better (all other design being similar, hence vastly oversimplified)
I think of it more like torque is what helps you get started from a standstill up a steep hill. Watts are what help you have a higher top speed spinning up a fireroad.
Power is the seat tube angle of ebike stats. Pay way more attention to torque.
Thanks for y'alls input. If the torque is exactly same will the motor with 250W not accelerate as fast from 10-20 or will it not be as efficient and use more battery and possible overheat more than the 720W motor? I am trying to understand the difference I might feel while riding. Thx again.
The latter. Gonna eat the battery. Its probly not gonna feel very fluid. And in order to make it feel fluid they will down tune it to be slower. And you will basically have a lower ceiling of speed on any climb where you are not hitting the outright speed limit of the bicycle (20mph).
I'm not sure how tuneable the smaller motors are, whereas I know stuff like the DJI and new Specialized basically fully open up tuning in the app.
Cuz with the smaller motors they know if they let you maximize output as much as possible, you're gonna torch the battery and then complain about range... And you may even torch the motor and then complain about durability lol.
At the end of the day brands are going to tune to optiize the motor so that it lasts long and feels ok-ish to pedal. I hate when ebike motors kick in and out SUPER hard.
To my knowledge it's usually fairly linear in design. Aka, you won't see any high torque low wattage motors or low torque high wattage motors. And if you do, they will just be down tuned around the bottle neck anyway. Kinda like if you build a gaming computer, with the BEST video processor on the market... But then you give it a crap CPU, crap power supply, low RAM, etc. You'll never touch the GPU's abilities with all those bottlenecks.
Ultimately your main concern should be weight of the bike, and how you balance battery range with 'ride feel'. Put annoyingly simple: bigger=better, smaller=worse.
I'm not sure what people consider the diminishing returns to be. I think ~50 pounds is the most ideal. 45-55 is acceptable depending on your bias, 45lbs for ride feel, 55lbs for battery range. And then stuff that is lighter or heavier is usually pretty 'bad' for either bias. ~40 pound ebikes give up way too much range but only feel slightly better to ride. And ~60 pound ebikes don't give you way more range, all while ruining the bike feel and suspension performance.
Kellys are using common 21700 cells but invested alot in the case which is made of carbon.
Rotwild,which has a 250w/kg battery, also did the same with carbon for the case.
There are alot of promises about new cell tech and ss batteries but not alot of actual products available.
One promising company that seems to have a product that works though is :
https://amprius.com/solutions/sicore/#next
Before my levo I rode a mullet converted external battery ebike which reach was way too short for me (somwhere between 430 and 440mm) but it was slack and light. I think even a bit lighter than my levo gen3 S4 with the 500 wh battery and it was more fun to ride in certain situations. Like it felt snappier but with the Levo I can now ride over the front more and I feel more centered in the bike. I wonder how a Levo S3 would feel for me at 5 11
With the weight of an ebike its usually possible to do a few interesting / unusual things. Naturally, being heavier, you can usually feel more stability and generate more traction on a bike that is too small for you. And in terms of that extra weight there may be a few other things to consider, such that upsizing would probly not be a good idea. Although getting the correct size should be fine. But if you were tweener, one would probly lean towards downsizing with the ebike. (To me, with modern numbers, downsizing is the new upsizing... Unless you're so awkwardly tweener you are choosing between like S and M, cough Canyon cough)
But yeah Peter Jamison just had a cool convo with Ryan Burney (wish I knew how to tag his vital name) on youtube here, that mentions these things: https://www.youtube.com/watch?v=idd5IZgxia4
The downsizing thing really hinges around the specifics of the bike.
For example, brands that do not have a consistent f/r ratio due to not adjusting chainstay lengths appropriately between sizes typically have better handling mediums. A long front center with short chainstays requires more shifting of weight when riding, and a shorter wheelbase allows that to happen with less overall effort. Personally, I find bikes with f/r ratios closer to 1.8 can be ridden just as well when sized up, due to a more central riding position and not requiring major weight shifts to weight the front end. I'm kind of between large and xl with most bikes, and go back and forth quite often.
I'll take em as short as I can get. I'm here to fuck around and find out. Big Cahal fan. But I want my chainstays like 420 even with a ~460 reach, AND i want stack height to make it even worse. 600+
And that's why nobody should listen to me for bike advice.
That said, for an ebike, considering its never going to be a playful slopeduro rig anyway... I'll absolutely take a more even ratio, even though... I suppose with the front bias of the weight it's actually not as big an issue? I would just generally argue downsizing is more valid with ebikes than it is normal bikes. And from what I see they almost all have long rear center seemingly due to design need? Who has da balls to make a 420mm chainstay ebike? hmm
That would probably be very difficult to do i think. Just for an example the trek fuel has 436 chainstays. The Fuel + has chainstays just over 440. Chainstays have to be made slightly longer to have space for the motor. Packaging constraints are the big issue there. But imagine a zink vacay in ebike form with a tq motor. That would be a really fun bike
Hah, he reviewed the hd6 recently and likes it. Mostly due to the highly unbalanced ratio afforded by a 510mm reach, 435mm chainstays and 1280 wheelbase. Like you allude to with your desired geo, they go all in on the hd6.
Riding that front end like a unicycle.
I can totally see downsizing being a preference based thing to make the extra e bike mass easier to manipulate Jeff KW style. All depends on use case.
ya i wonder what the shortest FS EMTB has been so far. typically struggle to trust geo chart numbers but...
the DJI druid apparently goes to 430 in s1. norco range apparently 428mm in s1. and the SIght and Fluid versions are doing 432.
pivot shuttle apparently 432 as well. and turbo levo SL does 433 in s1 and 432 in all others including s5? lol
seems the high pivot with growing cs may help in those regards. but the Fluid is a normal drivetrain, as is the shuttle and levo. but that Range is WILDLY short. interesting.
sadly it's not what the market wants so... ain't really gonna happen but it would be a fun one off project if it basically shared a front tri with something else? like some one off chain stays for a Canyon team rider already on the Spectral ONfly. Give it to Braydon he'll go crazy on that thing. dirt jumper ebike!
Replaceable and adjustable rear dropouts FTW
I think that will be the next standard for mountain bikes. Makes so much sense. Make one rear triangle, let the consumer buy dropouts for their desired length. Crestline lets you go from 435 to 460 if you're riding MX. Kavenz, Forbidden, RAAW (on certain models) and others already do it.
It's an awesome feature but only works on VPP style suspension designs. Doesn't work on crablink.
In what way specifically? Transition got creative...
Where did you get the lower guide the one I bought originally didnt work.
That's pretty much a direct copy of forbidden's setup. Who no doubt were inspired by someone else.
Works great, I have a 450, 460, and 470mm chainstay option for my dreadnought v2, as well as 27.5, 29 options. It's fun to experiment, and surprising how it really makes a dramatic difference, one way or the other, on different types of terrain.
ForbiddenBikeCo_DreadnoughtV2_ModularDropoutSwapout.pdf
Ya the 20mm option is SIGNIFICANT. I wonder if they had an understanding of what the limitations were for how long you want to push out that piece. At what point the inset doesn't support the whole thing and it basically becomes a long lever with not a lot of material or whatever. As chunky as it is.
Crestliine was my reference. I can't tell what the range is for the DH bike, bit the new emtb has 25mm total at 5mm increments.
I'm sure there's a structural limitation there at some point, but it's not been an issue with the forbidden setup. They use the same dropouts on their downhill bike. Never heard of a failure. They did have an issue with the retaining bolts being out of spec slightly and causing the dropouts to loosen up over time, that's been corrected.
I run the 470mm/mullet drop outs most of the time on my dreadnought, am 190 pounds, and pretty much a pro when it comes to casing and overshooting the hell out of everything in a bike park. No dramas so far.
You only get 29 and 27.5 drop outs. Cascade won’t make anymore they don’t have the time I’ve asked the question already
Kavenz is high pivot crab, as others mentioned, Forbidden is doing it. Raaw Yalla v2 is also crab. For the money we pay for these overpriced outdoor toys, it seems like it should be standard feature.
Kavenz:
Raaw Yalla v2 dropouts (soon to be on the madonna?):
Here's a chance for your e-bike lurkers to ask all the thorny questions about e-MTB power: https://www.vitalmtb.com/forums/hub/forum-hot-seat-e-mtb-power-discussion. Key employees from Fazua, Specialized, Avinox, and TQ are all standing by to be grilled!
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