A note on hub motors for hill climbing

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And quality craftsmanship.
Before I bought my first ebike I watched a video of a supposed (mass produced) "monster" bike. 4x26 tires, big motor, "100 mile range", etc.
It was supposed to be a mountain or trail ready type thing.
On the guys first ride the mid drive motor pulled the chain hard enough to break the (I don't know what it's called) connection between the freewheel and the wheel.
The chain and gears would spin but the wheel wouldn't spin with them.
That had to be a long walk home. :whistle:
You point out a consideration we tend to ignore. The mid drive puts its boost through the chain and shifting components whereas the hub turns the wheel directly. Fewer components to overstress.
 
You point out a consideration we tend to ignore. The mid drive puts its boost through the chain and shifting components whereas the hub turns the wheel directly. Fewer components to overstress.
Yes, but they are if anything more critical. If torque arms are not in place on the hub motor's axle, then the frame dropouts will spread or shear clean off, which will literally destroy the frame. Most frames will take so much work to repair its not worth the effort and you can kiss it goodbye.

The use of torque arms (i.e. building smart) eliminates this as an issue, just as riding it smart and building it smart eliminates (completely) excess wear and breakage issues on a mid drive. Without question a mid drive requires a higher level of both rider and builder competence, but the former is easily learned and the latter is a job you only have to do right once, and there are plenty of guides out there to get it right.

The benefit is you get a bike that is potentially the best at nothing but capable of going everywhere a bicycle can go, versus a bike that is simpler, but has performance limits that can be deal-breakers depending on where you live (on flat land or rolling hills this handicap disappears). Trailside chats with other cyclists riding Rad Rovers and Runners, Lectric Xpeditions and even the new Specialized Globe Haul ST (my neighbor has one now) and similar in my home area repeat the same mantra: The thing is gutless going over hills and they have to take the long way to find shallower grades, or walk the bike up the hill.
 
As a forty year cyclist who likes to pedal, the Mahle (ebikemotion) X35+ hub motor did just fine. For those who do not like to pedal your machine, your experience will vary.
a a sunrise ride.jpeg

About 6000' of elevation gain on these 2 climbs. It made Mt Rainier Natl Park enjoyable again by bike, been almost 6yrs. Felt like a 65 yo, again.
a a crystal mt ride.jpeg
 
I'm nearing 40 years of pedaling also, along with nearly 30 years of on & off employment in the bike industry.

I'd say 95% of riders out there would do just fine with hub motor ebikes,
save your hard earned money to enjoy riding your bike rides (stop to enjoy a meal, get some nice comfy saddle, cycling shorts, etc) over drive system that require multiple drivetrain parts & maintenance to operate.

If you have the money to spend thousands more for mid-drive ebike, doesn't necessarily mean that you enjoy riding any more than a hub-drive ebike. Call me cheap, but I rather enjoy riding and spend less money & time maintaining drivetrain parts.

Torque arms required for hub motor?
only if you require significant power output on your ebike, majority (I would say over 80%, even on heavy leaded cargo ebikes) of riders would probably never need it.
 
Torque arms required for hub motor?
only if you require significant power output on your ebike, majority (I would say over 80%, even on heavy leaded cargo ebikes) of riders would probably never need it.
I have personally destroyed a fork with a 750w Bafang fat motor on a bike that was empty and not a loaded cargo bike. Its a mistake to think of power as the determining factor. Its user error. All you have to do is forget to torque everything down after changing a flat tire, and that lapse will be plenty to destroy some very expensive parts. That was my mistake although the cause was a long day of building a bike late into the night, a tired but eager rider and a lapse of concentration.

The $40 you would spend on two torque arms is much easier on your wallet and peace of mind than buying a new frame or fork. Since I learned not to cheap out the hard way, I always err on the side of caution.
 
If it happened to you, must apply to everyone else?
Was your destroyed fork designed to be used with a 750w hub motor, to sustain its power output?

Thousands of hub-motor ebikes get ridden in NYC by delivery workers, 24/7, in all weather..
most, if not all of them have no torque arm on their ebikes..
If their livelihood depend on the operation of their ebikes.. without torque arms, I guess that's good enough for me.
 
If it happened to you, must apply to everyone else?
Was your destroyed fork designed to be used with a 750w hub motor, to sustain its power output?

Thousands of hub-motor ebikes get ridden in NYC by delivery workers, 24/7, in all weather..
most, if not all of them have no torque arm on their ebikes..
If their livelihood depend on the operation of their ebikes.. without torque arms, I guess that's good enough for me.
i spun a hub drive out on an ?espin nero" my friend seemed more than happy to get rid of,after my little crash before Ieven got going ,rode 3 miles stopped tp ask a guy about church repairs,got on the bike hit the throttle a little,bam! a 30 h error came up on the display,finally it dawned on me what had happened,the stator spun out,funny thing is I had my fingers on the nut of the opposite side the day before it seemed tight,it was so tight it was hard to remove, not so on the side I didn't check(about finger tight) my friend is about as hardheaded as I am( even to the point he makes bikes I sold or traded him unridable in a day or two- not blaming him just saying) taking the freewheel off with an impact cut the living heck out of right index finger and my cumulative crashes have resulted in not being able to walk( the walk in clinic guy said ah ha! gout we will x-ray that foot anyway, so it goes,turns out the outer tarsal was splintered( one of the 10 worst pains of my life) don't worry it will heal he sez, finally the redness and swelling is going down(ontop of sprained ankle) so I bought a trike to convert,believe me I am not about speed after pounding the pavement over hill and dale to get my recovery vehicle I hope I have learned something- make sure the axle nuts are tight! wanted to get a "grin" torque arm( out of budget) my friend acts like he would like the espin back, so he might get it after I install a new hubdrive,repaint( to aggravate him) and upgrade some
 
i spun a hub drive out on an ?espin nero" my friend seemed more than happy to get rid of,after my little crash before Ieven got going ,rode 3 miles stopped tp ask a guy about church repairs,got on the bike hit the throttle a little,bam! a 30 h error came up on the display,finally it dawned on me what had happened,the stator spun out,funny thing is I had my fingers on the nut of the opposite side the day before it seemed tight,it was so tight it was hard to remove, not so on the side I didn't check(about finger tight) my friend is about as hardheaded as I am( even to the point he makes bikes I sold or traded him unridable in a day or two- not blaming him just saying) taking the freewheel off with an impact cut the living heck out of right index finger and my cumulative crashes have resulted in not being able to walk( the walk in clinic guy said ah ha! gout we will x-ray that foot anyway, so it goes,turns out the outer tarsal was splintered( one of the 10 worst pains of my life) don't worry it will heal he sez, finally the redness and swelling is going down(ontop of sprained ankle) so I bought a trike to convert,believe me I am not about speed after pounding the pavement over hill and dale to get my recovery vehicle I hope I have learned something- make sure the axle nuts are tight! wanted to get a "grin" torque arm( out of budget) my friend acts like he would like the espin back, so he might get it after I install a new hubdrive,repaint( to aggravate him) and upgrade some
Well heya neighbor, i'm glad you're ok.
Stay Safe!

HP :cool:
 
If it happened to you, must apply to everyone else?
Was your destroyed fork designed to be used with a 750w hub motor, to sustain its power output?
There is no such thing as a fork designed to work with a hub motor. Once again you're stirring the pot with short-sentence nonsense along the lines of the old "Have you stopped beating your wife yet?" word game.

Your "sustained power output" gambit purposefully misses the point and changes the subject simply to create an attack surface for the rest of your invented argument. My point was pretty clear that high power output was not even the issue to be concerned with.

I've stopped even trying to engage in respectful debate with you as its clear you aren't here to help people. You have an axe to grind and you just want to argue.
Thousands of hub-motor ebikes get ridden in NYC by delivery workers, 24/7, in all weather..
most, if not all of them have no torque arm on their ebikes..
If their livelihood depend on the operation of their ebikes.. without torque arms, I guess that's good enough for me.
Fork failures due to a lack of torque arms, or a foolish use of a suspension fork with a motor (that hasn't been neutered to low power so it is not unsafe), are common occurrences widely reported in the DIY ebike community. The causes of such things are also widely known.

This simple image search is tip-of-the-iceberg


Go to Endless Sphere and search for "torque arm" or "front fork failure" and watch what comes up. It is less likely to, but can also happen in the back. $20 for one rear torque arm proofs you against a colossally expensive risk.

If you really were as experienced as you have claimed to be in the past, I'd add 'irresponsible' to my description of your post. You advocate against the use of a known, cheap safety measure that puts people needlessly at risk. Can people get away with it? Sure. Roll the dice. Should you advocate unsafe practices to inexperienced readers asking for help? Thats a question you never ask yourself.
 
There is no such thing as a fork designed to work with a hub motor. Once again you're stirring the pot with short-sentence nonsense along the lines of the old "Have you stopped beating your wife yet?" word game.

Your "sustained power output" gambit purposefully misses the point and changes the subject simply to create an attack surface for the rest of your invented argument. My point was pretty clear that high power output was not even the issue to be concerned with.

I've stopped even trying to engage in respectful debate with you as its clear you aren't here to help people. You have an axe to grind and you just want to argue.

Fork failures due to a lack of torque arms, or a foolish use of a suspension fork with a motor (that hasn't been neutered to low power so it is not unsafe), are common occurrences widely reported in the DIY ebike community. The causes of such things are also widely known.

This simple image search is tip-of-the-iceberg


Go to Endless Sphere and search for "torque arm" or "front fork failure" and watch what comes up. It is less likely to, but can also happen in the back. $20 for one rear torque arm proofs you against a colossally expensive risk.

If you really were as experienced as you have claimed to be in the past, I'd add 'irresponsible' to my description of your post. You advocate against the use of a known, cheap safety measure that puts people needlessly at risk. Can people get away with it? Sure. Roll the dice. Should you advocate unsafe practices to inexperienced readers asking for help? Thats a question you never ask yourself.

I never specify fork mount hub motor, please read more carefully.
If you're stupid enough to mount a high power output hub motor on a fork to propel your heavy cargo bike, likely it's your own fault when it fails.

I don't need to go anywhere to search for evidence to prove your point, find them your self and support your own argument.
You can't provide evidence yourself, then you're just full of BS.

What have I claimed in the past specifically?
What exactly am I being irresponsible of?
Can you please specify?
 
No you are not worth the time. Besides, you know full well the staff deleted most of your argumentative posts right here in this thread.

For a sampling, just scroll up and look at your latest efforts fighting what are essentially inexpensive safety measures that keep people from personal harm and losing their ebike investment.
 
No you are not worth the time. Besides, you know full well the staff deleted most of your argumentative posts right here in this thread.

For a sampling, just scroll up and look at your latest efforts fighting what are essentially inexpensive safety measures that keep people from personal harm and losing their ebike investment.

As if you're worth the time? When you can't even provide evidence to support your own argument.
I know that You seem to be pick on my posts specifically. As if your own posts did not get deleted by admin?
Does your post above contribute anything to the topic of thread?
What personal harm do you refer specifically? what evidence can you provide that someone has been harmed?
What ebike investment are you even talking about?
 
As if you're worth the time? When you can't even provide evidence to support your own argument.
There is no argument other than the one you started. Just because someone says the sky is red, doesn't obligate me to take time out of my day to amass scientific evidence to the contrary. My posts stand on their own merit already. I always try and include examples meant to show a reasonable, prudent individual I am not just some schmuck with a chip on his shoulder running his mouth. I try to never, ever use an argument from authority. If for no other reason than there are so many morons on the internet pretending they know wtf they are talking about.
I know that You seem to be pick on my posts specifically.
I don't. Really. But when I see someone saying demonstrably wrong things - especially considering where we are, a place where people spend real money they may not be able to afford to waste - as a matter of principle I can't let misinformation stand unchallenged. I worry mostly about the people who come into a thread days or likely months afterwards. If they see hogwash go unchallenged they may act on it and suffer accordingly.
As if your own posts did not get deleted by admin?
Pretty much not. Its happened only in the context of back and forth with you, personally and its been a part of a general thread cleanup. In this thread I think it was, as well. A whole conversation was wiped out, and the community was the better for it.
Does your post above contribute anything to the topic of thread?
The one where I recommended an inexpensive fail-safe practice as already described and re-described? I'll let the community decide that.
What personal harm do you refer specifically? what evidence can you provide that someone has been harmed?
The answer to the first question is obvious. It has already been well articulated, and I even gave links that will send you directly to photos of fork failures, and discussions of the problems that come from same. A reasonable individual will easily be able to understand that shearing off fork fropouts and freeing an axle while riding can lead to injury.

Your second one is just more of the same what-aboutist, smokescreen. You are deliberately misrepresenting the content of Post #46. Although.. I guess I am the one who was harmed and that was what the post was all about - providing that evidence of the consequences of a simple mistake I made - that others should be able to see they can easily make themselves. All this horses**t you have slung since then is just you being a negative influence on the community. Again.
What ebike investment are you even talking about?
When someone buys a bike, it is no less thn a thousand dollars, generally. Often a lot more than that. That investment. Giving poor advice with holes in it introduces risks that the person who relied on what you said will lose the hard earned money they quite possibly can't afford to lose via a broken bike, or a bike that can't do what they need. In the current case, no torque arms result in permanently broken parts like forks and bicycle frames. Someone who cares about the people they are advising will be mindful of the fact they may cause someone to spend hard earned money - or lose it - from their words. I try to only advocate 100% solutions, and if its not 100% I'll advise what the risks are going in a cheaper or less-capable direction. What matters is people are given the ability to make an informed decision. Not one polluted by a personal agenda.
 
There is no argument other than the one you started. Just because someone says the sky is red, doesn't obligate me to take time out of my day to amass scientific evidence to the contrary. My posts stand on their own merit already. I always try and include examples meant to show a reasonable, prudent individual I am not just some schmuck with a chip on his shoulder running his mouth. I try to never, ever use an argument from authority. If for no other reason than there are so many morons on the internet pretending they know wtf they are talking about.
There is no argument because you can't offer any evident that support your posts, other than your personal experience, your personal mistake.
Which do not apply to general or majority of ebike community.
I don't. Really. But when I see someone saying demonstrably wrong things - especially considering where we are, a place where people spend real money they may not be able to afford to waste - as a matter of principle I can't let misinformation stand unchallenged. I worry mostly about the people who come into a thread days or likely months afterwards. If they see hogwash go unchallenged they may act on it and suffer accordingly.
Wrong things according to you doesn't represent wrong things for everyone else.
Pretty much not. Its happened only in the context of back and forth with you, personally and its been a part of a general thread cleanup. In this thread I think it was, as well. A whole conversation was wiped out, and the community was the better for it.
Pretty much not doesn't equate to zero post deleted.
The one where I recommended an inexpensive fail-safe practice as already described and re-described? I'll let the community decide that.
What fork failure have you seen on cheap ebikes with a hub motor specifically? are there numerous incidents that you can provide data on?
Do rear hub-motored ebike not represent majority of cheap ebikes sold or used?
under What community? does this community represent the majority of ebike users?
The answer to the first question is obvious. It has already been well articulated, and I even gave links that will send you directly to photos of fork failures, and discussions of the problems that come from same. A reasonable individual will easily be able to understand that shearing off fork fropouts and freeing an axle while riding can lead to injury.
Articulate your own personal experience and mistake do not represent majority of ebike riders nor general ebike users.
Personal experience are just anacdodal, not representation of majority, nor ebike community in general.
Your second one is just more of the same what-aboutist, smokescreen. You are deliberately misrepresenting the content of Post #46. Although.. I guess I am the one who was harmed and that was what the post was all about - providing that evidence of the consequences of a simple mistake I made - that others should be able to see they can easily make themselves. All this horses**t you have slung since then is just you being a negative influence on the community. Again.
You offer zero evidence that cheap ebike riders have actual accidents when their hub-motor is used without torque arm, just you assume that since you have had a failure yourself. Reasonable person would call than anecdotal and not a representation of general users.
You think reality as what-aboutist, smoke screen, when in fact cheap ebike workers log way more saddle time than most recreational riders.

When someone buys a bike, it is no less thn a thousand dollars, generally. Often a lot more than that. That investment. Giving poor advice with holes in it introduces risks that the person who relied on what you said will lose the hard earned money they quite possibly can't afford to lose via a broken bike, or a bike that can't do what they need. In the current case, no torque arms result in permanently broken parts like forks and bicycle frames. Someone who cares about the people they are advising will be mindful of the fact they may cause someone to spend hard earned money - or lose it - from their words. I try to only advocate 100% solutions, and if its not 100% I'll advise what the risks are going in a cheaper or less-capable direction. What matters is people are given the ability to make an informed decision. Not one polluted by a personal agenda.
Yet here we are again, you've managed to contribute nothing but another string of posts that need admin to delete.
You're out of touch with majority of folks that actually ride their cheap ebikes for long hours or even a living.
Your assumption & your spin on safety or investment for front hub motor torque arm requirement does not apply to majority of cheap ebike users with rear hub motor.
Your 100% solution do not apply to majority of cheap ebike users, therefore invalid for the majority of ebike community.

Inform decision are made when people are given information that apply to them, not absolute 100% solution that do not apply.
Your personal experience and mistake do represent your personal agenda of advocating for 100% solution that do not apply to the general cheap ebike community.
 
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