Front Hub Motor on a Carbon Road Fork, with what mods ?

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Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 30 2015 3:26pm

With the Q100H now being offered in a Front Hub Motor,
How can a Carbon Road Bike Fork be modified to accept the torque ?

The Time has passed to just say it cannot or should not be done, That is backwards thinking,

The Time is , Now , to figure out how to do it .

I have thought about making custom torque arms for each side, and that would go up the fork a few centimeters up each side of the fork, however they would have to be made so as
to not actually touch the sides of the fork, since having something rubbing on carbon in to be avoided.

meaning 2 or close to 2 mm of clearance so that they do not rub, but will not allow the axle to rotate more than 1 or 2 mm.

another idea is to make a whole bottom through axle type of torque arm / sleeve that would slip up onto the fork with padding inside to buffer the vibration from the torque arm/sleeve and the carbon fork,

Who has done either of these ?

Who can design one of these ideas ?
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Drunkskunk » Dec 30 2015 5:14pm

I'm afraid you are trying to turn lead to gold, my friend. The problem is not with the dropouts, it's with the fundamental nature of carbon fiber being a non-homogeneous material. It's exceedingly strong against forces it was designed to support, but weak against forces it wasn't designed to support.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Chalo » Dec 30 2015 5:28pm

ScooterMan101 wrote: How can a Carbon Road Bike Fork be modified to accept the torque ?

The Time has passed to just say it cannot or should not be done, That is backwards thinking,

The Time is , Now , to figure out how to do it .
No problem; just build a new carbon fork with suitable steel dropouts and reinforcements at the torque arm anchor points. That should be easy for someone with your can-do attitude.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 30 2015 6:03pm

Although I do have a can do attitude,
I have no Shop/Tools/ or Experience with working and designing Carbon Fiber Products.

I do not have any contacts in China in order to have someone there make such a fork,
That is Why I am posting this situation here on E.S.

I see at least three different forks that would need to be made in order to match up with different road bikes.
A completely re-designed Carbon Road Fork

1) Classic straight tube 1 1/8 inch steerer with rim brake mounting hole

2) Classic Straight tube 1 1/8 inch steerer with Disc Brake mounts near axle

3 ) Tapered Head Tube 1 1/8 inch top with different bottom sizes ( there are a couple of different different sized bottom bearing races/sizes on road bikes , not just the 1.5 inch like on Mountain Bikes Blame the Companies that make road bikes for that bad decision they should have all used 1.5 inch bottom bearing sizing )
With rim brake mounting hole , and one with Disc Brake mounts

Wonder who else in the world makes / could design and make Carbon 700 c forks ?




Chalo wrote:
ScooterMan101 wrote: How can a Carbon Road Bike Fork be modified to accept the torque ?

The Time has passed to just say it cannot or should not be done, That is backwards thinking,

The Time is , Now , to figure out how to do it .
No problem; just build a new carbon fork with suitable steel dropouts and reinforcements at the torque arm anchor points. That should be easy for someone with your can-do attitude.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Chalo » Dec 30 2015 6:44pm

ScooterMan101 wrote:Wonder who else in the world makes / could design and make Carbon 700 c forks ?
I'm sure Wound Up in Salt Lake City would talk to you about it.

You're talking about a very small volume product for a very small fraction of a specialty market. And you're talking about having different versions. I think production pricing would approach what you'd pay for a one-off custom job.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Punx0r » Dec 30 2015 8:04pm

I reckon by the time you've fashioned a pair of torque-sleeves to match the shape of the carbon forks and properly spread the load to it, you've eliminated any weight advantage of the carbon fork (ignoring the big lump of iron hubmotor you also just added to the axle). So you might as well save yourself the expense, hassle and health insurance of making the carbon fork work and just use an aluminium (or even, gasp, high quality steel!) one with a conventional torque arm(s).

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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 30 2015 8:05pm

If it were to be made here in the U.S. where prices are higher than Chinese, then make it simple by ...

Start out with designing only one fork, 1 1/8 straight steerer, and the Hole for rim brakes and the two posts for disc brakes,

Like suspension forks were made a few years back, many were made to accept V-brakes , and , disc brakes, so that you can use what ever brake you want .
That can be done with the 700c Carbon fork for a hub motor wheel that I am talking about.

Also

I am not sure but there might be a conversion bottom race/bearing set that would allow a straight 1 1/8 inch steerer fork to be put into a frame that is tapered.

So really only 1 or two forks need to be made. and even then It can be designed anywhere and made in China.

I would say though , that I think it best to use an alloy steerer , forget about a few grams savings with a carbon steerer tube, make it strong. the whole fork could be made quite robust, when designing with the hub motor
and disc ready , to begin with ... at least to start off, then later make another one for tapered head tubes.

So really perhaps , only One fork needed .
Chalo wrote:
ScooterMan101 wrote:Wonder who else in the world makes / could design and make Carbon 700 c forks ?
I'm sure Wound Up in Salt Lake City would talk to you about it.

You're talking about a very small volume product for a very small fraction of a specialty market. And you're talking about having different versions. I think production pricing would approach what you'd pay for a one-off custom job.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Chalo » Dec 30 2015 8:31pm

ScooterMan101 wrote:I am not sure but there might be a conversion bottom race/bearing set that would allow a straight 1 1/8 inch steerer fork to be put into a frame that is tapered.
There are adapters for that; I've installed then at work. The easiest one is an extra large fork crown race that emulates the larger 1.5" size.

Image
I would say though , that I think it best to use an alloy steerer , forget about a few grams savings with a carbon steerer tube, make it strong.
You don't want aluminum then; it makes the weakest and most flexible steer tubes, despite being a common material for that use. Steel is the strongest and stiffest, followed by carbon fiber.

If weight isn't a driving concern, steel is a very effective, inexpensive and fault tolerant material for the whole fork. I think most of the potential buyers of a carbon e-bike fork would prefer that it be as light as practically possible. Otherwise, why would you pay more and accept the durability shortcomings of a plastic fork?
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 1:13am

Chalo,

Great to see that an adapter does exist, that one you show is for adapting a 1 1/8" steerer to 1.5"
However
My Bike has a 1 3/8" lower , with the race inside the headset,
HEADSET1-1/8" upper and 1-3/8" lower sealed Cr-Mo cartridge bearings integrated w/ headset, 20mm alloy cone spacer, w/ 20mm of spacers
Mgf. calls it an integrated headset.

Is there an adapter that would allow a 1 1/8" straight steerer tube fork to work with my bike ?


I agree that steel would be best as a steerer tube for working with a front hub motor, I have been around long enough to own some very sweet
riding Cro-Moly Steel Mountain Bikes, back in the day when there were a few Mgf's that made Butted Cro-Moly frame sets that were almost
as sweet to ride as a good quality Titanium Frame MTB.

I have been researching Chinese Carbon frames, and there seems to be some quality control issues on the all carbon forks, a few here in the U.S. have
failed , broken , on the rider. not read of a alloy one doing that.

In regards to someone making a 700c , Disc , and rim brake fork specifically to be strong enough to work with a front hub motor, then you would really have
to find a craftsman that is familiar with steel steerer tubes, and modern Road/Cross/Gravel 700c forks that are also designed for Disc Brakes.

In that case perhaps it would be better to have the steerer made with Aluminium or Carbon and use a good Cro-Moly inner tube . ( A Sleeve )
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Chalo » Dec 31 2015 1:37am

To my knowledge there is no 1-3/8" headset standard; however there is a 1-1/4" headset standard. If that's what you have, you'll need a little sleeve with 30mm inside diameter and 33mm outside diameter, to put over the crown race seat of your fork so a 1-1/4" crown race can be pressed on. That might have to be made for you, but it's a quick and easy job on a lathe.

A little slice of 1-1/4" x .058" wall tubing, slit open to expand a bit, might also do the trick (if it runs pretty close to true thickness). Put the gap on the side of the steer tube, not the front or back.

Here's what you want, with a caveat: this is a part for a Chris King 1-1/4" to 1-1/8" reducing headset, and I don't know offhand whether the bearing in a CK headset is dimensionally compatible with what you have in your frame. It's worth a closer look.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 1:43am

This is what I have : HEADSET1-1/8" upper and 1-3/8" lower sealed Cr-Mo cartridge bearings integrated w/ headset, 20mm alloy cone spacer, w/ 20mm of spacers

For some reason the Mgf. decided to do that odd lower size on many of the road/gravel bikes for a few years.

Not understanding ( Ok now that you show the link to the Chris King page , I see ) the 30mm ID and 33mm OD , but wouldn't it be a little be different anyway , since I have a 1 3/8" lower ?

I could hire a machinist once I understand the correct size.


Chalo wrote:To my knowledge there is no 1-3/8" headset standard; however there is a 1-1/4" headset standard. If that's what you have, you'll need a little sleeve with 30mm inside diameter and 33mm outside diameter, to put over the crown race seat of your fork so a 1-1/4" crown race can be pressed on. That might have to be made for you, but it's a quick and easy job on a lathe.

A little slice of 1-1/4" x .058" wall tubing, slit open to expand a bit, might also do the trick (if it runs pretty close to true thickness). Put the gap on the side of the steer tube, not the front or back.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Chalo » Dec 31 2015 1:47am

Measure the diameter of your existing fork steer tube where the crown race presses on. If it's 33mm, then what you have is a 1-1/4" lower race.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 1:49am

I Know it is a 1 3/8 " , I had a bike shop order me the upper and lower bearings , and they had to source the bottom and top from different sources , they had to get the lower from the Mgf. .

I think the Mgf. finally realized they screwed up and have gone to the 1 1/4 " bottom, but for a few years they made the odd size 1 3/8 " lower.

Edit : I just went to the Mgf's website , to the bike archive ... and the years before mine, and the years after mine they used a straight 1 1/8 " upper and lower,
Looks like I got the only year of frame with the odd size , in my model. No wonder the bike shop had such a hard time sourcing the bottom.

At least it is a Great Bike , Otherwise.


Chalo wrote:Measure the diameter of your existing fork steer tube where the crown race presses on. If it's 33mm, then what you have is a 1-1/4" lower race.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Chalo » Dec 31 2015 2:00am

Since you're dealing with some goofy proprietary stuff, here's something to find out: Does your fork have a removable crown race? If so, it can be removed and adapted with a sleeve to fit on a normal 30mm crown race seat from a 1-1/8" fork. The inside of the sleeve will have to be 30mm, and the outside will be the same diameter as your existing crown race seat.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 2:09am

Mine is integrated . I had to just slide on the bearings. integrated means that the race is in the frame head tube ? Right ?

While you were posting this, I found out that the Mgf. only screwed up for the one year of my bike. before and after they used straight 1 1/8 top and bottom.

I still like the bike it is a great bike regardless, ... but I did remember what a hassle it was for the bike shop to get the part.

So ...

It looks like for me to build / have a Front wheel Drive Road Bike, I will have to go to a different frame.


Chalo wrote:Since you're dealing with some goofy proprietary stuff, here's something to find out: Does your fork have a removable crown race? If so, it can be removed and adapted with a sleeve to fit on a normal 30mm crown race seat from a 1-1/8" fork. The inside of the sleeve will have to be 30mm, and the outside will be the same diameter as your existing crown race seat.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 2:29am

OK, enough about my road bikes problem of an odd size lower bearing size, most people will have standard 1 1/8" steerer tubes.

Now, ... back to the problem that everyone will have with wanting to put the Q100 or Q100H front hub motor on a road bike,

Who is capable of designing / making a light weight , Disc , 700c front fork , to work with the Q100 or Q100H ?
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by dogman dan » Dec 31 2015 8:10am

Likely nobody in the USA. But in china, where they make most of this stuff, you could get a fork made that had built in tabs to attach a torque arm. You need a guy who makes one of a kind frames and forks custom.

It's just gonna cost you ten times what that's worth. If possible, just put a steel fork on your bike. or even an aluminum fork, and use double torque arms. I would think it possible to have a steel fork converted to tapered, by a good professional welder.

FWIW, if you NEVER had a nut work loose, the nut pressure alone would keep a smaller motor running lower power on a carbon fork. It's not that it's so damn likely a broken fork will happen that is the problem. It's what it feels like if it happens while you are riding that sucks. New teeth, or broken collarbones hurt. I did both my collarbones 8 years ago, and they still hurt like hell every winter.

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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Drunkskunk » Dec 31 2015 9:54am

You could have something designed that would be strong enough out of carbon. There is still the problem that carbon is a non-homogeneous material. it can be extremely strong in one direction, and abysmally weak in another. In the case of a fork, they can't survive lateral loading. That means side impacts will snap the legs easily, and loads that put a lateral strain on the legs, such as being pulled forward by a motor, will break them off like an old dead tree branch.

To make it stronger, you would need to rethink fork design, and build up something beefy enough to withstand the side loading as well. Expect that to come out heavy.

Or you could replace your current fork with something like a Cannondale Fatty, or Surly LHT, which weigh in at 950-970 grams, and would be beefy enough to take all the abuse you could give them. Cromoly Steel is the best material for the job anyway. The oddball lower bearing could be fitted with a shim.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Leebolectric » Dec 31 2015 11:07am

buy steel fork, wrap it with CarbonFiber stickers...best of both worlds.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 1:40pm

DogmanDan,

Yes the whole purpose of me starting this thread is to get someone to design a slip on temporary solution , that could be made for right now , or to find out if someone already has ..... until a completely redesigned 700c fork for disc hub motors are available. I did not want to start two threads, as I know the real answer to the current problem is with a redesigned fork just for hub motors.
And there has to be a young smart student in China who is interested in electric bicycles that can design a completely new 700c fork for disc hub motors, that would keep the cost down.

I can see the price being about up to twice as much $ , it does not really need to be more than that , since there is really just more carbon/epoxy that is laid out in more directions , so as to strengthen the side and torque loads .
So really just about 30% or a little more or a little less carbon/epoxy.

A redesign has already been done to the 700c forks that are disc ready, they are ... not , just the same old carbon 700c fork with a couple of attachment holes for the disc , they have in fact been redesigned to withstand the
forces of the disc brake . So redesigning a 700c fork for disc ready hub motors are just another step in the right direction.


DrunkSkunk,

Yes I understand, that is why the eventual redesign , since it is carbon, and the same thing can be done with fiberglass, albeit slightly heaver, you can make it strong in many different different directions, the reason carbon 700c road forks are weak in one direction is to be more comfortable/ forgiving on ruff surfaces. To be able to ride longer and not be so beaten up at the end of your long ride, the Carbon 700c Road forks we see now on road bikes are a compromise between strength and comfort.
In regards to Cannondale's Headshok, I have owned 2 of Cannondale's Mountain Bikes with the Headshok , and I love the advantage of precise steering and having shock absorption as well , so much so that if I could find a Used Cannondale Scalpel Carbon 29er, with the strange looking lefty fork, I would consider it as I think it would make an excellent Rear Hub Motor Conversion . But it is such an expensive bike to begin with , that has not happened so far.
I am now leaning towards getting a Cromoly disc cyclocross fork , until a Carbon one can be designed / made.


Leebolectric,

I was hoping to avoid having to buy a Cromoly fork for a couple of reasons, first I would rather have the carbon one done so as to not have to spend money twice and having one more part sitting in the Closet ,
But also,
I have already bought a Cromoly rigid front fork , about 10 years ago for a Mountain Bike that I had, I wanted to loose weight on the bike, the bike had a cheep suspension fork on it . So I bought this Cromoly Disc 26er fork , and it was so dam stiff that I hated it. it did not have compliance like a road Cromoly fork, or a Carbon Road Fork .
But now it looks like that is the way to go with a front hub motor build, ... until a carbon fork can be designed and built. BTW I don't care about putting a sticker on it, it is not the cool part of carbon, it is the weight factor.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Chalo » Dec 31 2015 1:59pm

ScooterMan101 wrote:I can see the price being about up to twice as much $ , it does not really need to be more than that , since there is really just more carbon/epoxy that is laid out in more directions , so as to strengthen the side and torque loads .
So really just about 30% or a little more or a little less carbon/epoxy.
Economy of scale doesn't work that way. Yes, you could possibly bring such a product in at 2X the cost of a cheap generic carbon fork. But that's only if you could buy and resell an entire container load of them. I probably don't have to tell you that's more forks than there are potential buyers for such forks worldwide.

But who knows? Alibaba probably works miracles from time to time.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 2:08pm

Chalo,

This time it can work, because, there is also a new trend that is just happening with Road Bikes / Gravel Road Bikes / Sportif Road Bike 700c forks, not just the disc brake feature/redesign,
And that is .... Through Axle Road 700c Hub / wheels !
So for the person who is forward thinking enough, the two can be incorporated, the current road carbon 700c disc , and, the through axle forks are a 2nd step up from what you are used to seeing on the classic 700c rim carbon fork !
What I am talking about here is Generation 3 .

With both done at the same time , ( designed for the torque of a hub motor and through axle ) there Will be the need for many containers of such a fork, just like a few years back there were containers of Front suspension Forks for 26inch wheels that had , both , the ability to use v-brakes or disc brakes, there was a big enough market for that that it worked.
the same thing apply's to what I am talking here, you see not just the fork redesigned for Hub motors , redesigned it for Hub motors , and Through Axles !

Look back at this post a year or two from now if you do not see ( at this time ) the significance of what I am saying here.


Chalo wrote:
ScooterMan101 wrote:I can see the price being about up to twice as much $ , it does not really need to be more than that , since there is really just more carbon/epoxy that is laid out in more directions , so as to strengthen the side and torque loads .
So really just about 30% or a little more or a little less carbon/epoxy.
Economy of scale doesn't work that way. Yes, you could possibly bring such a product in at 2X the cost of a cheap generic carbon fork. But that's only if you could buy and resell an entire container load of them. I probably don't have to tell you that's more forks than there are potential buyers for such forks worldwide.

But who knows? Alibaba probably works miracles from time to time.
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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 2:30pm

If anyone does not quite , yet, understand what I am talking about the fork being designed and made for hub motors/disc brakes/ and through axles,

Picture your typical hub motor , front or rear, it has a long axle in order to slip the axle up onto the drop outs. and it has enough threads on the outside of the drop out , in order to use a washer or two and the nut to tighten the wheel onto the bike.

Now picture that hub motor with a the axle that is shortened on both sides,

Here is How would it fit into a though axle fork .

Picture a kind of nut that has a sleeve around it, with the threads on the inside, ( or rather picture a round sleeve with threads on the inside and that is flanged on the outer end where you normally have the quick release now )
your hub slips not into a dropout ... but between the holes in the fork/ or rear triangle, and you take that sleeved nut for both sides and thread them through the fork and onto the axle ,
also instead of having a bolt head , or a quick release one side and nut on the other , have the sleeves/nut made so that you use an Allen Wrench to tighten each side to the fork .

Of course this apply's to one side , the other side the wires from the motor will have be passed through the axle sleeve nut that I am describing.

Edit/Addition , To elaborate a little more on the design , first besides the threads on the inside of the sleeve nuts, there should also be threads on the outside as well , and threads on the fork itself , what you do is thread into the fork and through to the axle of the hub motor's axle.
on one side of the fork you would have it made as to use a allen key to tighten, on the other side where the wires of the hub motor will exit through the fork/axle/ axle sleeved nut. to tighten that end have it machined to use a wrench , thin like the thickness of a pedal wrench , just smaller than 15 mm size.
So in your kit of tools for roadside repairs just a small allen wrench and very thin, small open box wrench is needed, these tools will also aid in less theft of the front wheel.

There you go, the Future, is Here Now, that is as soon as anyone does this.
Last edited by ScooterMan101 on Dec 31 2015 4:01pm, edited 1 time in total.
My first conversion ... Sold

viewtopic.php?f=3&t=71378&p=1077497&hil ... 1#p1077497

It's 2018 already, lets get some real , improved e-bike / e-velomobile / e-motorcycle designs .

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Drunkskunk   100 GW

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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by Drunkskunk » Dec 31 2015 3:58pm

A carbon fork like the On One is 970 grams. The Cromoly Steel Surly Long Haul Trucker fork I mentioned is also 970 grams. And the On One wouldn't be strong enough for a hub motor, while the LHT would be.

Yes, you could design something out of carbon that would work. Very likely it would end up heavier than a steel fork. All that extra mass would make it much stiffer, dramatically impacting the ride. And in the end, you would still have an unacceptable failure mode.

I'm not anti-carbon. I happen to like carbon frames, and plan to build my own someday. But carbon isn't always the best material. Sometimes it's the worst.

So this leads to the question: Why?
What is it about carbon forks that makes you want to preform this alchemy? Turning the worst possible material choice into something workable?


You're through axle idea sounds interesting. Put that would lead to proprietary frame and fork designs. You couldn't just grab any motor and convert any bike, you would need to buy your motor and frame from the same supplier. The idea might get you an A+ in an industrial design class, but real world applications would be limited.
Now if you wanted to make a through axle that could fit any bike with a standard through axle frame, that would possibly have a market. Justin built a few prototypes. There may be some info on them buried on the Ebikes.ca website. He shows one briefly in the documentary on him. sadly, he seems to have moved away from that project, but that's an opportunity for you if you can design one yourself.
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ScooterMan101   1 MW

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Re: Front Hub Motor on a Carbon Road Fork, with what mods ?

Post by ScooterMan101 » Dec 31 2015 4:21pm

DrunkSkunk,

Well I want to have this done with carbon fiber for a few reasons.

First , I have already owned a Cromoly Front fork and it transferred all the road irregularities up into my body. It was No fun riding it. My body was sore.
When I have ridden carbon forks there is, besides the compliance designed/built into it,
there is also absorbed road vibration dampening .

Second, with carbon fiber or even fiberglass for that matter, you can design and make a product with more weaves and more fibers in different directions, so
that you can have a strong product and it will absorb more of the body punishing bits on the road , more than a steel of the same design.

Steel can twist more . and so therefore be long lasting, it has that going for it, it will only not and break , only as long as it is made right.
and even now they are not designed/made specifically for hub motors.

However

I was also thinking about the Through axle part , I just did not post about it at first,

I would much rather have any motor done in a through axle type of way than of the way we have now , which is just nuts that can come loose, because then with the way I describe you do , Not, have a drop out in which the motor can torque itself down and out of .
look at a bike now with through axles , fork or rear triangle, there is no way for the hub motor to torque its way down and out.

You have somewhat of a torque arm already built into the frame, when you design a fork , or rear triangle, that has no drop outs,
That is a big advantage,

You can right now convert a hub motor to work with a through axle bike frameset or frame, or fork,
Just need to cut off some of the threaded axle, each side, being careful not to cut the wires
Then have a machinist make two sleeve/nuts that I describe, and you are good to go.

I would rather have the product available commercially since in my area Machinist's are expensive, very expensive.
And 99% of the time they are too busy to even take on such a small one off work project. At least where I live .
Last edited by ScooterMan101 on Dec 31 2015 4:37pm, edited 3 times in total.
My first conversion ... Sold

viewtopic.php?f=3&t=71378&p=1077497&hil ... 1#p1077497

It's 2018 already, lets get some real , improved e-bike / e-velomobile / e-motorcycle designs .

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