First custom carbon fork special made for hub motors

[lnanek]

Don't ebikes with carbon forks tend to have much thicker ones than the one in the OP? E.g. Luna's:

23t32t-min-1.jpg (74.33 KiB) Viewed 283 times

And that's not even a front hub model. So all that thickness is just to handle the speed from the middrive. I'd expect a front hub carbon fork to be even more reinforced.

[Tony01]

Front hubs are a bad choice.

[tomjasz]

Front hubs are a bad choice.

That’s just silly. They have their place. My front GD and a DD are veritabl3 tractors and have thousands of grocery hauling miles on them. I have 4 other mid drive bikes but for simple builds a front drive motor is a great option for many. I really like the regen braking on my DD front trailer pulling “tractor”. Powerful and effective braking.

[tomjasz]

Don't ebikes with carbon forks tend to have much thicker ones than the one in the OP? E.g. Luna's:
23t32t-min-1.jpg

And that's not even a front hub model. So all that thickness is just to handle the speed from the middrive. I'd expect a front hub carbon fork to be even more reinforced.

That is one fugly ride.

[Tony01]

Front hubs are a bad choice.

That’s just silly. They have their place. My front GD and a DD are veritabl3 tractors and have thousands of grocery hauling miles on them. I have 4 other mid drive bikes but for simple builds a front drive motor is a great option for many. I really like the regen braking on my DD front trailer pulling “tractor”. Powerful and effective braking.

That’s cool, my car has TENS of thousands of miles hauling groceries and even it is RWD. So?

Yeah the variable regen on my rear hub was extremely effective as well, seen peaks of nearly 10kw regen. Soooo?

Front hubs are a bad choice for many reasons. The best reason is if you only buy very cheap kits and motors and want to run a few of them rather than a single strong mid or rear hub.

[ZeroEm]

Front hubs are useful, Trikes, Snow, Sand, etc.....

[Tony01]

Front hubs are useful, Trikes, Snow, Sand, etc.....

They’re only useful if you are going very slow. In an ideal maximum acceleration situation there would be no weight on the front tire. Nobody is really riding in the sand all the way to work or hauling their groceries in the sand. On snow you have limited traction and a front hub steals some of it that you really need for steering. The only time they’re useful is if you have a few underpowered setups and want to increase your load capacity by adding a front hub to an existing rear hub setup.

But, if I was running a trailer I’d run rear hub and trailer hub(s), and setup a delay on the trailer for throttle and delay on the bike rear hub for regen.

[lnanek]

That is one fugly ride.

Interestingly, it seems like the goal of that carbon fork was to provide some amount of suspension without any moving parts:

Full Composite suspension fork for fat bikes.
Zero maintenance fork by removing all "moving parts", virtually removing upkeep.
Military spec S2 glass fiber.
60mm of travel with progressive spring rate

https://lunacycle.com/lauf-carbonara-carbon-fat-fork/

Maybe that's why it looks so weird. Irrelevant to me anyway since if I have a motor assisting me I see no point in paying extra for lightweight carbon parts. They are welcome on my human-power-only bikes, though.

[ZeroEm]

by Tony01 » Dec 18 2022 8:24am

ZeroEm wrote: ↑Dec 18 2022 8:11am
Front hubs are useful, Trikes, Snow, Sand, etc.....

They’re only useful if you are going very slow. In an ideal maximum acceleration situation there would be no weight on the front tire. Nobody is really riding in the sand all the way to work or hauling their groceries in the sand. On snow you have limited traction and a front hub steals some of it that you really need for steering. The only time they’re useful is if you have a few underpowered setups and want to increase your load capacity by adding a front hub to an existing rear hub setup.

But, if I was running a trailer I’d run rear hub and trailer hub(s), and setup a delay on the trailer for throttle and delay on the bike rear hub for regen.

From a high power two wheel perspective your right. Staying in line with the thread.

[avandalen]

What is the expected purchase price of this item? Hundreds of dollars or more?
[/quote]

Just about $150 or so.

[avandalen]

I would avoid putting in the "idiot washer" hole, because it takes out material that's under high tensile stress when the axle is trying to pry the slot open.

Also I'd orient the slot facing forward, so reaction forces from the disc brake aren't in the same direction as the slot opening.

And if increase the width of the material around the corners of the axle slot. Have a look at open end wrenches for well iterated designs that do the same kind of job.

>>>> That's a CPSC requirement for bikes, not forks. Lawyer lips aren't the only way to fulfill that requirement; they're just the most annoying way that's hardest to get rid of.

So it isn't mandarory?

Not for forks. It's also at odds with what you're trying to accomplish in terms of compatibility with a range of hub motors.

If you make both sides with identical IS disc tabs, then the right side can be used to anchor a torque arm (which you can also make and sell). Or silly people can put together dual disc setups.

Even if you don't do that, you should incorporate some mounting point that can be used for a torque arm. Best if it's also able to serve another purpose, for instance a fender mount, rack mount, or disc tab.

Thank you for your advice
The strength becomes the same as with wrenches and everything will be tested and oversized
there will also be a mounting point for an extra torque arm

[avandalen]

I think, that all hub motors for front forks have axle diameters of 12mm with a flat side of 10mm (also 1000W motors) else they will not fit to any fork.

I don't know that all the front motors have only 12mm "tall" axles...I'd have to research that.

I have a Leaf front motor with a 14mm axle. I have a Crystalyte front motor with a 14mm axle.

It's easy enough to provide a fork tip that will work equally well with 12x10, 14x10, and 16x10mm axles.

My carbon fork is for hub-motors with a 12mm axle, for very large hub-motors, weight saving no longer makes sense.

[avandalen]

Front hubs are a bad choice.

Not for e-bike motors up to 250W
Look here: https://www.avdweb.nl/solar-bike/hub-mo ... ight-ebike
and here https://www.avdweb.nl/solar-bike/hub-mo ... ive-vs-hub

[avandalen]

On this video you can see what I mean with a lightweight ebike, this is my Maxun One solar bike.

This is what my carbon front fork is meant for.

[avandalen]

This is another demonstration of my (lightweight) Maxun One solar bike

[E-HP]

This is another demonstration of my (lightweight) Maxun One solar bike

Well that's great video. Short, but clearly demonstrates a proof of concept. In order to study it more carefully, you can turn the speed down in the YouTube settings to 0.25X. I detect some sinusoidal oscillations at around the 5 to 6 second mark. Maybe due to the flexing.

[avandalen]

This is another demonstration of my (lightweight) Maxun One solar bike

Well that's great video. Short, but clearly demonstrates a proof of concept. In order to study it more carefully, you can turn the speed down in the YouTube settings to 0.25X. I detect some sinusoidal oscillations at around the 5 to 6 second mark. Maybe due to the flexing.

Yes, the panels are flexible and therefore indescribably strong. More than 10,000 km driven without any problems.