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Premium Member
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Discussion Starter · #1 ·
Since i currently dont have a bike (yet),
I use my time planing and thinking out ideas
and designs for my future streetfighter project.
That's part of why im on here too,
so that i can gather as much tips, ideas,
and inspiration as possible until i can start modifying myself.
The other night while i was trying to sleep
(Allways getting idea's when i should sleep),
i got this idea after seeing some harley's
and the Tron Legacy bike without any hubs in their wheels.
And i thought it would be cool to do this on a naked bike/streetfighter
build without having a giant chain going around the entire outside of the rim
(like on the harley's i've seen with this modification)
Or having the entire assembly hidden behind huge side panels....
So i drew it up and I've redone the design a couple of times in my head,
before i drew it up on paint...
(cant remember shit from class when i was supposed to learn autocad)
So i was wodering if anyone could help me get this into autocad
or some other 3d program. or even tell me if it has any possibility of working :)

Here are the drawing i made :


Edit: Oh man i somehow managed to write one of the info boxes in norwegian...
it should say: sprockets on the axles inside of the rim x4

If there is anything you are wondering about just ask,
cause my drawing skills may not be enough for ounderstanding this...
If anyone could share their thought or draw skills i would apreciate it :)

Btw the piece holding everything in place welds on to where the swingarm splits to go on each side of the wheel.
 

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Discussion Starter · #4 ·
I've always been curious as to how these work. I'd love to see one on a fighter. Tired of the chopped guys hogging that shit.
Word! thats kinda why i wanna do it :)
never seen it before :)

How they do it:

Many of the bikes just have giant bearings inside the wheel,
witch is mounted on the frame,
while a chain is wrapped around a sprocket around the rim edge making it go forward.
But that wouldn't work on a fighter without any side plates,
since we need to have our feet straight down,
and then in the harms way for such a contraption.

Theres also something similar with small taps around the rim
witch is connected to a shaft like a gear ... but again the harley's with this feature
got no rear suspension. think that would be a pain in the ass on a fighter :p

The other type is a motor spinning the rubber on the wheel itself ....
know there's some electric bikes out there with that solution.
dont think it would work any good on a petrol bike though ...

So i hope someone could help me draw this so i can test it in theory
with some kind of physics emulator or something :)
 
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watches you sleep.
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Saw one on one of those gay chopper shows. Dude said it had a ten thousand dollar bearing in it
That was Billy Lane. I JUST watched that clip earlier on youtube hahaha. Yeah shits expensive Im sure. Ive also read that theyre not that safe or reliable and thats why theyre not done much. I could totally see how one of those could fucking blow apart if the tolerances are just a micron off.
 

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sickboy
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That was Billy Lane.
That fuck ass is still in prison right? Till 2015 or somthn it was supposed to be.

For those that dont know, he was sentenced to 6 years in prison and 3 years probation in 2009 for manslaughter after he got wasted and decided to drive and ended up killing a motorcyclist.
 

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Discussion Starter · #9 ·

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Old, bold rider
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Hubless wheels are wonderful from a style point of view, but extremely complex from an engineering point of view. To wit: the wheel must be sufficiently supported to withstand all loads while riding, not just acceleration and braking (linear to the direction of travel), but also laterally (right angle to the direction of travel), and a whole bunch of load vectors that have to be considered. Add to that the loads from the drive and brake.

Using a single bearing is one way to do it, but finding a bearing with a 15" OD that doesn't weigh in the neighborhood of 30 pounds or more, can support side loads, and doesn't cost a small fortune will be a major problem. An alternative is to use a goodly number of small ball bearings supported in a beefy carrier and riding in a pair of grooves circumfrential to the wheel rim.

The next problem is drive. A sprocket fitted to the rim would have to be at least 85 teeth, meaning the final ratio with a 19 tooth countershaft would be 4.43:1, roughly doubling the RPM for a given speed -- topping out around 80 MPH. Great for pulling wheelies, but for day to day riding not so good. An internal gear drive is a better solution, but the ratio is such that you would end up in the same boat gearing wise.

A quick take on a gear driven drive:
Hubless concept 1.jpg
The bearings (in green) have to support the wheel around it's full diameter, though the majority of the bearings will have to be where the loads are highest -- at the bottom and front of the wheel. The bearings bear against a pair of tracks securely fixed to the rim, and the 330 tooth driven gear attaches to center of the same track. The drive pinion and its three bearings are supported in the bearing carrier frame which also serves as the attachment to the swingarm. I haven't bothered to draft that up yet, but it is relatively simple. In order to get a final drive ratio that will give a decent cruise RPM it will be necessary to use a jackshaft concentric to the swingarm pivot that will give sufficient room for the drive sprockets from the engine to the jackshaft (roughly 19:15) and a second set of sprockets to the pinion shaft (roughly 45:15), which will give an acceptable cruise RPM.

One other thing to consider is the rear brake. Obviously it would be nearly impossible to attach it to the wheel, but a simple solution woud be to mount it to either the countershaft or the jackshaft.

Anyway, that's my take on it.

Rob
 

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Stealing again from the chopper world, but wouldn't a friction drive prove to be somewhat simple yet effective? It could accelerate and decelerate the wheel so that both sides of the hub is free of clutter. Just my $0.02.

Later, Doug
 

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Discussion Starter · #12 ·
Hubless wheels are wonderful from a style point of view, but extremely complex from an engineering point of view. To wit: the wheel must be sufficiently supported to withstand all loads while riding, not just acceleration and braking (linear to the direction of travel), but also laterally (right angle to the direction of travel), and a whole bunch of load vectors that have to be considered. Add to that the loads from the drive and brake.

Using a single bearing is one way to do it, but finding a bearing with a 15" OD that doesn't weigh in the neighborhood of 30 pounds or more, can support side loads, and doesn't cost a small fortune will be a major problem. An alternative is to use a goodly number of small ball bearings supported in a beefy carrier and riding in a pair of grooves circumfrential to the wheel rim.

The next problem is drive. A sprocket fitted to the rim would have to be at least 85 teeth, meaning the final ratio with a 19 tooth countershaft would be 4.43:1, roughly doubling the RPM for a given speed -- topping out around 80 MPH. Great for pulling wheelies, but for day to day riding not so good. An internal gear drive is a better solution, but the ratio is such that you would end up in the same boat gearing wise.

A quick take on a gear driven drive:
View attachment 31418
The bearings (in green) have to support the wheel around it's full diameter, though the majority of the bearings will have to be where the loads are highest -- at the bottom and front of the wheel. The bearings bear against a pair of tracks securely fixed to the rim, and the 330 tooth driven gear attaches to center of the same track. The drive pinion and its three bearings are supported in the bearing carrier frame which also serves as the attachment to the swingarm. I haven't bothered to draft that up yet, but it is relatively simple. In order to get a final drive ratio that will give a decent cruise RPM it will be necessary to use a jackshaft concentric to the swingarm pivot that will give sufficient room for the drive sprockets from the engine to the jackshaft (roughly 19:15) and a second set of sprockets to the pinion shaft (roughly 45:15), which will give an acceptable cruise RPM.

One other thing to consider is the rear brake. Obviously it would be nearly impossible to attach it to the wheel, but a simple solution woud be to mount it to either the countershaft or the jackshaft.

Anyway, that's my take on it.

Rob
Thank you for a detailed and good answer. So if im getting this right i will have problems maintaining a good cruise speed with my setup idea because the gear ratio will be messed up? Did you look at my bad ass paint drawing? Or are you now talking bout the harley setup? :)

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Old, bold rider
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Thank you for a detailed and good answer. So if im getting this right i will have problems maintaining a good cruise speed with my setup idea because the gear ratio will be messed up? Did you look at my bad ass paint drawing? Or are you now talking bout the harley setup? :)

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Either. In order to get an acceptable final drive ratio the sprockets inside the wheel in your design (or any internal drive hubless setup) will have to be ... let's see ... ((I.D. of the inside of the rim x Pi / the chain pitch) / the desired final drive ratio) x the chain pitch /Pi = the diameter of the drive sprockets. It's not as bad as it looks. ((15 x 3.14 / 0.5) / 2.75) x 0.5 / 3.14) = 5.4545". A bit outsized for the "hubless" look, but will give an acceptable cruise.

On the other hand it occurred to me that there is another way to do it: maglev. Using neodymium magnets arranged in two rings inside the wheel rim with all north polarities facing in (the rotor), and two rings in the stationary hub with north polarities facing out (the stator) brought together with a maximum gap of 0.0075" between the rotor and stator magnets it will produce a very effective pair of tapered magnetic bearings. From my calculations it would take ~ 3 to 4.5 tonnes of force to bring the stator halves together when assembling onto the rotor. Plenty of support for even a very heavy motorcycle.

Then, of course, you still have to drive it somehow. Simple: a very large diameter brushless electric motor with the rotor consisting of a series of round magnets mounted to an aluminum disc attached to the rim and the drive coils wound on "C" shaped cores mounted to the stator. Replacing the transmission with a 200KW generator used to power the drive circuitry (standard integrated circuits available from any electronics supplier) will do the trick. Essentially it becomes a CVT (Continuously Variable Transmission) controlled by logic circuitry connected to the throttle. Another feature: the drive motor can also be used as a rear brake with enough power to lock the wheel.

BTW: 200KW = 286 horsepower. Plenty of margin there.

Here's the wheel -- it will weigh ~ 20 pounds. Not bad considering a conventional setup would weigh about twice that.
Hublesss wheel maglev concept 1.jpg
The rotor bearing magnets (blue) are arranged in a tapered form to support all load vectors, and the motor magnets are in the center. The stator bearing magnets are shown in red.

This is fun!!!

Rob
 

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0.o i didn't do it
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That sounds like a do able concept for some of the electric bikes out now. So what would you do for the front wheel if the above is a rear/drive wheel?? Im interested to see how the designing works out over all..very interesting

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