Greyborg RC

[Lucky_Hoodlum]

Hal,


In the end, I would love to stock his frames and he could stock my drives. I can also supply him with White Brother's forks as I am a dealer for them now.

Have you discussed or thought of possibly becoming partners in a business? Recumpence the USA agent and HAL the European agent for the products.

I like this new frame HAL may i ask which software you use to design your works of art ? Likelyhood of me using it is very low im sure im relatively new to PCs so this engineering type applications i figure will be steep learning curve.

Look forward to updates.

 

[MitchJi]

Hi,

If you want to pedal in conjunction with driving through the cranks you need to get the RPM at the crank down to roughly 80-120 rpm. At that speed chain noise isn't an issue (any more than for pedaling) so you can use belts for the reduction before you hit the cranks. So there is nothing inherent in a crank drive that precludes the use of belts to get a quiet system.

Okay, that's good to know. I was under the impression that the only way to drive through the cranks were to have some special free-wheel for the crank or to have it spinning at chop-your-leg-off velocities. The former costs money and possible design time, whereas the latter well... possibly could hurt in so many ways.

IMO you should have a free-wheel even though it isn't spinning at high rpm. Aside from general riding comfort, even at 120 RPM, if your foot slips off the pedals or you have a problem, before you hit the kill switch, do you really want your leg whacked at 120 RPM driven by a 2 or 3kw motor driven through 10:1 or 20:1 reduction?

Doesn't require anything beyond off-the-shelf parts. Just use an off-the-shelf IPS tandem crank (I'd recommend replacing the FW with an off-the-shelf White FW from Sickbikes):
http://sickbikeparts.com/catalog/product_info.php?cPath=21&products_id=62

 

[recumpence]

Hal,


In the end, I would love to stock his frames and he could stock my drives. I can also supply him with White Brother's forks as I am a dealer for them now.

Have you discussed or thought of possibly becoming partners in a business? Recumpence the USA agent and HAL the European agent for the products.


KiM

Hal mentioned this himself in a PM.

I am open to anything he wants to do, including making his own drive.

It's all good.

Matt

 

[HAL9000v2.0]

I am open to anything he wants to do, including making his own drive.

It's all good.

+1

only replace drive with frame


The frame with assimilated reduction will come eventualy...

 

[spinningmagnets]

I am unfamiliar with the laws in Europe where HAL is, but...

I think it is brilliant that since both of you are developing a high-end product, you are co-ordinating so that they can be easily used together. But I humbly add a caution. When Burt Rutan developed the "long-EZ" home-built plane he only sold kits, and never offered ready-built planes. He was very open about wanting to avoid lawsuits brought by the wives of drunk pilots.

I would not sell these together, but I would advertise that they are both guaranteed to bolt right up, with an added label indicating they are legally for "off-road" use only. Buyers will still use them however they want, and will understand it is only to prevent spurious lawsuits. Sometimes people sue with absolutely no justification, hoping to be paid a small settlement to "just go away".

Just a thought...

 

[johnrobholmes]

Even if a drive was "integrated" into a frame, i would want it to be easily removable for service. Much like a motor and tranny comes out of a motorcycle or car.

 

[swbluto]

An assimilated/integrated drive would be nice, eventually, but any kind of panel/flat area say on the side of the swing arm to mount an RC motor would tremendously assist in just getting over the first and seemingly greatest obstacle, attaching the motor to the bike.

 

[flyinmonkie]

I think the ultimate would be a frame with a bracket for a motor and a bracket or brackets for batteries. Incorporated into the frame would be bosses to press sealed bearings in and run a jack shaft, or several jack shafts to attach pulleys or sprockets to for gear reductions. The motor and size of pulleys and sprockets would be up to the end user and easily changeable. The bearings would also be easily replaceable. Several styles of frames could be developed, MTB, cruiser, chopper, road, hard tail, full sus. From the sounds of things, the road is being laid.

FM

 

[johnrobholmes]

Unless the motor has a large diameter it will need some sort of reduction, and it makes sense to have the motor bolt to the reduction instead of the frame.

Surely it can be built with motor attached to frame, with other mounts for the reduction units. I wouldn't want one like this personally, at least at this point in the game. Geometries and layouts should be played with more. It may be a cheaper way for the total package however, as the jackshaft bearing tube(s) could simply be welded into the frame instead of machined from billet.

 

[swbluto]

Unless the motor has a large diameter it will need some sort of reduction, and it makes sense to have the motor bolt to the reduction instead of the frame.

Surely it can be built with motor attached to frame, with other mounts for the reduction units. I wouldn't want one like this personally, at least at this point in the game. Geometries and layouts should be played with more. It may be a cheaper way for the total package however, as the jackshaft bearing tube(s) could simply be welded into the frame instead of machined from billet.

Even if it were made that way so that the motor could attach to the frame and it'd be possible to mount reduction units as needed(Maybe you could mount the bearings tube, instead of welding, so that the bearings tube could be optional if you want more than one stage reduction?), you could *still* get matt's drive and play with it how you'd please, so your geometries and layout options are not really restricted. Not unless you had something more configurable in mind...

And, it's possible to attach the pulley to the motor and a much larger pulley to the wheel, or sprockets if you prefer to the hub, to get the single-stage reduction needed. My scooter seems to do just excellently with 8 inch wheels on a gear ratio of 4 with a 200 kV motor. For a 26 inch wheel, that corresponds to a gear ratio of about 12. With a 100 kV motor, that'd correspond to a gear ratio of 6. That's certainly feasible! And it just seems so astonishingly simple in a way that I just can't ignore the possibility.

 

[flyinmonkie]

John,

I agree there needs to be a lot of research and testing done on geometries and week points, etc. Also the ability to tighten or adjust tensions on chains and belts would be difficult if the bearing tubes were incorporated into the frame. But, it would be clean and stylish as well as looking complete and like a production product instead of a bike with stuff bolted to it. I feel it is a long way off yet, but I feel it is the direction we are going. If people here can take quality name brand bikes and turn them into a quality electric bike that is fun and usable, I imagine it won't take the major bike manufactures long to start producing quality electric bikes themselves with incorporated electric componentry.

FM

 

[HAL9000v2.0]

Ok here is Model RC-naked, or developer pack, rear caliper holder is still missing.

 

[HAL9000v2.0]

design variations...

 

[12p3phPMDC]

Nice models HAL...

I like the triangulation with the tubing...and with the shock load paths going into the Y leg..
appears to be very strong indeed.

Do you build them using 4130 chromoly or cold rold steel?

You could certainly package everything nicely in those boxes/spaces.

 

[HAL9000v2.0]

Nice models HAL...

I like the triangulation with the tubing...and with the shock load paths going into the Y leg..
appears to be very strong indeed.

Do you build them using 4130 chromoly or cold rold steel?

You could certainly package everything nicely in those boxes/spaces.

I use carbon steel 1212 and heat treatment after welding.

 

[JS Tyro]

I see angulation, but not triangulation. That will not necessarily be a light-weight solution. However, it may be adequate. The three open parts of the forward frame are all relying on flexure in the tubing for strength/stiffness. Carrying the load from the shock forward like a mixte frame design or a modern mountain frame with the top tube and seat stay in line would be potentially better.

 

[HAL9000v2.0]

I see angulation, but not triangulation. That will not necessarily be a light-weight solution. However, it may be adequate. The three open parts of the forward frame are all relying on flexure in the tubing for strength/stiffness. Carrying the load from the shock forward like a mixte frame design or a modern mountain frame with the top tube and seat stay in line would be potentially better.

That is correct but then the front "space" have to be lowered or divided in half which is good for small cells not for 10Ah or bigger.

 

[JS Tyro]

Which may be a more important feature.

As I said, it may not be the lightest, but it may be adequate. Given so many factors that can come into play in the design, it's possible that the overall weight will not be much different than an "optimal" design, given that the overall weight is governed by the weight of batteries, motor, etc. Those of us that have played with real design issues in structures know that sometimes excessive attention to one detail may be time wasted when so many factors are important.

My point was just to address the comment on triangulation. I guess many non-engineer/physicist types would not get the point of the triangle concept. Triangle really means triangle - three sides closed.

Esthetically, it's an interesting design - it has something going for it.

 

[12p3phPMDC]

JStyro

I agree that it isn't perfect triangles and that I realized what I had said after the fact, but probably much stronger than the plates that hold the large batteries in the earlier iterations.

Yes, with the angles in the frame, you are more prone to flexing forces on the tubes
and that it may not be as stiff as possible.

Care to share your optimized designs with us?

 

[swbluto]

Well, I'll leave this post as an ending note. I was hoping there'd be a frame eventually developed that had some kind of integrated motor mount and thought this might have been an opportunity to share the idea, but now I'll just sit back and let things flow. If something comes to development in 3 months or so, that'd be great(!) and I may definitely consider purchasing, otherwise I'll be looking to my own improvisations (I may just get a moped frame).

 

[JS Tyro]

Care to share your optimized designs with us?

For what? Ice resistance of an offshore structure? I don't have anything concerning bikes if that's what you want.

These forums are fairly technical. Don't be surprised or offended just because someone corrects your terminology. Proper terminology leads to better communication and clearer dissemination of ideas.

 

[12p3phPMDC]

My apologies for being sensitive...

But, it is probably much a much stiffer frame with the Y vs. the Battery plates, no?

 

[JS Tyro]

If you can get the cover plates to tie into the frame structurally, you could get a very stiff and strong frame. That would be like a stressed skin design. However, that could be more trouble than it's worth. The hassle of getting the batteries in and out would be a PITA. OTOH, if the batteries stay inside for months at a time and are charged while in the bike, it could be worthwhile. At that point, you could literally get rid of the frame and just use the skin for the entire design.

 

[12p3phPMDC]

Stressed skin would be very strong indeed.

A single plate bonded or pinned to the frame would
give you access to everything on one side.

No access worries. And if you wanted to, you
could add covers to the exposed stuff.

 

[Dan Frederiksen]

guy told me you've tested the alleged A123 cells on ebay and concluded they were fake because their resistance was too high. are you aware that the specified resistance is mostly 1kHz ac impedance and not DC resistance?
in other words are you certain they are fake? have you compared to a known real cell like from dewalt packs?