Aluminium E-Bike MTB frame production

[Timma2500]

My thoughts exactly. Having motorbike performance when no one is looking is one thing, but try coasting down a footpath with the engine off on a dirt bike and see if it doesn't get the cops attention.

Yep. The extra storage space would be handy for batteries etc, but yeah, you'd be on a limited time frame before the cops spot ya...

I think on a custom frame 'torque plates' rather than arms are the way to go. If you could make an oversized flat Al drop out area with a deep slot you could then easily bolt a steel plate to it. It wouldn't even have to be a 14x10mm axle hole - just a 10mm slot in the steel plate that bolts up the opposite way to the drop out would do. (something like these that I made but up the other way)

Using those plates with no actual torque arm, would that place extra stress on the dropout and its fixing points to the seatstay and chainstay? I think they are a nifty idea but would i have to beef up the chainstay and seatstay to dropout points with strong gussets if used on their own to help the dropout cope with all that force?
Don't mind if i need to if it helps keep strength up :wink:

I agree your integrated RC drive is very cool and stealth but unless you're planning to offer them practically 'turn key' I think alot of people with lesser skills will have trouble getting it all up and running. If you're going to buy the frames in bulk you definitely want to cater to the hub motor or 'I want a frame with integrated battery space' crowd. As far as building frames from scratch goes, it'd pretty much be worth your while to buy those little dirt jumper frames for <$100 to cut up for all the relevant parts wouldn't it ? (heat tube, bottom bracket etc )

Keep the ideas comin boys!
I'm not going to offer the gearbox i've used just for cost reasons - the shaft i could get CNC'd but the housing and large pulley also require machining and would have to be done by hand and thats where the problem is. My machinist charges around $100/hr so the cost would soon balloon out quite a bit by the time each housing and belt pulley are put in the lathe's chuck, clocked up then machined. If people really want to use the same gearbox as i and i get enough requests, then maybe i will look into doing it but it wouldn't be cheap! The frame will be setup so this can also be used later down the track anyway. With frame parts, buying the individual parts it seems is reasonably priced - headtubes and bottom brackets can be had for about $10USD each, pretty reasonable i thought! And saves alot of time cutting/grinding parts.

not to knock hub motors, they have their place, but there is not as much value you can add to a frame designated for hub-motor (ergo lower price bracket).

Thats right. All i can offer them is battery space, somewhere to bolt their controllers and stronger dropouts. That would probably address all their needs unless a hubmotor user can come up with anything else they'd want in a frame


Paul

 

[Hyena]

Using those plates with no actual torque arm, would that place extra stress on the dropout and its fixing points to the seatstay and chainstay? I think they are a nifty idea but would i have to beef up the chainstay and seatstay to dropout points with strong gussets if used on their own to help the dropout cope with all that force?
Don't mind if i need to if it helps keep strength up :wink:

It certainly wouldn't hurt, I haven't had any problem with them but my Norco Ryde being a dirt jumper already had those and the head tube heavily reinforced (which your brand x doesn't )
http://img23.imageshack.us/img23/131/norco2.jpg

Considering all the other customisation you're doing it'd be a worthwhile mod to any frame I'd think. It'll add minimal weight, only a few extra minutes of time to weld in and is an noteworthy feature of beefiness

 

[Timma2500]

Very true, the Brand X has good 8mm dropouts but no reinforcing to the chain and seat stays like your Ryde. Yeah they'd be easy to add to the dropouts.
Cool, another feature added to the list!

and is an noteworthy feature of beefiness

Haha, well put.

Cheers Hyena!


Paul

 

[monster]

erm how can you make an ebike thats 24kg with 4-5kw? thats got to be bumcus. i have frames that are heavier than 24kg! if you stick 5kw on a 10kg frame it wont last long. plus you need batteries and motor. even if you use lipo and RC motors and Al frames your range is going to suc and it will eat batteries!

 

[Miles]

i have frames that are heavier than 24kg!

You have a bicycle frame that weighs more than 24 kg?

 

[johnrobholmes]

5kw with a 24kg bike is totally possible. My LeToy build is 5kw and doesn't weigh more than 28 kilos with motorcycle wheels on it. Drop those down to bicycle wheels and it would shed 5 kilos fast.

 

[etard]

erm how can you make an ebike thats 24kg with 4-5kw? thats got to be bumcus. i have frames that are heavier than 24kg! if you stick 5kw on a 10kg frame it wont last long. plus you need batteries and motor. even if you use lipo and RC motors and Al frames your range is going to suc and it will eat batteries!

I think you have grossly misjudged the progression of ebikes my man, check out any and all of Recumpence builds you will find featherwieght and monster power in the same setups. I would argue that a 2 kg frame can be designed to withstand 5kw, but it's the components that are the weak link in application.

 

[Mark_A_W]

Thats right. All i can offer them is battery space, somewhere to bolt their controllers and stronger dropouts. That would probably address all their needs unless a hubmotor user can come up with anything else they'd want in a frame


Paul

- Removable dropouts, closed around the axle, really chunky. (Most hubmotor axles are a Double D, M14 x 10 flat. Although my Nine C was M12 x 10 flat.)
When you remove the wheel to fix a flat, you remove the dropouts from the frame.

- Space for batteries and maybe mounting points for a box.

- Controller mounts would be nice, but controllers vary so much...

 

[Jeremy Harris]

erm how can you make an ebike thats 24kg with 4-5kw? thats got to be bumcus. i have frames that are heavier than 24kg! if you stick 5kw on a 10kg frame it wont last long. plus you need batteries and motor. even if you use lipo and RC motors and Al frames your range is going to suc and it will eat batteries!

Weight really has sod all to do with stiffness and strength. My hobby has been designing aircraft, where weight is critical, but so is stiffness and strength. I could build a 4130 steel tube aircraft fuselage that weighs around 24kg; making a massively strong bike frame that's a quarter of that weight would be easy, even using off-the-shelf chrome moly tubing. Switching to something as strong as steel, but lighter, like a high-strength alloy, would probably knock another 10% off the weight, although stiffness might suffer (steel is pretty good on the weight/stiffness front). Best of all would be to make the frame from carbon or graphite composite, as this would be lighter than alloy and stiffer than steel.

Making an alloy frame with large sections will get around the inherently poor stiffness of an alloy frame (compared to steel of the same section), so this idea to build in big battery/motor boxes makes a great deal of sense. It should give a significant strength benefit as well, as the material in the frame is being used more efficiently than if the frame were made of smaller diameter tubing.

Jeremy

 

[12p3phPMDC]

Timma,

Best of luck with the Al, what you have done is truly exceptional!

But I have to say that steel is much more forgiving when it comes to welding and toughness IMO.

I look forward to JRH frames and the Al stuff that you come up with!

 

[BiGH]

Hey i hope this works out too. I prefer hub motors. its a personal preference. i welcome more options in custom e-bike frames.

This has to be the best looking frame i've seen that wasn't designed for a hub motor

I just hope there's enough room for lots batteries. and mounts for a strong rack.

Will you be putting all cables and wires through the frame?

 

[Mark_A_W]

Paul

If you are after a donor full suspension frame, I have one kicking around. 7005.

It's detailed here:
http://endless-sphere.com/forums/viewtopic.php?f=3&t=3996&hilit=mongoose


I had the same idea you did basically, except you actually did it.


You are welcome to it.


Mark

 

[Timma2500]

erm how can you make an ebike thats 24kg with 4-5kw?

Too easy! The weight breakdown - Original 2009 Norco Empire 5 - 15kg, Truerc 44.4v 10ah lipo brick - 2.4kg, Astro 8150 - 1.3kg, gearbox - 1.3kg, aluminium insert - 3kg, esc, throttlizer, odds n sods - 1kg. Granted it will get some gussets and powdercoating so add another kilo for them for when they get done.

I would argue that a 2 kg frame can be designed to withstand 5kw, but it's the components that are the weak link in application.

Thats it. I don't expect any problems from this frame but if they arise, i will figure out why, beef-cake it up as required and learn for the next ones. As for the bicycle drivetrain, haha i know its guna wear much quicker than normal and i'm ok with that.

- Removable dropouts, closed around the axle, really chunky. (Most hubmotor axles are a Double D, M14 x 10 flat. Although my Nine C was M12 x 10 flat.)
When you remove the wheel to fix a flat, you remove the dropouts from the frame.

Ok cool, have you heard of many other odd-ball size axles beside the M12 x 10?
Cool yeah i'd be interested in the Mongoose frame - how much would you like for it?

- Space for batteries and maybe mounting points for a box.

- Controller mounts would be nice, but controllers vary so much...

Hmm that they do... so do batteries too! :?

Making an alloy frame with large sections will get around the inherently poor stiffness of an alloy frame (compared to steel of the same section), so this idea to build in big battery/motor boxes makes a great deal of sense

Correct and thats what it did. With an added bonus of being 1 large mofo of a heat sink for the Astro too :wink:

Best of luck with the Al, what you have done is truly exceptional!

I look forward to JRH frames and the Al stuff that you come up with!

Cheers! Yeah i'm looking forward to JRH's creations too and Matts's bright yellow tyre punisher and seeing AJ's cruiser painted up, and Rodgahs 1st build and and.... there are so many awsome builds going on at the moment its hard to keep track of em all. Plus i suspect a few people might be hiding some secret designs (frames maybe *cough* :wink: ) for the time being.

I just hope there's enough room for lots batteries. and mounts for a strong rack.

Trouble is everyone uses different size batteries - my 44.4v 10ah fits in nicely in the Norco but any larger would be a struggle. So the these frames will have extendable sides for the battery compartment for larger size batts. The rack i havn't really thought about but if i can i'll try to leave some tabs for one to mount to.
Hey i like your avatar - is that a XXXX or VB he's drinkin? :lol:



Paul

 

[Mark_A_W]

No you can have it.

Cost of posting it is all.


I'd love to see it cut to bits and rebuilt, better than it was before

 

[Timma2500]

Awsome, thankyou Mark!

I could mod it and send it back to you once the inserts are cnc'd if you like?


Paul

 

[Hyena]

Score!
Mark have you still got the QR disc front wheel ? I'm looking for one for my Norco to bolt up my new hydros to.

 

[Mark_A_W]

Awsome, thankyou Mark!

I could mod it and send it back to you once the inserts are cnc'd if you like?


Paul

Of course I'd like that (who wouldn't), but it's not really my motive.


It is for you to play with and see what works and what doesn't, without killing something you paid $500 for. If it dies, it dies. I'm not using it, I have a Kona Dawg dually frame to build up as a pedal bike already, and ithe Mongoose already has two weld repairs.


If it ends up usable at the end, and you don't need it anymore, I'm happy to pay return shipping and reimburse you for the postage to you But don't feel obligated in any way.


Send me a PM, and I'll post it over. I'm guessing it will be somewhere between $20 and $40 to send it.

 

[Mark_A_W]

Score!
Mark have you still got the QR disc front wheel ? I'm looking for one for my Norco to bolt up my new hydros to.

Nup, it's frame + seatpost only for Paul.


The rest of the bits have been used in various bikes already.

 

[Mark_A_W]

Oh, try Rotorburn forums Hyena.

The front wheel on my DH Team came from there. Perfect match to the rear wheel rim, I was stoked.

 

[Timma2500]

Of course I'd like that (who wouldn't), but it's not really my motive.

No worries, we'll sort something out.

Send me a PM, and I'll post it over. I'm guessing it will be somewhere between $20 and $40 to send it.

Will do. I've gotta run now but will shoot you a pm a 'lil later today.

Oh, try Rotorburn forums Hyena.

Hell yeah, good local source for 2nd hand mtb gear.

Oh and i thought about my gearing again, i lied, i forgot i re-geared the Norco for only 65-70kph based on 85% of no load rpm as apposed to 85-90kph i was originally guna go with...

And 2 new Hyperion 1210i chargers are on the way, re-ordered another as a spare while their only $85USD each. So hopefully a full charge isn't too far away yay!!!!


Paul

 

[Mark_A_W]

Paul

I got the frame out of my second shed.

Comes with a seatpost/clamp, and an original fox float shock.

If you want it, PM me your address.

Cheers

Mark

 

[MitchJi]

Hi Paul,

A better way (IMO) would be the ability to connect to an intermediate shaft on a frame like the Brooklyn Machine Works racelink (http://www.brooklynmachineworks.com/):

Yep and D sounds like he's chasing something similar. If you are in no immediate rush, leave it with me. If i can incorparate this into my 100% design, even as another version, i will do so

Paul

Great news! A jackshaft with a fixed sprocket to the rear hub and 2 FW's, one for the chain connected to the crank and one for the chain connected to the motor would be an excellent configuration IMO.

In comparison with the Dual Splined FW's on the SRAM Dual Drive (or 9 speed free hub) both systems have the following advantages:

• 
  Dual FW's on the SRAM and on the jackshaft prevents backdriving the crank chain and the motor chain
  
  Not necessary to gear down to crank speed and back up to wheel speed
  
  Gears in a Geared Rear Hub available for both pedaling and the motor
  
  Possibility of using multiple chainrings or a Schlumpf for pedal gear changes independent of the motor gearing

The jackshaft configuration would have the big advantage that it could be used with all geared hubs or all derailleur freehubs with all derailleur gears available for both motor and pedaling.

The jackshaft configuration has the big disadvantage that setting it up on most frames (particularly FS frames) is a PITA.

A custom FS frame with this feature would be sweet.

 

[es2150]

I hope something happens in regards to frame mounting batterys in just about any configuration. As long as it's 48volts and hopefully there is a kona/turner type design available. Good stuff and would love to ditch my backpack. Only thing I am wondering is I hated the weight of the battery on rack and wondering if the additional weight in the center would make the bike feel tankish or if it's distributed and well suspended and of coarse well powered then great? I just remember how many times I have eliminated weight from bike and put on my body to make bike feel more nimble. I guess the only other bikes out there in production are the currie and optibike as far as bikes with batts integrated right?
All I know is if you build it I am interested in trying a well balanced fs frame?

 

[AussieJester]

I guess the only other bikes out there in production are the currie and optibike as far as bikes with batts integrated right?

The A2B also carries its batteries within the frames tubing.

KiM

 

[Kraeuterbutter]

hmm..
some postings before, the discussion about
RC-Motors vs. hub-motors

you can even combine it, so for offroad you have your light wheels with no motor int he wheels, but motor on the frame
nevertheless no noice because hub-motor..
and when you go offroad no hits directly to the motor, his axel.. he has not to carry your weight but only his own, ..

here an example:

http://www.pedelec-forum.de/forum/attachment.php?attachmentid=4945&d=1265832554

the ring with the holes for the spokes was removed, so you maybe not see at first that it is a hub-motor

the motor spins with ~150rpm-170rpm under load, so only a 2:1 reduction is nesseccary
the motor hase no classic gears inside but steel-wheels, so the gearing is noiceless
when driving you realy only here the chaine a little bit, nothing from the motor

http://www.pedelec-forum.de/forum/attachment.php?attachmentid=4947&d=1265832811
the crank is a Shimano LX which was modded with an freewheeldrive

http://www.pedelec-forum.de/forum/attachment.php?attachmentid=4955&d=1265879833
from design the motor is waterproof, dirtproof, so nothing has to be done on that

for battery a 2.0kg light 36V 10,5Ah LithiumIon within a driking-bottle:

http://www.pedelec-forum.de/forum/attachment.php?attachmentid=5203&d=1268338347


or this bike:

http://www.pedelec-forum.de/forum/attachment.php?attachmentid=5331&d=1268952839

or - a complete custom made Frame with batteries inside (!) with included hubmotor:
the noisless hubmotor, made lighter without housing (and so only 1,7kg weight), no classic plentary gears but steel-wheels, so silent

http://www.pedelec-forum.de/forum/attachment.php?attachmentid=5116&d=1267794088


and this included in the frame, as well as the battery

http://www.pedelec-forum.de/forum/attachment.php?attachmentid=5117&d=1267794162

http://www.pedelec-forum.de/forum/attachment.php?attachmentid=5118&d=1267794216


all this bikes are very very silent
of course: european, LEGAL style, so no 2kw or 3kw or 4k or 5kw or ....
only "normal" power, "normal" currents
and bikes which start at 12kg weight (INCLUDING motor and the battery !)