ebike frame

[liveforphysics]

I just want to add, Maxwell has always been a proven good seller and vendor who has hooked up a lot of ES members, and always delivered.

I'm sure he will make a great product and deliver it.

Aluminum is just a personal niggly of mine.

[slayer]

Well if it would move the sales Luke i would say why not but i think the design is what kills i don t know if Max designer could work with something like this more of a dowhhill and a swing arm that accept the shocks we have for bikes not those of scooter

at the bottom would be similar to the first build but not panier a full sheet covering and on top another panier in v that shape the top of that first panier or some kind of shelves adjustable for the diffent batteries we all have...

and if i understand correctly Luke ...the cro molly is easy to mod and you can weld on that frame wich a lot of guys here love to do ...maybe include your rear rack in the back (the first one)

[bigmoose]

Absolutely great treatise on Aluminum and CrMo fracture toughness and crack propagation on the last page. You couldn't get a better write up from one of our aerospace companies!

PS: The ol' big guy (not nicked bigMoose for nothing) made a recumbent from 1" emt conduit and roadside (trash day) bike bits. Rode that bike for 4 or 5 years and never broke a weld or the conduit. emt has to be the cheapest, krud steel in the world. I sure stress tested it!

[maxwell65]

hi all,

sorry i was not able to respond in some time,,,just to quickly address the 6061 7075 issue,,,for this frame it may be a whole other ball game i will post more news about what material we will use in the coming days,,,all will be done to make sure this frame is done right,no question about that. must hurry off right now but i will respond to all in the coming days.

[Green Machine]

I had a question regarding the chromo vs aluminum question....

Isnt a comparable chromo frame over twice as heavy as aluminum, or are you able to compensate enough with thinner tubing etc to make comparable weights?

What sounds like a big advantage of chromo for guys on this group other than strength is you are able to weld to it and make modifications to it....guys on this group love to tinker and some even know how to weld.

[bongoboy]

Isnt a comparable chromo frame over twice as heavy as aluminum, or are you able to compensate enough with thinner tubing etc to make comparable weights?

Yes from memory about 2.3x heavier but about the same ratio in tensile strength.

What sounds like a big advantage of chromo for guys on this group other than strength is you are able to weld to it and make modifications to it....guys on this group love to tinker and some even know how to weld.

Yes you can tinker around with a 4130 alloy steel frame and probably do so without any heat treatment like a aluminum frame. But it would be advisable to either get a professional welder or person with experience to advise you about precautions to take before and after welding and also to select the correct filler rod and welding parameters (or if you are confident you could research this on the internet). Especially if you are somehow modifying a high-performance (very light weight) frame and still intend to use it in high stress situations.

Or to clarify if you were using a 4130 steel frame that was designed to use as a road bike and wanted to add some welded tabs to the main longitudinal tubes (not the joins) for mounting a battery box or something like that and still use it for road use then I would imagine that would be fine. If you had a BMX, 29er or other off-road frame and say wanted to weld on a torque plate to the dropout and still take the bike off-road I'd say you would seriously want to get that checked out and or done professionally in the first place.

[slayer]

this would be another little idea and would look more like a bicycle

ebike2.jpg (71.45 KiB) Viewed 664 times

[panurge]

Hi guys

I can report my experience in structural materials, they are my field of interest/work...

- Al Alloy 7075 can't be welded: true, but I would add "fusion Welded" to this sentence, for my trellis frames I use only 7075 for plates, but there is no welding....when I start my builds with trellis 7075 was a way to go Ergal without the weld issues.....now we are working with an Italian research department for the use of some friction welded 7075 parts, this kind of welding technology is really awesome....but until now can be cheap and easy only for linear welded parts like plates or flat parts...perpendicular pipe friction weldings are until now near impossible/super expensive.
but we will see in the near future. Until now my Alu welded parts are all 7020 (direct welded or with 5350), that's is a good compromise for me, and work better than 6061 series in my experience)...

- Is true, nothing compare the cromoly expected life if it can be protected from Ox...maybe only Ti alloy but we will see in future years when some Ti part reach the actual age of the oldest cromoly parts . But I concur, the race for Al frames in the lasts years is crazy,....tons of cromoly pipes abandoned in industrial areas....here you can buy them for ridiculous prices... and if you have not in mind Light for races and if you plan to self weld parts, make not sense to not go cromoly.

- About thickness of pipes, I actually use in my new DH and DIRT ALU welded frames, really monsters 7020 tubes, but machined as hexagonal in the 80% of the length ( not near weldings ) this is also a good compromise you take the original thickness at the edges with a good weigh gain...

- Ti is in fact the best actually for me, it has characteristics near special steel, but without special treatment that's beautiful for me....it has awesome look, it's light.... the issues are Price and flexibility (for frames) that's the reason because I use structural Carbon Fiber tubes glued with Ti welded triangulations in The Ti Frames... Ti also need skills and devices to be welded....

Hope this is helpful...

Jules

[bongoboy]

- Al Alloy 7075 can't be welded: true, but I would add "fusion Welded" to this sentence

Hi Jules,

I did read an article that 7075 could be resistance welded to Al 6xxx but it didn't expand on this point so it could have been a variation of seam or spot welding sheet or some other type of fusion like you say. Good to know though thanks.

B

[panurge]

- Al Alloy 7075 can't be welded: true, but I would add "fusion Welded" to this sentence

Hi Jules,

I did read an article that 7075 could be resistance welded to Al 6xxx but it didn't expand on this point so it could have been a variation of seam or spot welding sheet or some other type of fusion like you say. Good to know though thanks.

B

I'm experimenting with 7075 to 7075 friction stir welded parts, it's not fusion weld and it's not between different alloy series, i concur with LFP 7075 to 6xxx or even 7075 fusion welded parts in general are a fake or cracking certainty

Anyway I don't want to pollute maxwell65's thread anymore, I think his final result will be more an E-moped than an E-bike though....in this light maybe final look can be Ok.....for sure an xxxtra-wide range EV

jules

[gblast123]

check out this design... some elements are worth emulating.

http://www.stealthelectricbikesusa.com/ ... omber.html

David

[heathyoung]

Or the website from the country where they are actually made, not just resold...

http://www.stealthelectricbikes.com.au/

[Willow]

...Prototype it! - it's gotta be done. You can CAD model, and ruminate about materials all you want.... but there is no substitute for a physical, working model to refine the design and decision making process. Build it by hand, fit it out with electronics and batteries and ride it!

Prove your product.

[Lenk42602]

takes alot of knuckle bustin' and sweatin' to build something, let alone something that performs as intended....

[maxwell65]

JUST A NOTE TO SAY i just posted the latest pics today (Aug 15 2011) and i think we have a real winner here,all specs will be posted in the coming days and at this point i hope more people will want to place their deposits based on this newest design,,,place comments please,,,as we are soon ready to go into production,,,THIS IS GOING TO HAPPEN FOLKS,WE NEED THIS BIKE!

MAX

[liveforphysics]

Max- I noticed you're still saying 7075 and 6061 for materials... Just to clarify, this company does know that 7075 can not be welded right?

[o00scorpion00o]

Hi Max,

I like it, however I noticed the omission of suspension, please clarify that?

I couldn't afford it now anyway, but a full suspension frame is a must for me!

I can't wait to see one built!

Mark

[chroot]

HI- You gave up the full suspension already? I required have full suspension ebike please.

[deVries]

JUST A NOTE TO SAY i just posted the latest pics today (Aug 15 2011) and i think we have a real winner here,all specs will be posted in the coming days and at this point i hope more people will want to place their deposits based on this newest design,,,place comments please,,,as we are soon ready to go into production,,,THIS IS GOING TO HAPPEN FOLKS,WE NEED THIS BIKE!

MAX

For a non-rear sus bike this is a decent design on paper. I like it.

However, I still want to know the dimension specs. I can't order unless I know:

Wheelbase w/Standard Design Fork Choice(s) Noted & any rake.

Chainstay length or Distance between Bottom Bracket & Rear Dropout (center to center).

Standover Height with typical wheels/tires choice(s).

Seat-tube & Head-tube Angles.

Please note Materials choices.

Design suggestion: Do the Disk Brake Mounts so these can accept cheap/powerful Moped Brakes, which should have much better braking power & cost less to service. It might be a good idea to use wider & stronger rims too. Also, maybe moped or light weight scooter/motorcycle rims. I would prefer to use 50-85mm wide rims.

Please make sure the rear rack can seat a 200-lbs person/load.

I like it, however I noticed the omission of [rear] suspension, please clarify that?

I couldn't afford it now anyway, but a full suspension frame is a must for me!

The reason is above. The rear rack is designed to seat a 2nd person.

Thanks!

[slayer]

JUST A NOTE TO SAY i just posted the latest pics today (Aug 15 2011) and i think we have a real winner here,all specs will be posted in the coming days and at this point i hope more people will want to place their deposits based on this newest design,,,place comments please,,,as we are soon ready to go into production,,,THIS IS GOING TO HAPPEN FOLKS,WE NEED THIS BIKE!

MAX

For a non-rear sus bike this is a decent design on paper. I like it.

However, I still want to know the dimension specs. I can't order unless I know:

Wheelbase w/Standard Design Fork Choice(s) Noted & any rake.

Chainstay length or Distance between Bottom Bracket & Rear Dropout (center to center).

Standover Height with typical wheels/tires choice(s).

Seat-tube & Head-tube Angles.

Please note Materials choices.

Please make sure the rear rack can seat a 200-lbs person/load.

I like it, however I noticed the omission of [rear] suspension, please clarify that?

I couldn't afford it now anyway, but a full suspension frame is a must for me!

The reason is above. The rear rack is designed to seat a 2nd person.

Thanks!

Agree to all above

i would like one with double suspension but would probably accept it like that if we can work with existing bike parts ...chain wheel etc ...it s hard to make a commitment before Max

[Willow]

where can we check out these images??

[deVries]

where can we check out these images??

See first post number 1 in this thread.

[Willow]

hmmm, ok.

Great idea, but still yet to be proven. Will there be room to easily connect the cells together, then run wiring to the other bank of batteries... There is more to this than just carrying bulk cells - like controller placement and room for other stuff like a main contactor, DC-DC converter maybe??... and a neat solution to hide all wiring and that which is not hidden be shrouded to prevent damage etc....

A skeptic at this point in time, simply because this design has not yet been resolved, and will not be resolved until at least one has been built and tested.

[maxwell65]

hi guys,,

as i said in a few days all specs will be posted,,,rear suspension may be a problem but the tires will be of the moped type which will be more than enough to handle the odd bump on the road,,,shocks will add a big expense on this project and in the end provide little use as this bike is in fact designed for paved on road use,,,not off road use,,,,so if a 100 people are willing to prepay then shocks it is,,,if not im the one stuck paying the bill here and monetarily the shocks will be prohibitive,,,,i know this bike once produced will be great without the shocks,,,and the chance to buy in on the ground floor will save big $$$ and im sure will sell for more than double the purchased price. as the price it is being offered at is pretty much rock bottom....make no mistake once this bike gets on the market there will be great interest as gas is not getting lower in cost,,,no license or registration to buy and with a range of 100 to 150 kms on one charge costing only around .20 cents and gas equivalent of 1500 to 2000 kms per gallon(no exaggeration here),,,,and no more having to jimmy up a rear bike rack to carry only 48v20ah of lifepo4 and further add to that the fact that the batteries are hanging off the sides and not centered,,,,well who can resist that?

[maxwell65]

hmmm, ok.

Great idea, but still yet to be proven. Will there be room to easily connect the cells together, then run wiring to the other bank of batteries... There is more to this than just carrying bulk cells - like controller placement and room for other stuff like a main contactor, DC-DC converter maybe??... and a neat solution to hide all wiring and that which is not hidden be shrouded to prevent damage etc....

A skeptic at this point in time, simply because this design has not yet been resolved, and will not be resolved until at least one has been built and tested.

a small note here,,,yes all these things are considered,,and as far as the argument of "at least one has been built and tested". well in fact one will be built and tested and all provisions will be made,,,and then once that one frame is given the ok then and only then will the main production take place,,,,and that is in fact part and parcel of the overall cost of making this project come to life,,,,does anyone here honestly expect that were just gonna bat out 300 frames and discover after that the frame will not hold up to normal punishment carrying 50 odd pounds of batteries and a 250lb guy? or find out there's room for the batteries but not room for the wiring? or the pedals don't pedal cause something is in the way? not gonna happen on my watch.