10kw Carbon build possible????

[richdeloup]

Interesting stuff, especially liking this http://bustedcarbon.com

My frame thoughts were more that the outer carbon shell would almost become a mould for a stiff internal structure, which was linked together with some sort of rod system and encased in some sort of resin, hopefully poured in one go.

Again I have absolutely no experience of this, so all thoughts are really helpful, just thought that id give it a go. I wish I had access to test facilities like Doc but I will be doing the tried and tested method of dressing up like the Michelin man and saying a prayer

 

[richdeloup]

plettenberg-motoren

I want one just for the name!Its funny how anything to do with engineering and written in German sounds cool. They must have a good marketing strategy, vorsprung dirk technique maybe?

 

[richdeloup]

I've used approx 20% to fill the chainstays; I'm figuring that I could do the whole frame with these bottles and some matting/rod material, so hopefully not exceeding 1kg added weight (not including dropouts and alu battery U section)??

 

[Chalo]

Metal matrix or amorphous metal for the win.

From Wikipedia:

" One modern amorphous metal, known as Vitreloy, has a tensile strength that is almost twice that of high-grade titanium. However, metallic glasses at room temperature are not ductile and tend to fail suddenly when loaded in tension, which limits the material applicability in reliability-critical applications, as the impending failure is not evident. "

Sounds like just the thing for a bike frame. (Not.)

 

[liveforphysics]

richdeloup, let me answer to your thread question:

Yes Possible !! 8)

DONE already!

My secret project! :wink:

100% carbon fiber frame! with 16L of battery room .. in fact you could put like 5kWh of lithium cells into it !

SPECIALY MADE FOR THE REAL EBIKE POWER REQUEST !!

I have Equiped it with :

Adaptto 12kW
Zero 1.8 kWh battery 22s1p ( an original 28s1p Zero Motorcycle ZF2.8 pack splitted in two half for 22s)
5302 motor

60T front sproket made to be able to pedal even at 80km/h!!.

400A 92V

The frame is undestructible !! some specialist that tested it say it is way too much strong!! ... that sound very good to me!!!

btw dont pay attention to the rediculous rear tire... it's because i just blown my rear motocross 16 x 3.5 tire after too much tire burn out demo! I only had this little 2.25 x 20 to replace it yet... lol

More détails coming soom about that insane frame kit !!

btw... it has nothing to do with steel or aluminum frame covered with " carbon fiber" vynil!! it's a thick 100% carbon fiber frame battery box!!

Stay tuned!

Doc

I will be building one of these. With one of JohninCR's hubmonsters and a 12kW adapto.

 

[boisrondevens]

Sorry but I think the question was not about if a carbon fiber frame can be strong enoug for a 10kwbike drive.
If you take a prefabricated carbon bike frame And put a 10kw drive to it, can it withstand the power: no
Can you costom made a carbon frame for a ebike with 10kw or more: yes

And btw carbon is being use in the automobile and motocycle industry for years but never i the structural comportenant of the frame...


Sorry for my bad English ( I'm French from Montreal)

 

[richdeloup]

@boisrondevens

The title question was mean to mean more along the lines of
'I wonder if I can buy one of those cheap blank Chinese carbon frames and strengthen it to take 10kw, hmm lets try'

More of a question to myself if you see what I mean, however a good discussion for those who took it literally

 

[richdeloup]

Revolt 45kV on its way, my pockets aren't deep enough for the Plettenberg-motoren...

 

[Merlin]

Surely there's nothing structural about this bit?? Thinking it may be a good place for series disconnect plug/charging port?

iam not that kind of cfk professional, but what will you do with this grinded opened frame?
i dont think that it is a good idea what i see on your pics.
Why did you "opened" that Frame like this?

 

[richdeloup]

iam not that kind of cfk professional, but what will you do with this grinded opened frame

I needed to open it up as much as possible to route cables through and to strengthen. Like mentioned before, I'm almost looking at the carbon shell as a mould for an internal structure which will encase all the cabling. Its totally experimental and may not work, however am going to run the cables up the seat post and into the controller mounted in a saddle bag. Everything will then be reinforced with tied together carbon rods encased in Alumilite.

Alumilite is what they cast fishing rods and things like that from. Its pretty unbreakable and should still give a slight flex to the frame. From the work that I did on the chainstays, I think that the end structure will be far more capable than the original, that's why I'm not too fussed about chopping it up

I'm really going for the stealthiest look which holds everything internally and will hopefully be indistinguishable from a normal bike, apart from the Revolt motor!

 

[richdeloup]

One other point. After looking through loads of broken carbon frame pics, one of the most common areas for failure is around the joins, which really are just glued together. The whole pivot area need strengthening and the top tube needs keying into the seat post tube somehow.
The only previous experience of this sort of thing, is when tying together concrete foundations with metal rods, so this is what I'm working on, all be it for a totally different application., will it work???

 

[Rix]

One other point. After looking through loads of broken carbon frame pics, one of the most common areas for failure is around the joins, which really are just glued together. The whole pivot area need strengthening and the top tube needs keying into the seat post tube somehow.
The only previous experience of this sort of thing, is when tying together concrete foundations with metal rods, so this is what I'm working on, all be it for a totally different application., will it work???[/quote]

I don't know, but the fact that its possible for a frame to break, and you are willing to try it, tells me one thing about you, you got ballz that clank man.

 

[liveforphysics]

One other point. After looking through loads of broken carbon frame pics, one of the most common areas for failure is around the joins, which really are just glued together. The whole pivot area need strengthening and the top tube needs keying into the seat post tube somehow.
The only previous experience of this sort of thing, is when tying together concrete foundations with metal rods, so this is what I'm working on, all be it for a totally different application., will it work???

It's possible to take carbon tow, saturate it in epoxy, and wrap a frame joint to strengthen it as much as desired. You can buy carbon tow and epoxy on ebay cheap. However, it wouldn't make the members between the joints stronger. I think the wise path to a carbon ebike is buying that frame Doc showed.

 

[richdeloup]

I don't know, but the fact that its possible for a frame to break, and you are willing to try it, tells me one thing about you, you got ballz that clank man.

In an age of health and safety, its quite satisfying to piss into the wind sometimes

I think the wise path to a carbon ebike is buying that frame Doc showed.

Agreed if looking to buy a frame that you know's going to work. I'm more building this for the ride, i.e I have plenty of bikes I can jump on to get me from A to B, this is more to fulfil my winter evening modification fetish.
Also I want to experience the ride qualities (or not?) of a scaled back lightweight, powerful build, even if it only gets me a few miles up the road.

 

[richdeloup]

Its prob sacrilege posting this on here but these guys are my inspiration for fingers up to safety builds
https://www.youtube.com/watch?v=D1EHZPjLNHk&list=PLGjbAdaOBLBnIoUrJqPAuRe38kvcQ9_V7

http://bmx.transworld.net/videos/guy-goes-207mph-bike/

And of course Luke's Death bike

 

[Samer]

HEy Doc put some video on of this machine looking sick...

 

[Rix]

HEy Doc put some video on of this machine looking sick...

Samer, I sent him a PM asking similiar details. Doc, whats up??

 

[Doctorbass]

HEy Doc put some video on of this machine looking sick...

Samer, I sent him a PM asking similiar details. Doc, whats up??

ery Soon guys.. just let me have time to play with! i am tuu busy now at work and at home with preparation for winter :?

I will détail this very great frame no worrie!

Doc

 

[richdeloup]

Anyone want to buy a chopped up carbon frame going cheap?
just kidding, frustration, oh how I love it :?

 

[Rix]

Anyone want to buy a chopped up carbon frame going cheap?
just kidding, frustration, oh how I love it :?

Sound a little like Drunk Skunk when he was building his frame.

 

[macribs]

carbon is not stiff it is flexible hence why a carbon frame feels smoother to ride as it absorbs some of the shock, it is after all plastic and cloth, it is strong for its weight but is not stronger than steel unless it is made much thicker than equivalent steel and even then its strength only lies in tensile strength it will not take impact, shock or abrasion like steel will,
tbh i dont really see the point in using carbon for a 10kw electric bike which is going to have a heavy motor and battery as what difference is the weight saved on the frame going to make? i would rather have the peace of mind that its not suddenly going to snap in 2 when hitting a heavy bump at speed, if it is just for the look of carbon then i would box the steel frame in it, this would also reduce the cost rather significantly.
im not saying a carbon frame couldnt be used but a carbon bicycle frame would not be sufficient to carry the extra weight in the majority of cases, you would need to look at something designed for a motorcycle and even when they use a carbon frame for a motorcycle it is used in conjunction with other weight saving parts in the engine and so forth.
the docs bike is of course very nice indeed but is only part carbon and that which is carbon is designed in such a way that it will have more strength than the average carbon bike frame but the same look could be achieved with a steel internal frame and i dont think the extra weight will make any significant difference on a 10kw ebike

Carbon is incredible material. Years ago I used to build custom kayaks for white river kayaking, mostly in fiber glass. Those where heavy but ok. My colleague did a few carbon for white river and water falls and the ones he did in carbon was insanely light, durable and strong as tanks. Feather compared to the ones I made in fiber glass.

For more then 10-15 years carbon has also been the core material in various monocoque builds. From one off's custom builds sports cars, to serial production sports cars to various racing vehicles. I think people tend to fear carbon for no good reason. There are ways to insure proper dimensions. And you can alter the threads, vary the thickness and add more layers in all stress parts. Basically it will be strong a fcuk and 2-3 times lighter then steel. The founder of Phasor bikes did plenty of 3-5 feet drops with his carbon frame. And I think he also was past 10kw.

So to recap, carbon have proved itself over and over. If you do the build in a proper way there is no need for fear. Other thing will give before the frame.

I see people getting hot headed over other folk riding with moto wheels because of the extra weight, and often they don't think about the 10-15 lbs they carry in the rear hub. Rotating as well.
If you have carbon frame, you opt for light weight RC motor. Use a lighter battery pack. It will do wonder for handling.

 

[Chalo]

All-CFRP construction is well proven to handle 1000+ HP in Formula 1 and Indy cars. Those cars are not very fault tolerant, but they work as designed.

However... a commercial bicycle frame isn't an F1 car. it's designed for something like 1/2 HP continuous and maybe 2HP transient power peaks. It's moderately fault tolerant at that power level. So what the OP is talking about is like taking a racing go-kart and beefing it up here and there so you can put in a Formula 1 engine. It's not really a problem of material, although the design-sensitive nature of the material is part of the problem.

The thing about metal bikes that makes them better choices for powered bike conversions is the isotropic nature of metal, plus its intrinsic toughness. Once you lay in enough metal to deal with the biggest forces you anticipate in one direction, it can tolerate similar size forces in other orientations. CFRP isn't like that. You lay fibers to withstand the forces you foresee, but they are next to useless to resist forces oriented in different directions. For example:

That's a Trek Madone, which is a competent mass-market racing bike made of CFRP. In this particular example, the factory furnished wheel reflector came out of position on a test ride and speared straight through the bike's chainstay. It's a strong bike when used as directed-- but when something unexpected happened, it might as well have been made out of cardboard.

That's the problem with anisotropic materials like carbon-plastic for DIY retrofits. They can be very good at doing what they were intended to do, but totally unsuited to dealing with anything they weren't intended to do.

 

[speedmd]

That is what you get when you mix cheap ass stuff with a great product and make it even too cheap to stay put. They could have used tape reflectors on the rims side walls instead of something that was cool in the 1950's with the other standard equipment like the peewee style streamer bar ends and a ding ding bell!

Yes, if you break it, you can get splinters. Nasty ones! Bike frames are designed to be stiff and most are many times stronger than they need to be to keep from breaking. Don't fault folks for tying to take advantage of a bit less material weight when it clearly is strong and reliable if built correctly. BTW, easy repair on the trek. Bet some one of your friends grabbed it and patched it up.

 

[Chalo]

The point is not whether or not the bike should have been fitted with wheel reflectors. It's that this never would have happened to a bike made of metal, no matter how lightweight and race-oriented.

A coaster brake or drum brake is a normal bike part. Would you put a steel brake arm strap on the carbon bike in the picture? I wouldn't.

On the other hand, an electric motor really isn't a normal bike part, at least not in the sense of having been taken into account during the design of the bike. And a 10kW motor hasn't been considered during the design of any bicycle.

Apropos reflectors: The CPSC requires manufacturers to furnish front, rear, and wheel reflectors with all complete bikes. The shop does not have to install them (though a liability-sensitive shop often will), and of course the buyer can use them or not at his discretion. I put them on, because almost all the bikes my shop sells are used for daily transportation on the street.

 

[speedmd]

It's that this never would have happened to a bike made of metal

Maybe not, but may have dented the tube to the point of seeing early failure. Who puts coaster brakes on a carbon racing bike? DORK ALARM!! Who puts / leaves 2 ounce reflectors on a set of comparable racing wheels that would honor a high end carbon frame? If your building a 200 watt commuter, I don't argue your well made points, but clearly the OP is pushing the envelope of real possibilities and no place to throw cold water on his mission. Wonder what rocket man would say? :lol: