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While I agree I think there’s a possibility of them adding the carbon wheels as an option And that’s only because bmw said they are stronger than the cast ones. It’s just hard to know operational life. They build a lot of structual car parts out of it so I don’t think they’d be to far from bikes and bmw will have to bring a game changer.
Stronger.....in a perfect world under perfect conditions maybe. I sit right next to a degreed Mechanical Engineer (who previously worked with the United Launch Alliance) and we were discussing this just the other day. We're working on the Dream Chaser and the main structural components (the chassis, if you will), is C/F, BUT, almost everything else is ti or aluminum, and we have to be extremely careful what loads we put into the C/F, so we don't punch holes in it. also, we have to be extremely careful to bias the design so that we put almost all of our C/F in tensile loading. sometimes we put big aluminum or ti doublers on it to take the load. Also, while metals are almost completely unaffected from a strength standpoint by heat (from an engine if used in the frame), or long periods of sunlight, or cold temps, C/F has serious issues with those, especially when combined. He said that there were originally a lot of parts designed/made in C/F on the Delta project, they later had to redesign/make almost all of them in aluminum or ti because of the degradation in strength of the C/F in the real world. Heat can cause delamination in C/F, causing catastrophic failure. C/F, like any plastic, has extreme notch sensitivity, unlike metals. Also, C/F, like any plastic, is far more sensitive to being brittle when cold than a metal. Further, C/F has issues with long-term exposure to UV, unlike metal.

So while C/F is great for perfect world lab testing, it has real problems with real-world long-term use.

This is why IMO you're not going to see regular production bikes with C/F wheels and frames. Non-structural bodywork, sure, structural members like the frame or even rear subframe, no. You're seeing a lot more (though not a LOT of) C/F non-structural body panels, or maybe semi-structural roof panels, but you're not going to see full C/F chassis in street cars outside of limited-use bazillion-dollar McLarens etc. It's simply a limitation of the material itself in real-world conditions.

As far as 'Gooch's comment: "You don't tool up a production line to create mass production finish times to only produce 750 units. Carbon frames are coming.", I had not read anywhere about BMW tooling up a production line to produce MASS quantities. 750 units, for sure, setting up a line to produce 'RR quantities? Nope.

Think about it, the first McLaren F1 was C/F, and people at the time said C/F chassis would be on regular production cars in a few years, and......?
 

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Stronger.....in a perfect world under perfect conditions maybe. I sit right next to a degreed Mechanical Engineer (who previously worked with the United Launch Alliance) and we were discussing this just the other day. We're working on the Dream Chaser and the main structural components (the chassis, if you will), is C/F, BUT, almost everything else is ti or aluminum, and we have to be extremely careful what loads we put into the C/F, so we don't punch holes in it. also, we have to be extremely careful to bias the design so that we put almost all of our C/F in tensile loading. sometimes we put big aluminum or ti doublers on it to take the load. Also, while metals are almost completely unaffected from a strength standpoint by heat (from an engine if used in the frame), or long periods of sunlight, or cold temps, C/F has serious issues with those, especially when combined. He said that there were originally a lot of parts designed/made in C/F on the Delta project, they later had to redesign/make almost all of them in aluminum or ti because of the degradation in strength of the C/F in the real world. Heat can cause delamination in C/F, causing catastrophic failure. C/F, like any plastic, has extreme notch sensitivity, unlike metals. Also, C/F, like any plastic, is far more sensitive to being brittle when cold than a metal. Further, C/F has issues with long-term exposure to UV, unlike metal.

So while C/F is great for perfect world lab testing, it has real problems with real-world long-term use.

This is why IMO you're not going to see regular production bikes with C/F wheels and frames. Non-structural bodywork, sure, structural members like the frame or even rear subframe, no. You're seeing a lot more (though not a LOT of) C/F non-structural body panels, or maybe semi-structural roof panels, but you're not going to see full C/F chassis in street cars outside of limited-use bazillion-dollar McLarens etc. It's simply a limitation of the material itself in real-world conditions.

As far as 'Gooch's comment: "You don't tool up a production line to create mass production finish times to only produce 750 units. Carbon frames are coming.", I had not read anywhere about BMW tooling up a production line to produce MASS quantities. 750 units, for sure, setting up a line to produce 'RR quantities? Nope.

Think about it, the first McLaren F1 was C/F, and people at the time said C/F chassis would be on regular production cars in a few years, and......?
bmw i3 frame is made from carbon fiber so they have the fixed assets in place, just reworking of tooling

bicycle frame and wheels are now carbon fiber, with great strength and durability

not all carbon fiber is the same, are there grade differences like in aluminum 6061 vs 1100?
 

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Not sure what that is, but for the i3, it's $53,000+ for a tiny, limited-production electric car that absolutely has to be lightweight to be efficient? And I'll bet BMW actually loses money on every one of them. It's a tech showcase for them and they're ok with losing money on it.

Also, from the design, I don't think the frame will see near the heat the 'RR frame will, and it'll also be covered and safe from UV exposure.
 

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bmw i3 frame is made from carbon fiber so they have the fixed assets in place, just reworking of tooling

bicycle frame and wheels are now carbon fiber, with great strength and durability

not all carbon fiber is the same, are there grade differences like in aluminum 6061 vs 1100?
That's a hell of a "rework" from a car frame made of C/F and aluminum, to a M/C frame made of C/F with aluminum inserts.

There are certainly different grades, and the amount of layers, and direction and type of the layers makes a huge difference. We have some areas where the skin will double or more in thickness where it is attached to the load-bearing metal parts. 1100 aluminum is soft, but good in corrosion resistance (kitchenware, etc.), worthless for structures. 6061 is your typical average-grade aluminum. Nothing special at all, but cheap enough and easy to machine, can be formed (sheet metal), and can be welded ok. A good all-around grade but nothing special or particularly stiff/strong. We use 6061 for all the things that aren't heavily loaded. For the more critical stuff, we typically use 2024 or 7075 if we really need it, their tensile and yield values being about double that of 6061.

As mentioned, bicycle frames and wheels do not see the thermal extremes or vibration that a M/C frame will. And, as I remember and mentioned, I've seen a bunch of sudden total failures of C/F bike frames and wheels. and a failure on a bicycle at 2mph is a whole different story than a motorcycle failure at 190mph, just sayin'......
 

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Stronger.....in a perfect world under perfect conditions maybe. I sit right next to a degreed Mechanical Engineer (who previously worked with the United Launch Alliance) and we were discussing this just the other day. We're working on the Dream Chaser and the main structural components (the chassis, if you will), is C/F, BUT, almost everything else is ti or aluminum, and we have to be extremely careful what loads we put into the C/F, so we don't punch holes in it. also, we have to be extremely careful to bias the design so that we put almost all of our C/F in tensile loading. sometimes we put big aluminum or ti doublers on it to take the load. Also, while metals are almost completely unaffected from a strength standpoint by heat (from an engine if used in the frame), or long periods of sunlight, or cold temps, C/F has serious issues with those, especially when combined. He said that there were originally a lot of parts designed/made in C/F on the Delta project, they later had to redesign/make almost all of them in aluminum or ti because of the degradation in strength of the C/F in the real world. Heat can cause delamination in C/F, causing catastrophic failure. C/F, like any plastic, has extreme notch sensitivity, unlike metals. Also, C/F, like any plastic, is far more sensitive to being brittle when cold than a metal. Further, C/F has issues with long-term exposure to UV, unlike metal.

So while C/F is great for perfect world lab testing, it has real problems with real-world long-term use.

This is why IMO you're not going to see regular production bikes with C/F wheels and frames. Non-structural bodywork, sure, structural members like the frame or even rear subframe, no. You're seeing a lot more (though not a LOT of) C/F non-structural body panels, or maybe semi-structural roof panels, but you're not going to see full C/F chassis in street cars outside of limited-use bazillion-dollar McLarens etc. It's simply a limitation of the material itself in real-world conditions.

As far as 'Gooch's comment: "You don't tool up a production line to create mass production finish times to only produce 750 units. Carbon frames are coming.", I had not read anywhere about BMW tooling up a production line to produce MASS quantities. 750 units, for sure, setting up a line to produce 'RR quantities? Nope.

Think about it, the first McLaren F1 was C/F, and people at the time said C/F chassis would be on regular production cars in a few years, and......?
Yea I don’t disagree but there was a video released by bmw about the build of the hp4 race and they had a slow motion video of them driving a carbon wheel into a ledge and it not breaking but in the same test a forged wheel did. That’s the only reason I was thinking it’s possible. Controlled test and yes I’d be interested to see the life of the wheel in real world circumstances but they also said they’ve been using carbon roofs since the 90s which are a major structural part of a car and that just cooks day in day out which is why they are confident about the frame. I’m definitely skeptical but I can dream aha.
 

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Yea I don’t disagree but there was a video released by bmw about the build of the hp4 race and they had a slow motion video of them driving a carbon wheel into a ledge and it not breaking but in the same test a forged wheel did. That’s the only reason I was thinking it’s possible. Controlled test and yes I’d be interested to see the life of the wheel in real world circumstances but they also said they’ve been using carbon roofs since the 90s which are a major structural part of a car and that just cooks day in day out which is why they are confident about the frame. I’m definitely skeptical but I can dream aha.
Are you talking about this absurd video where they show the same video footage 3 times and claim the alloy wheel failed?

I wasn't able to find any video of anyone driving a wheel into a ledge. I'd love to see that.

As the Engineer I talked with said, after lots of heat cycles, or any sharp impact, C/F has issues. Also, that video wasn't anywhere near the impact my (idiot) buddy had when he hit the curb. Yes his wheel needed to be replaced because it had a big dent in it, BUT, it didn't shatter like C/F would have, and it didn't suddenly lose all it's air pressure. It had a slow leak. In other words, he was able to ride home on it. Indeed, being the idiot as I said, he rode on it for a month or so until he could afford a new wheel.

The roof panel is what I'd call a semi-structural. Yes, it DOES take some load, but you can remove the whole thing and the car won't fold up like your frame would if it cracked. Also, the heat from the sun is nothing like the heat the engine puts into the frame.
 

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Also, after every test, I'd like to see full radiographic inspection of both alloy and C/F wheels, especially the C/F wheels. You can easily have internal delaminations that are not visible to the naked eye.
 

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Speaking of CF, I would not trust it on anything important. Here is a CF heel guard on my R1 Attacks rearset.

At Barber, a RR rider stuffed me into turn 5 (RRs be hatin' >:)), I heel hook (outside foot), stood up the bike. I did not realize my heel guard broke until the next session when I felt unstable. I replaced both CF heel guards with alum ones. I talked to Attacks folks, they said their sponsored racers only use alum and with my riding style they suggested to go with it. I ain't even a racer and CF cannot handle a bit of pressure. Not sure how I feel about a CF frame or wheels. I' guessing the HP4R won't last one season with my riding lol.

 

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True this. We need a poll. And a bet jar.

So far we have Cycle Monkey's Avatar. Not worth much, but it's a start.
A Gentleman's Bet, is worth far more than mere money, sir.... :)
 

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Speaking of CF, I would not trust it on anything important. Here is a CF heel guard on my R1 Attacks rearset.

At Barber, a RR rider stuffed me into turn 5 (RRs be hatin' >:)), I heel hook (outside foot), stood up the bike. I did not realize my heel guard broke until the next session when I felt unstable. I replaced both CF heel guards with alum ones. I talked to Attacks folks, they said their sponsored racers only use alum and with my riding style they suggested to go with it. I ain't even a racer and CF cannot handle a bit of pressure. Not sure how I feel about a CF frame or wheels. I' guessing the HP4R won't last one season with my riding lol.

That's a perfect example of an extremely poor use of C/F. You have a long lever, the possibility of a lot of force, too thin material thickness, and the stress concentrator of the relatively sharp edge of the bolt head, PLUS an incorrect hole-to-edge spacing. We use 3 x the diameter of the fastener from the edge to the centerline of the hole, and 6 x fastener diameter from hole to hole to prevent this. Poor design all around. Metal is definately the way to go on this one.

Obviously, this part was designed for blingin', not ridin'. :)
 

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I'm 99.9% sure today's "critical function" carbon fiber is vastly superior and can be tailored for desired purposes unlike CF of yesteryear. MotoGp riders are using tune-able flex fork tubes for tracks that require more or less flex in the front. BMW would not release CF wheels or frames if not sound. 750 multi-million dollar law suits would put them out of business. On the same note, I'm sure today's CF wheels from BST, Dymag and Rotobox are superior to what they were producing 2-5 years ago. They would never admit it for liability reasons. :wink2: Attack rear set CF is for looks only. Of course @z00 can destroy anything. :laugh:
 

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Are you talking about this absurd video where they show the same video footage 3 times and claim the alloy wheel failed?
https://www.youtube.com/watch?v=NSPFLYcljgI

I wasn't able to find any video of anyone driving a wheel into a ledge. I'd love to see that.

As the Engineer I talked with said, after lots of heat cycles, or any sharp impact, C/F has issues. Also, that video wasn't anywhere near the impact my (idiot) buddy had when he hit the curb. Yes his wheel needed to be replaced because it had a big dent in it, BUT, it didn't shatter like C/F would have, and it didn't suddenly lose all it's air pressure. It had a slow leak. In other words, he was able to ride home on it. Indeed, being the idiot as I said, he rode on it for a month or so until he could afford a new wheel.

The roof panel is what I'd call a semi-structural. Yes, it DOES take some load, but you can remove the whole thing and the car won't fold up like your frame would if it cracked. Also, the heat from the sun is nothing like the heat the engine puts into the frame.
Na it’s a bmw video of them explaining why their wheels they designed for the hp4race were so good. I’ll see if I can find it
 

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I'm 99.9% sure today's "critical function" carbon fiber is vastly superior and can be tailored for desired purposes unlike CF of yesteryear. MotoGp riders are using tune-able flex fork tubes for tracks that require more or less flex in the front. BMW would not release CF wheels or frames if not sound. 750 multi-million dollar law suits would put them out of business. On the same note, I'm sure today's CF wheels from BST, Dymag and Rotobox are superior to what they were producing 2-5 years ago. They would never admit it for liability reasons. :wink2: Attack rear set CF is for looks only. Of course @z00 can destroy anything. :laugh:
I wasn't aware MotoGP were using C/F fork tubes. I thought the material was banned for structural items. I believe I posted the rules on that. Hmmmm......

Remember the exploding Pinto? The Ford explorer with rollover issues? The Corvair? The recent Japanese airbag issues? Don't be so sure any manufacturer wouldn't put something into production that was later found to be a huge mistake. It's hard to get a bad metal part (unless it's from china), it's extremely easy to get a bad C/F part just because of it's very nature.

Like I said, for an extremely-limited-production run of bikes that will be cared for by professionals and coddled by their owners, with very few (if any) miles put on them at all, especially in real-world heat soak conditions, something like a C/F frame would be ok. For real world conditions with the conditions I mentioned over years of use and abuse, well.....we'll see. all these tests are with brand new parts, that have not been subjected to years of use and abuse. Metal will not degrade in material properties, C/F can and will. :)

I'm stoked to think of winning my first of the 2 Gentleman's Bet's in the not-too-distant future! :)
 

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Shazam!!!
https://www.asphaltandrubber.com/motogp/ducatis-secret-weaponcarbon-fiber-ohlins-fork-tubes/

BTW, that's a reference to Billy Batson, not the App, of the same name.

I wasn't aware MotoGP were using C/F fork tubes. I thought the material was banned for structural items. I believe I posted the rules on that. Hmmmm......

Remember the exploding Pinto? The Ford explorer with rollover issues? The Corvair? The recent Japanese airbag issues? Don't be so sure any manufacturer wouldn't put something into production that was later found to be a huge mistake. It's hard to get a bad metal part (unless it's from china), it's extremely easy to get a bad C/F part just because of it's very nature.

Like I said, for an extremely-limited-production run of bikes that will be cared for by professionals and coddled by their owners, with very few (if any) miles put on them at all, especially in real-world heat soak conditions, something like a C/F frame would be ok. For real world conditions with the conditions I mentioned over years of use and abuse, well.....we'll see. all these tests are with brand new parts, that have not been subjected to years of use and abuse. Metal will not degrade in material properties, C/F can and will. :)

I'm stoked to think of winning my first of the 2 Gentleman's Bet's in the not-too-distant future! :)
 

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Shazam!!!
https://www.asphaltandrubber.com/motogp/ducatis-secret-weaponcarbon-fiber-ohlins-fork-tubes/

BTW, that's a reference to Billy Batson, not the App, of the same name.
Interesting. I'll have to read the rules again, perhaps it's just banned for wheels.

Looks like C/F and aluminum combination (ends), wonder if it isn't thin-wall aluminum tube with an overwrap of C/F, or if the entire tube is C/F in that center section. To get tuned flex in a solid aluminum tube, all they'd have to do is make the center section (not where it mates with the triple clamps) oval shaped. Done.
 
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