So uuuhm, how come noone’s talking about the high-pivot 180mm Lapierre Spicy someone posted 2 pages ago?
It was supposed to be realased last autumn but didn't. And they were on the catalogue before the team ride's it... On another note, I heard that Lapierre and the Accel Group are in financial struggle
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing claims, for mountain biking? The other (in)famous brand using it is Pole, and since their frames are machined Leo can be much more flexible in his shapes and local frame geometry, spreading out stress loads, varying wall thickness, using smarter shapes, avoiding joints that can cause load peaks, etc. But his frames are heavier than traditional aluminum welded frames and they seem to break more. This Atherton frame likely is also heavier than most traditional aluminum frames. What if we returned to the 2009 era and just used thicker aluminum tubing with less hydroforming and more gussets until the weight was comparable?
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing...
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing claims, for mountain biking? The other (in)famous brand using it is Pole, and since their frames are machined Leo can be much more flexible in his shapes and local frame geometry, spreading out stress loads, varying wall thickness, using smarter shapes, avoiding joints that can cause load peaks, etc. But his frames are heavier than traditional aluminum welded frames and they seem to break more. This Atherton frame likely is also heavier than most traditional aluminum frames. What if we returned to the 2009 era and just used thicker aluminum tubing with less hydroforming and more gussets until the weight was comparable?
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere...
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere did it. But it might be decades until that is proven to be reliable, or it might never prove to be reliable. I'm not a betting man,but I'd bet on flying cars being available before welded 7075.
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as it may not fully re-form these crucial precipitates evenly, particularly in the heat-affected zone. This process can compromise the welded area's integrity and strength, making alternatives like bonding or mechanical fastening better for maintaining 7075's high-strength qualities in critical applications.
So its likely possible, eventually, just prohibitively expensive and impractical. When I asked ChatGPT about brazing 7075, it says:
For brazing a 7075 aluminum alloy mountain bike, aluminum-silicon fillers (like 4047) are commonly used, offering a good balance between low melting point and strength. Zinc-aluminum alloys can also be considered for lower-temperature brazing, but they may not match the strength and durability required for biking stresses. Ensure the filler is compatible with 7075 aluminum and the bike's usage conditions, focusing on achieving a joint that withstands the rigors of mountain biking while maintaining frame integrity.
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing...
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing claims, for mountain biking? The other (in)famous brand using it is Pole, and since their frames are machined Leo can be much more flexible in his shapes and local frame geometry, spreading out stress loads, varying wall thickness, using smarter shapes, avoiding joints that can cause load peaks, etc. But his frames are heavier than traditional aluminum welded frames and they seem to break more. This Atherton frame likely is also heavier than most traditional aluminum frames. What if we returned to the 2009 era and just used thicker aluminum tubing with less hydroforming and more gussets until the weight was comparable?
Yes, Nicolai never left the 2000s era of indestructible aluminum frames that didn't worry about weight. I said before I've cracked every aluminum frame I've ever owned, but I never owned a Nicolai haha. Plus they are beautiful.
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere...
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere did it. But it might be decades until that is proven to be reliable, or it might never prove to be reliable. I'm not a betting man,but I'd bet on flying cars being available before welded 7075.
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as...
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as it may not fully re-form these crucial precipitates evenly, particularly in the heat-affected zone. This process can compromise the welded area's integrity and strength, making alternatives like bonding or mechanical fastening better for maintaining 7075's high-strength qualities in critical applications.
So its likely possible, eventually, just prohibitively expensive and impractical. When I asked ChatGPT about brazing 7075, it says:
For brazing a 7075 aluminum alloy mountain bike, aluminum-silicon fillers (like 4047) are commonly used, offering a good balance between low melting point and strength. Zinc-aluminum alloys can also be considered for lower-temperature brazing, but they may not match the strength and durability required for biking stresses. Ensure the filler is compatible with 7075 aluminum and the bike's usage conditions, focusing on achieving a joint that withstands the rigors of mountain biking while maintaining frame integrity.
Oh, chatGPT says! Well then it MUST be true.
Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys. Typically not for main tube joints.
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere...
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere did it. But it might be decades until that is proven to be reliable, or it might never prove to be reliable. I'm not a betting man,but I'd bet on flying cars being available before welded 7075.
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as...
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as it may not fully re-form these crucial precipitates evenly, particularly in the heat-affected zone. This process can compromise the welded area's integrity and strength, making alternatives like bonding or mechanical fastening better for maintaining 7075's high-strength qualities in critical applications.
So its likely possible, eventually, just prohibitively expensive and impractical. When I asked ChatGPT about brazing 7075, it says:
For brazing a 7075 aluminum alloy mountain bike, aluminum-silicon fillers (like 4047) are commonly used, offering a good balance between low melting point and strength. Zinc-aluminum alloys can also be considered for lower-temperature brazing, but they may not match the strength and durability required for biking stresses. Ensure the filler is compatible with 7075 aluminum and the bike's usage conditions, focusing on achieving a joint that withstands the rigors of mountain biking while maintaining frame integrity.
Oh, chatGPT says! Well then it MUST be true.
Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys...
Oh, chatGPT says! Well then it MUST be true.
Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys. Typically not for main tube joints.
Are you making any bikes soon? That Datum looks amazing.
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames...
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7000 series can absolutely be welded. All of Knolly's bikes are 7000 series and I can confirm they are definitely welded, great piece of kit too
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames...
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7000 series can absolutely be welded. All of Knolly's bikes are 7000 series and I can confirm they are definitely welded, great piece of kit too
I've only welded with an old Hobart flux core, but Knolly's site says "we use a 6066 series hydroformed aluminum alloy tubing. It's the most advanced weldable tubing alloy available".
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat treatment.
7075 is more than just a little stronger than most Al alloys, typically 525 MPa vs 290 for 6061. So less stress per unit force applied and better fatigue life, especially without the complication and inconsistency of welding.
Like most here I've had a several Al frame failures, always from fatigue at a weld. Bonding is better and more consistent once you have a design and process that works, but that isn't trivial.
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames...
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7000 series can absolutely be welded. All of Knolly's bikes are 7000 series and I can confirm they are definitely welded, great piece of kit too
7005 (or 7020, the EU equivalent of 7005) can, 7075 for all intents and purposes no. A higher ultimate strength limit will also make it more fatigue resistant. Stiffness wise it's basically no difference between the two.
For brazing you need enough surface area for the two parts to be joined, so you might as well glue the tubes in the lugs and be done with it.
7005 also needs to be heat treated, but it's cooled in air, 6000 series needs to be cooled in oil and thus requires a more complex heat treatment equipment. 6000 is more easily weldable though, so that's a benefit of it.
There will likely be more HP trail bikes for a few years, just like with through headset routing, if it turns out to be a flop, it will take another product cycle to clear then out (4ish years from now).
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat...
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat treatment.
7075 is more than just a little stronger than most Al alloys, typically 525 MPa vs 290 for 6061. So less stress per unit force applied and better fatigue life, especially without the complication and inconsistency of welding.
Like most here I've had a several Al frame failures, always from fatigue at a weld. Bonding is better and more consistent once you have a design and process that works, but that isn't trivial.
7005 is way more expensive than 6061, limited in tube sizes and much more costly when working with billet for machined parts. The advantage is the ease of aging/heat treating.
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat...
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat treatment.
7075 is more than just a little stronger than most Al alloys, typically 525 MPa vs 290 for 6061. So less stress per unit force applied and better fatigue life, especially without the complication and inconsistency of welding.
Like most here I've had a several Al frame failures, always from fatigue at a weld. Bonding is better and more consistent once you have a design and process that works, but that isn't trivial.
For the same design and same loading, stress is the same for the two materials assuming no deflection. Modulus of elasticity is the same for all intents and purposes so when you consider deflection as well it’s still pretty much the same. S-N curve is the quick and easy way to visualize fatigue. For the same stress, 7075 can handle significantly more cycles. This graph is something I found really quick so no idea how accurate it is, but conveys the point. Traced lines for stress that would cause failure in 10^4 cycles in 6061. Would require about 10^5.6 cycles for 7075 to fail under the same stress. So same part same application but 7075 instead of 6061 would last almost 40x as many cycles.
In my mind, usage of 7075 is about what it lets you do with the design. For some things the reality is it doesn’t let you do much other than take a part that’s already overbuilt and make it way overbuilt. On the other hand there are parts such as our DHX2 MX eyelet that wouldn’t be possible in 6061.
If you're stiffness limited 7075 is mostly a marketing point. Making a C section crankarm (more or less most modern cranks that are forged and/or machined) out of 7075 and thining it out to achieve the possible limits will probably just make it more noodly. Making a handlebar out of 7075 vs. 6000 series and modifying it to achieve the same fatigue limit will make it more flexy as well but this might be a lot more beneficial than crank arms.
It was supposed to be realased last autumn but didn't. And they were on the catalogue before the team ride's it... On another note, I heard that Lapierre and the Accel Group are in financial struggle
The Lapidale Spekyll
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing claims, for mountain biking? The other (in)famous brand using it is Pole, and since their frames are machined Leo can be much more flexible in his shapes and local frame geometry, spreading out stress loads, varying wall thickness, using smarter shapes, avoiding joints that can cause load peaks, etc. But his frames are heavier than traditional aluminum welded frames and they seem to break more. This Atherton frame likely is also heavier than most traditional aluminum frames. What if we returned to the 2009 era and just used thicker aluminum tubing with less hydroforming and more gussets until the weight was comparable?
Ehm, nicolai wants to have a word with you.
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as it may not fully re-form these crucial precipitates evenly, particularly in the heat-affected zone. This process can compromise the welded area's integrity and strength, making alternatives like bonding or mechanical fastening better for maintaining 7075's high-strength qualities in critical applications.
So its likely possible, eventually, just prohibitively expensive and impractical. When I asked ChatGPT about brazing 7075, it says:
For brazing a 7075 aluminum alloy mountain bike, aluminum-silicon fillers (like 4047) are commonly used, offering a good balance between low melting point and strength. Zinc-aluminum alloys can also be considered for lower-temperature brazing, but they may not match the strength and durability required for biking stresses. Ensure the filler is compatible with 7075 aluminum and the bike's usage conditions, focusing on achieving a joint that withstands the rigors of mountain biking while maintaining frame integrity.
Yes, Nicolai never left the 2000s era of indestructible aluminum frames that didn't worry about weight. I said before I've cracked every aluminum frame I've ever owned, but I never owned a Nicolai haha. Plus they are beautiful.
Chirs Canfield / Vampire Bikes' (sometime) upcoming bike with CBF + CF3 + I-Track from the 'gram:
Oh, chatGPT says! Well then it MUST be true
.
Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys. Typically not for main tube joints.
looks like a horst link high pivot (would explain the itrack patent) like the GT or new Norcos
Are you making any bikes soon? That Datum looks amazing.
7000 series can absolutely be welded. All of Knolly's bikes are 7000 series and I can confirm they are definitely welded, great piece of kit too
I've only welded with an old Hobart flux core, but Knolly's site says "we use a 6066 series hydroformed aluminum alloy tubing. It's the most advanced weldable tubing alloy available".
I just received tubes to make a couple of dozen frames. I plan on taking deposits/preorders toward the end of this month.
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat treatment.
7075 is more than just a little stronger than most Al alloys, typically 525 MPa vs 290 for 6061. So less stress per unit force applied and better fatigue life, especially without the complication and inconsistency of welding.
Like most here I've had a several Al frame failures, always from fatigue at a weld. Bonding is better and more consistent once you have a design and process that works, but that isn't trivial.
Hey Primoz!
How many HP bikes is this now, like 32 or something?
Pretty friggin cool!
7005 (or 7020, the EU equivalent of 7005) can, 7075 for all intents and purposes no. A higher ultimate strength limit will also make it more fatigue resistant. Stiffness wise it's basically no difference between the two.
For brazing you need enough surface area for the two parts to be joined, so you might as well glue the tubes in the lugs and be done with it.
7005 also needs to be heat treated, but it's cooled in air, 6000 series needs to be cooled in oil and thus requires a more complex heat treatment equipment. 6000 is more easily weldable though, so that's a benefit of it.
There will likely be more HP trail bikes for a few years, just like with through headset routing, if it turns out to be a flop, it will take another product cycle to clear then out (4ish years from now).
7005 is way more expensive than 6061, limited in tube sizes and much more costly when working with billet for machined parts. The advantage is the ease of aging/heat treating.
For the same design and same loading, stress is the same for the two materials assuming no deflection. Modulus of elasticity is the same for all intents and purposes so when you consider deflection as well it’s still pretty much the same. S-N curve is the quick and easy way to visualize fatigue. For the same stress, 7075 can handle significantly more cycles. This graph is something I found really quick so no idea how accurate it is, but conveys the point. Traced lines for stress that would cause failure in 10^4 cycles in 6061. Would require about 10^5.6 cycles for 7075 to fail under the same stress. So same part same application but 7075 instead of 6061 would last almost 40x as many cycles.
In my mind, usage of 7075 is about what it lets you do with the design. For some things the reality is it doesn’t let you do much other than take a part that’s already overbuilt and make it way overbuilt. On the other hand there are parts such as our DHX2 MX eyelet that wouldn’t be possible in 6061.
If you're stiffness limited 7075 is mostly a marketing point. Making a C section crankarm (more or less most modern cranks that are forged and/or machined) out of 7075 and thining it out to achieve the possible limits will probably just make it more noodly. Making a handlebar out of 7075 vs. 6000 series and modifying it to achieve the same fatigue limit will make it more flexy as well but this might be a lot more beneficial than crank arms.
So is the new Fox fork chassis incoming imminently? This is a GMBN journalist.
There's a new Fox fork chassis? I thought it was all internal changes for the 38. Unless this is for a 36?
Seems like MY24 is internal changes only (at least from what can be seen in the parts specs on the Fox site).
MY25 may be more extensive.
If they're testing with journalists, must mean the announcement and reviews are imminent?
I haven’t been keeping tabs lately but I’d only heard it was internal updates. I’m asking if/how we know there’s a new chassis
It's their 50th anniversary... Good excuse to do something...
Race Face with 3 upcoming releases...
https://www.raceface.com/pages/the-new-carbon-era
Likely ERA wheels/rims, handlebars and maybe something unexpected.
Some of the factory riders are riding non-Kashima forks which as it was pointed out earlier happened last right before the 38 was released.
In the IG post, the entire fork is blurred out on each bike.
Wow there’s a ride-4 chip!
Dang that’s a sweet looking Nomad
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