MTB Tech Rumors and Innovation

Related:
sethimus
Posts
870
Joined
9/20/2014
Location
CH
3/20/2024 4:07am
TimBud wrote:
Interesting comments from Ed Haythornthwaite (Robot Bike Co founder and ex Atherton) over on PB about the S170. The guy has some very good credentials, but...

Interesting comments from Ed Haythornthwaite (Robot Bike Co founder and ex Atherton) over on PB about the S170.

The guy has some very good credentials, but its hard to decide whether to take the comments seriously or with a pinch of salt as they're from an obviously disgruntled ex member of the team.

Edit:

Ty sethimus

 

too hard to take a screenshot ffs?

9
2
Primoz
Posts
4519
Joined
8/1/2009
Location
SI
3/20/2024 4:08am

And the comments are? Copy paste or Screenshots please? I'm guessing they are in the comments under the release article? 

1
sethimus
Posts
870
Joined
9/20/2014
Location
CH
3/20/2024 4:13am

how you do it right:

image-20240320121305-1

20
Primoz
Posts
4519
Joined
8/1/2009
Location
SI
3/20/2024 4:18am

Wouldn't be surprised if the novelty of bonded frames is a marketing/sales benefit over welding frames... A factor of standing out from the crowd and a possible justification for a higher price (thus possibly a higher margin). 

16
bizutch
Posts
1435
Joined
8/1/2009
Location
Fletcher, NC US
3/20/2024 5:21am
Primoz wrote:
Wouldn't be surprised if the novelty of bonded frames is a marketing/sales benefit over welding frames... A factor of standing out from the crowd and a...

Wouldn't be surprised if the novelty of bonded frames is a marketing/sales benefit over welding frames... A factor of standing out from the crowd and a possible justification for a higher price (thus possibly a higher margin). 

Guys who are tech geniuses aren't always the best marketing guru.
I get why Atherton came out with the alloy/alloy bonded frames.  It's on brand. Visual & design cues match what people expect from the brand.

Producing a welded bike would be just one more welded bike.  

And we've seen Pivot not be able to translate the aesthetic of DW-Link bikes that was so popular with Iron Horse over to their alloy frames.  I can't imagine an Atherton buyer getting even slightly stoked by "one more alloy frame".
They'd just put it next to an Ibis or Pivot and pick it apart.  

 

8
TimBud
Posts
530
Joined
2/29/2012
Location
GB
3/20/2024 5:29am
Primoz wrote:

And the comments are? Copy paste or Screenshots please? I'm guessing they are in the comments under the release article? 

Sorry, thought I had.

Rushed post before I took my wife out for lunch. I'd sooner piss off a bunch a forum nerds than her.

Lets face it though I would've got in shit with someone for daring to mention "the other site". 

7
Primoz
Posts
4519
Joined
8/1/2009
Location
SI
3/20/2024 5:43am

Don't get it what the big deal with mentioning Pinkbike is... I feel the community and the vibe there is far from good, but is there a need to skirt around the name too? It's not like we're talking about Voldermort...

30
TimBud
Posts
530
Joined
2/29/2012
Location
GB
3/20/2024 5:53am Edited Date/Time 3/20/2024 5:55am

I’ve always assumed it was one of the unwritten rules we’re not supposed to talk about.


Despite what Ed says, I’m in the market  the S170 is top of my list and i might have some funds for a frame when our house sale goes through in a few weeks… if my wifenancial advisor gives permission of course.

3
3/20/2024 6:25am
Primoz wrote:
Wouldn't be surprised if the novelty of bonded frames is a marketing/sales benefit over welding frames... A factor of standing out from the crowd and a...

Wouldn't be surprised if the novelty of bonded frames is a marketing/sales benefit over welding frames... A factor of standing out from the crowd and a possible justification for a higher price (thus possibly a higher margin). 

bizutch wrote:
Guys who are tech geniuses aren't always the best marketing guru. I get why Atherton came out with the alloy/alloy bonded frames.  It's on brand. Visual...

Guys who are tech geniuses aren't always the best marketing guru.
I get why Atherton came out with the alloy/alloy bonded frames.  It's on brand. Visual & design cues match what people expect from the brand.

Producing a welded bike would be just one more welded bike.  

And we've seen Pivot not be able to translate the aesthetic of DW-Link bikes that was so popular with Iron Horse over to their alloy frames.  I can't imagine an Atherton buyer getting even slightly stoked by "one more alloy frame".
They'd just put it next to an Ibis or Pivot and pick it apart.  

 

Spot on, for this brand to make a welded frame makes no sense from a brand/marketing lens.  The aluminum lug keeps the DNA and the exclusive feel that they started.

it also seems that Atherton is really pushing the S170 as a park, rugged bike you can beat up and it will last. It’s a cool angle because that’s how I feel with my unpainted steel bike. Just throw it in the truck, mash it, no worry for scratch or dent carbon.

5
TimBud
Posts
530
Joined
2/29/2012
Location
GB
3/20/2024 6:36am

Anyone know what the fatigue life of 7075 is?

I’ve been under the impression that an aluminium frame will have a usable life of 5 years before it starts to get “brittle”.

Is 7075 the same/similar in that respect?

 

1
Primoz
Posts
4519
Joined
8/1/2009
Location
SI
3/20/2024 6:50am Edited Date/Time 3/20/2024 6:50am

It is.

https://en.wikipedia.org/wiki/Fatigue_limit

Even more so: "The concept of endurance limit was introduced in 1870 by August Wöhler.[15] However, recent research suggests that endurance limits do not exist for metallic materials, that if enough stress cycles are performed, even the smallest stress will eventually produce fatigue failure.[7][16]"

It's the cyclic nature of the loads that mean an aluminium frame will crack sooner or later. It's not a years thing, it's a number of cycles, severity of the loads and the design that dictate when a crack will start forming.

13
3/20/2024 7:47am
TimBud wrote:
Anyone know what the fatigue life of 7075 is? I’ve been under the impression that an aluminium frame will have a usable life of 5 years...

Anyone know what the fatigue life of 7075 is?

I’ve been under the impression that an aluminium frame will have a usable life of 5 years before it starts to get “brittle”.

Is 7075 the same/similar in that respect?

 

IIRC one of the main advantages of 7075 over 6061 is improved fatigue life. 

I'm not an expert, I'm sure someone more knowledgeable will correct me if I'm off base. 

1
3/20/2024 7:53am
TimBud wrote:
Anyone know what the fatigue life of 7075 is? I’ve been under the impression that an aluminium frame will have a usable life of 5 years...

Anyone know what the fatigue life of 7075 is?

I’ve been under the impression that an aluminium frame will have a usable life of 5 years before it starts to get “brittle”.

Is 7075 the same/similar in that respect?

 

Every aluminum frame I've ever owned has cracked, even my scandium Konas. Clearly, in practical applications for mountain bikes, 7075 isn't lighter than traditional welded 6000 series aluminum, so I hope it does have a longer "endurance limit" for mountain bike applications.

3
1
Primoz
Posts
4519
Joined
8/1/2009
Location
SI
3/20/2024 7:54am

Overall ultimate tensile strength is the benefit of 7075 which in turn makes the fatigue limit higher, meaning it will deal with either higher load severity with the same number of cycles or more cycles at the same load severity. 

7
Dave113
Posts
42
Joined
3/7/2018
Location
Lafayette, CO US
3/20/2024 8:18am

Welding is the biggest liability and point of failure on an Al frame. Avoiding welding removes a factor that relies on human skill and is hard to control, although before the switch to C, Al welding and forming was getting much better, the top end Al frames ~10 years ago or so were pretty nice and it looked like many welds were automated. These days though, Al is made heavy and cheap. 

I agree with Primoz about 7075, UTS is much higher, this can definitely be used to increase reliability or cut weight. I don't understand the thought that 7075 doesn't offer some major advantages over 6000 series Al.

IMO, outside of high end automated welding and forming of Al, which nobody does anymore, avoiding a welded Al frame makes a lot more sense to me. 

10
1
Big Bird
Posts
2280
Joined
2/1/2011
Location
Oceano, CA US
3/20/2024 11:44am

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? 

3/20/2024 12:34pm
Big Bird wrote:
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? 

7005 (and some others in 7000-series) is weldable, when welding 7075 is "not recommended" (can't exactly explain why tho'...).

1
Digit Bikes
Posts
180
Joined
9/22/2021
Location
Irvine, CA US
3/20/2024 12:35pm
Big Bird wrote:
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? 

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.

3
OldManCook
Posts
27
Joined
2/13/2024
Location
Christchurch NZ
3/20/2024 12:42pm

learnt so much about welding..  Wink i need some mods to a trailer i have.. any takers Smile

you guys really love welding and brakes.. 

5
3/20/2024 12:47pm

So uuuhm, how come noone’s talking about the high-pivot 180mm Lapierre Spicy someone posted 2 pages ago? Smile

2
nicompr
Posts
55
Joined
12/9/2021
Location
Villes FR
3/20/2024 1:00pm

So uuuhm, how come noone’s talking about the high-pivot 180mm Lapierre Spicy someone posted 2 pages ago? Smile

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

9
1
monarchmason
Posts
285
Joined
5/24/2022
Location
Nevada City, CA US
3/20/2024 1:03pm

So uuuhm, how come noone’s talking about the high-pivot 180mm Lapierre Spicy someone posted 2 pages ago? Smile

The Lapidale Spekyll

8
3/20/2024 1:47pm

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? 

1
Jakub_G
Posts
352
Joined
8/7/2019
Location
SK
3/20/2024 1:59pm
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? 

Ehm, nicolai wants to have a word with you.

2
3/20/2024 2:11pm
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.

 

2
9
3/20/2024 2:13pm
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? 

Jakub_G wrote:

Ehm, nicolai wants to have a word with you.

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.  

2
MTBrent
Posts
104
Joined
7/7/2015
Location
Concord, NH US
3/20/2024 2:29pm Edited Date/Time 3/20/2024 2:32pm

Chirs Canfield / Vampire Bikes' (sometime) upcoming bike with CBF + CF3 + I-Track from the 'gram:

Screenshot 2024-03-20 at 5.19.47%E2%80%AFPM

 

14
Digit Bikes
Posts
180
Joined
9/22/2021
Location
Irvine, CA US
3/20/2024 2:51pm Edited Date/Time 3/20/2024 3:11pm
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 trueSilly.

Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys. Typically not for main tube joints.

11
3/20/2024 2:58pm
MTBrent wrote:
Chirs Canfield / Vampire Bikes' (sometime) upcoming bike with CBF + CF3 + I-Track from the 'gram:  

Chirs Canfield / Vampire Bikes' (sometime) upcoming bike with CBF + CF3 + I-Track from the 'gram:

Screenshot 2024-03-20 at 5.19.47%E2%80%AFPM

 

looks like a horst link high pivot (would explain the itrack patent) like the GT or new Norcos

Puneta
Posts
54
Joined
12/28/2022
Location
Phoenix, AZ US
3/20/2024 4:32pm
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 trueSilly.

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. 

Post a reply to: MTB Tech Rumors and Innovation

This forum thread has been locked.

The Latest