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What have you broken on your bike recently?

Muddy

ancient crusty bog dude
Jul 7, 2013
2,032
908
Free Soda Refills at Fuddruckers
Read that twice and still confiused.
Are you saying you're using SRAM XO (T type mtb cassette, chain and deraileur) on a roadbike with a 39/52 double chainset?
No, no. This added chain noise would happen, on other bikes, when either messing w/ chain lengths or trying to rely on B-Limit for cassette swaps. ...never have tried a 52t CR. You like those??

Transmission is on a Trail Bike, full XX.

Some extraordinarily strange syntax going on in there!
Funny thing, syntax. I saw 'Wedding Crashers' accidentally. I bought a ticket for 'Grizzly Man' and went into the wrong theater. After an hour, I figured I was in the wrong theater, but I kept waiting. Cuz that’s the thing about bear attacks… they come when you least expect it.
 
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bullcrew

3 Dude Approved
Read that twice and still confiused.
Are you saying you're using SRAM XO (T type mtb cassette, chain and deraileur) on a roadbike with a 39/52 double chainset?
Well I didn't read it all and it makes no sense...I just read your response and man I am all over the place with confusion...I'm afraid to read his and compound my confusion at my age...

Someone just put a simple answer I can understand and keep it really short...I'm a picture guy
 

Gary

"S" is for "neo-luddite"
Aug 27, 2002
7,804
5,713
UK
...never have tried a 52t CR. You like those??
Haven't ridden one since the 90s when taller gearing (and lower cadences) was the norm. I rode way more and was waaay fitter and lighter back then so honestly didn't ever mind having a 52/42 chainset paired with an 11-23 cassette. ignorance being bliss. (I still don't like big sprocket jumps in my gearing though)


You brought up large chainrings
once dropping to the 39T CR from the 53T.
Guessing now you maybe meant sprockets. But no SRAM cassette I know of has 53t nevermind a ridiculous jump from 39 to 53. So fuck knows what you're on about?
 

Gary

"S" is for "neo-luddite"
Aug 27, 2002
7,804
5,713
UK
Dunno about anyone else but I'm dying to see this 12speed XX equipped trials bike with 39/53 chainset.
 
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Gary

"S" is for "neo-luddite"
Aug 27, 2002
7,804
5,713
UK
Not sure if your Jubilee clips or fork leg extensions are my favourite
 

englertracing

you owe me a sandwich
Mar 5, 2012
1,588
1,084
La Verne
the non dh rims are pretty thin

Ive bent back a few.

What size? If 27.5 Ive got some bits if you need them
So shit rims, stupid aluminum spokes, annoying hubs, that have alot of drag and poor sealing
And all that adds up to every broke bike persons dream wheels nice.
 

kidwoo

Artisanal Tweet Curator
So shit rims, stupid aluminum spokes, annoying hubs, that have alot of drag and poor sealing
And all that adds up to every broke bike persons dream wheels nice.
LOL

those are some of the lightest strongest, most durable wheels made

Sorry engineering is hard. You do have to run air in your tires and not lap up the tubeless insert nonsense from slow people.

You can thummy down me all you want. I've ridden most wheel setups out there and broken quite a few of them..as in walking out, not being annoyed by a dented rim. A dinged rim wall on an easily rebuilt wheel is nothing once you've knocked out half a wheel of spokes or counted your crushed carbon rims on two hands.
 
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Jm_

sled dog's bollocks
Jan 14, 2002
19,135
9,790
AK
You can thummy down me all you want. I've ridden most wheel setups out there and broken quite a few of them..as in walking out, not being annoyed by a dented rim. A dinged rim wall on an easily rebuilt wheel is nothing once you've knocked out half a wheel of spokes or counted your crushed carbon rims on two hands.
Ok, but have you even been to the Titanic in a carbon fiber sub?
 

Pneuma

Chimp
Nov 5, 2021
61
32
Just fyi, I rode one of those for 5 years like that. It never grew.

Retired the frame after a headtube crack years later

Every one of those frames developed small cracks where yours did. I dont know of a single failure there and dt was honest with me about those.

You can certainly run another bead over it too.

Its a little bit of a design flaw...big rigid cnc part welded to a tube in a heavy load part of the frame. The tube flexes, the machined block doesnt
Thank you for the information.

I have definitely been conditioned to equate a crack in an aluminum frame being the end of its life, as it is challenging to properly repair. On the other hand when I saw that crack I did immediately question its severity and figured a total failure probably wouldn’t end in dentistry.

However, at the beginning of this season I was considering retiring it anyhow as it feels like a kids bike now :(
 

kidwoo

Artisanal Tweet Curator
Thank you for the information.

I have definitely been conditioned to equate a crack in an aluminum frame being the end of its life, as it is challenging to properly repair. On the other hand when I saw that crack I did immediately question its severity and figured a total failure probably wouldn’t end in dentistry.

However, at the beginning of this season I was considering retiring it anyhow as it feels like a kids bike now :(
if you're over the bike, then hang it on a wall (that's where one of mine is :D)

If you keep riding it definitely put some marks on it to track growth. But just know that they all did that.
 

Pneuma

Chimp
Nov 5, 2021
61
32
if you're over the bike, then hang it on a wall (that's where one of mine is :D)

If you keep riding it definitely put some marks on it to track growth. But just know that they all did that.
Yep! It is destined for wall art! It’s the only frame that I have had that is handsome enough for that. The truth is I really like the bike, the suspension is brilliant, it’s fast and super stiff. Buts it’s 1.5” too short and the 26” wheels are punishing on my ageing self. I would love a modernized one, I think. Too bad this isn’t really an option.

With this revelation It’ll get a few more laps this summer, I think. Although my Megatrail was more fun at the bike park than expected.

I’m not sure what I will do about getting a new DH bike together, I am having a hard time justifying the expense for the first time. The 2023 bike glut didn’t seem to impact the DH market and most my shit isn’t compatible moving forward. :tinfoil:
 
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kidwoo

Artisanal Tweet Curator
Yep! It is destined for wall art! It’s the only frame that I have had that is handsome enough for that.
Likewise. I polished mine up and it sits over my workbench.

I’m not sure what I will do about getting a new DH bike together, I am having a hard time justifying the expense for the first time. The 2023 bike glut didn’t seem to impact the DH market and most my shit isn’t compatible moving forward. :tinfoil:
Also likewise.

I just quit and ride dirbikes now because I don't want to give money to anyone but GG. :D

I got sick of every time I got a new frame I need 10 new things to fit some dumb standard no one asked for.
 

Westy

the teste
Nov 22, 2002
54,654
20,484
Sleazattle
this one's kind of a weird spot to do that

so much so that it might be beyond "a pair" and into "failed IQ test"
Obviously a small hole but the radius of even a small hole prevents the stress risers that allow cracks to grow. The risk is not getting the hole aligned properly.
 

kidwoo

Artisanal Tweet Curator
Obviously a small hole but the radius of even a small hole prevents the stress risers that allow cracks to grow. The risk is not getting the hole aligned properly.
just because of the location with regards to frame flex, I'd be terrified of making spider webs

I lucked out with some head tube cracks on both of the ones I owned, so I didn't have to worry about it.
 

Westy

the teste
Nov 22, 2002
54,654
20,484
Sleazattle
just because of the location with regards to frame flex, I'd be terrified of making spider webs

I lucked out with some head tube cracks on both of the ones I owned, so I didn't have to worry about it.
A friend once pointed out a crack completely through my headtube after a long steep and chunky descent. I almost puked.
 

lobsterCT

Monkey
Jun 23, 2015
278
414
Just fyi, I rode one of those for 5 years like that. It never grew.

Retired the frame after a headtube crack years later

Every one of those frames developed small cracks where yours did. I dont know of a single failure there and dt was honest with me about those.

You can certainly run another bead over it too.

Its a little bit of a design flaw...big rigid cnc part welded to a tube in a heavy load part of the frame. The tube flexes, the machined block doesnt
If you weld it, the welding kills the frame's heat treat.

I think it would be hard to come up with a scientific answer to the question of which is stronger - running a bead over that crack assuming the weld is not followed up with heat treatment, or leaving it in the heat treated state, with the crack.


Here is a quick blurb on the rough idea, towards the bottom the author indicates a roughly 40% loss of strength from welding on a heat treated aluminum alloy:

2.1. Aluminum strengthening and welding The basic state of high purity aluminum is an annealed condition that exhibits low yield strength and high ductility. Producing a structural aluminum alloy requires strengthening which typically also reduces the ductility. Strengthening can be achieved by solid solution hardening followed by precipitation hardening and heat treatment for heat-treatable alloys (e.g. 2xxx, 6xxx, 7xxx series) or cold working for work-hardened alloys (e.g. 5xxx series). A typical heat treatment involves heating to 450–530 C (depending on the alloy) followed by quenching to obtain supersaturated solid solution. Quenching can be achieved by cooling in water, oil, air or salt-bath, and it produces high strength and lower ductility material. To improve the ductility and formability, the material is aged at room temperature (i.e. natural aging) or at elevated temperature (i.e. artificial aging). The aging temperature and time depend on the alloy and desired properties. The work-hardened alloys derive their strength primarily from cold working, which is achieved by rolling or tractioning of structural shapes (Mazzolani [13]). Similarly to heat treatment, cold working leads to increased strength and reduced ductility. Heating the aluminum alloy to the temperature of 200–350 C or higher, which occurs during welding, tends to reverse the effects of heat treatment or cold working, returning the alloy to its original state. In the case of non-heat-treatable alloys, this is basically an annealed condition (lower strength and higher ductility). Welding the heat-treatable alloys typically reduces their strength to a level slightly above the annealed condition. This is illustrated in Fig. 1 [7]. Fig. 1 indicates that welding can lead to approximately 20% strength reduction for non-heat-treatable alloys, and almost 40% for heat-treatable alloys. From the point of view of fracture toughness, the strength reduction is often offset by significant increase in ductility. The loss of strength leads to localization of the plastic deformation in the weld and/or HAZ, which has a profound consequence for behavior of welded aluminum structures. As previously noted, similar behavior is observed in martensitic steels

From anecdotal experience, on a homemade al frame, I had it heat treated, but then made some changes to the front triangle with a lot of welding. I didn't re-heat treat the front triangle after modifications, and rode it. It worked for a while, and I avoided the dentist, but it was pretty soft, and eventually got replaced with a new bike when I didn't feel like risking it any more.
 

kidwoo

Artisanal Tweet Curator
If you weld it, the welding kills the frame's heat treat.

I think it would be hard to come up with a scientific answer to the question of which is stronger - running a bead over that crack assuming the weld is not followed up with heat treatment, or leaving it in the heat treated state, with the crack.


Here is a quick blurb on the rough idea, towards the bottom the author indicates a roughly 40% loss of strength from welding on a heat treated aluminum alloy:

2.1. Aluminum strengthening and welding The basic state of high purity aluminum is an annealed condition that exhibits low yield strength and high ductility. Producing a structural aluminum alloy requires strengthening which typically also reduces the ductility. Strengthening can be achieved by solid solution hardening followed by precipitation hardening and heat treatment for heat-treatable alloys (e.g. 2xxx, 6xxx, 7xxx series) or cold working for work-hardened alloys (e.g. 5xxx series). A typical heat treatment involves heating to 450–530 C (depending on the alloy) followed by quenching to obtain supersaturated solid solution. Quenching can be achieved by cooling in water, oil, air or salt-bath, and it produces high strength and lower ductility material. To improve the ductility and formability, the material is aged at room temperature (i.e. natural aging) or at elevated temperature (i.e. artificial aging). The aging temperature and time depend on the alloy and desired properties. The work-hardened alloys derive their strength primarily from cold working, which is achieved by rolling or tractioning of structural shapes (Mazzolani [13]). Similarly to heat treatment, cold working leads to increased strength and reduced ductility. Heating the aluminum alloy to the temperature of 200–350 C or higher, which occurs during welding, tends to reverse the effects of heat treatment or cold working, returning the alloy to its original state. In the case of non-heat-treatable alloys, this is basically an annealed condition (lower strength and higher ductility). Welding the heat-treatable alloys typically reduces their strength to a level slightly above the annealed condition. This is illustrated in Fig. 1 [7]. Fig. 1 indicates that welding can lead to approximately 20% strength reduction for non-heat-treatable alloys, and almost 40% for heat-treatable alloys. From the point of view of fracture toughness, the strength reduction is often offset by significant increase in ductility. The loss of strength leads to localization of the plastic deformation in the weld and/or HAZ, which has a profound consequence for behavior of welded aluminum structures. As previously noted, similar behavior is observed in martensitic steels

From anecdotal experience, on a homemade al frame, I had it heat treated, but then made some changes to the front triangle with a lot of welding. I didn't re-heat treat the front triangle after modifications, and rode it. It worked for a while, and I avoided the dentist, but it was pretty soft, and eventually got replaced with a new bike when I didn't feel like risking it any more.

You can heat treat them again ya know ;)
 

canadmos

Cake Tease
May 29, 2011
20,821
19,908
Canaderp
If you weld it, the welding kills the frame's heat treat.

I think it would be hard to come up with a scientific answer to the question of which is stronger - running a bead over that crack assuming the weld is not followed up with heat treatment, or leaving it in the heat treated state, with the crack.


Here is a quick blurb on the rough idea, towards the bottom the author indicates a roughly 40% loss of strength from welding on a heat treated aluminum alloy:

2.1. Aluminum strengthening and welding The basic state of high purity aluminum is an annealed condition that exhibits low yield strength and high ductility. Producing a structural aluminum alloy requires strengthening which typically also reduces the ductility. Strengthening can be achieved by solid solution hardening followed by precipitation hardening and heat treatment for heat-treatable alloys (e.g. 2xxx, 6xxx, 7xxx series) or cold working for work-hardened alloys (e.g. 5xxx series). A typical heat treatment involves heating to 450–530 C (depending on the alloy) followed by quenching to obtain supersaturated solid solution. Quenching can be achieved by cooling in water, oil, air or salt-bath, and it produces high strength and lower ductility material. To improve the ductility and formability, the material is aged at room temperature (i.e. natural aging) or at elevated temperature (i.e. artificial aging). The aging temperature and time depend on the alloy and desired properties. The work-hardened alloys derive their strength primarily from cold working, which is achieved by rolling or tractioning of structural shapes (Mazzolani [13]). Similarly to heat treatment, cold working leads to increased strength and reduced ductility. Heating the aluminum alloy to the temperature of 200–350 C or higher, which occurs during welding, tends to reverse the effects of heat treatment or cold working, returning the alloy to its original state. In the case of non-heat-treatable alloys, this is basically an annealed condition (lower strength and higher ductility). Welding the heat-treatable alloys typically reduces their strength to a level slightly above the annealed condition. This is illustrated in Fig. 1 [7]. Fig. 1 indicates that welding can lead to approximately 20% strength reduction for non-heat-treatable alloys, and almost 40% for heat-treatable alloys. From the point of view of fracture toughness, the strength reduction is often offset by significant increase in ductility. The loss of strength leads to localization of the plastic deformation in the weld and/or HAZ, which has a profound consequence for behavior of welded aluminum structures. As previously noted, similar behavior is observed in martensitic steels

From anecdotal experience, on a homemade al frame, I had it heat treated, but then made some changes to the front triangle with a lot of welding. I didn't re-heat treat the front triangle after modifications, and rode it. It worked for a while, and I avoided the dentist, but it was pretty soft, and eventually got replaced with a new bike when I didn't feel like risking it any more.
I mean you already know, but one of my old Banshee frames (7005 T6) cracked on the welds on the gussets at the bottom of the downtube. Took it to work and they slid it off to their precision aluminum welder.


It cracked again on the next ride. I stopped riding that frame after that. :brows: :busted:

I also had one of those Turner DHR dw frames, which didn't crack. Though I did have it re-powder coated midway through owning it and that stuff was thicccccccccc, so maybe it was hiding under that? The cnc'd upper link did crack and start to split in half, though. Dave sent me a new one for free.

Had another buddy who cracked a similar frame, but he did what kidwoo suggested and marked the crack and then rode it for another month - it didn't change. I'm guessing there would really only be two outcomes; a) the crack slowly grows, even if not perceivable to the eye or b) it suddenly folds on a severe g-out or something. a) would eventually lead to b).
 

Jm_

sled dog's bollocks
Jan 14, 2002
19,135
9,790
AK
Its proven, holes stop cracks. If crack continues, drill moar holes.