retrogressionage

I am sorry, but any trail that Gee Atherton calls 'spicy' on a 150 mm bike is a no thank you from me...

@Velosexualist: It is ok to strip paint off of an aluminum bike to get the raw look, but make sure that you have someone who knows what they are doing and have it clear coated with a durable finish. Anodized finishes are not like painted frames though...the anodized layer is actually corrosion product (i.e. like oxidation but a different chemical process) and the anodized layer is actually chemically bonded to the aluminum metal (unlike paint)...I would not recommend removing anodize from a frame to give it the raw look because the types of chemicals and/or sanding that you would need to do to completely remove the anodize layer would potentially compromise the tubing and welded areas.

@blueninja: Aluminum possesses a transparent oxide layer that forms instantly in the presence of oxygen. A popular joke within the aluminum industry is that one never truly sees aluminum itself, as there is always a thin oxide layer on its surface. So, when you polish an aluminum component to achieve a shiny appearance, you are reducing the thickness of the structural portion (aluminum) while simultaneously creating a new corrosion layer. While this may not be critical for a robust part like a stem, which typically has ample material, it is not advisable to remove the paint or anodized layer from an aluminum tube located near a weld. Aluminum tubing is often thinner and larger in diameter compared to other metal tubing to provide stiffness and save weight. Welding aluminum without compromising its heat treatment (or temper) is challenging, resulting in welded areas having lower ductility than the parent aluminum alloy. By removing the anodized layer and allowing new oxide to form, there is a possibility that the fresh oxide might develop within existing micro-cracks near the weld or beneath a welding fillet. Oxides have a greater volume (lower density) than the parent metal. Consequently, when oxides form, they can exert stress by wedging themselves within cracks or under welding fillets, leading to gradual crack propagation. As the crack propogates, new oxide forms at the crack tip, creating further wedging stresses. In the presence of an electrolyte (such as water and salt, like road salt or sweat), this oxide wedging process accelerates due to the low cycle fatigue that occurs during bike riding. While it may take several years for a crack to propagate and cause failure, the risk is undeniably present. One issue with aluminum is its high specific modulus, which refers to its stiffness relative to its density. Aluminum is exceptionally stiff per unit volume compared to other metals, making it advantageous for bike frame design. However, when aluminum frames fail, they often fail catastrophically due to their lower ductility, and welded areas are particularly susceptible due to the compromised heat treatment. In contrast, materials like steel or titanium, with lower specific moduli, exhibit more ductility and tend to deform before failing, providing visual indications of impending failure. When an aluminum bike is manufactured properly, with careful welding and robust anodizing or paint coatings, there should be no issues. However, I strongly advise against removing the paint or anodized layer from an aluminum component or frame, as it increases the risk of accelerated crack growth and potential failure.

As a metallurgist....I can't listen after someone jokes about stripping anodize off of aluminum...do not strip anodize off of aluminum parts unless you want catastrophic corrosion cracking failures at some undetermined and unexpected point during a ride...ughgh

@Po1nt2009: Dude if you miss Interbike, then you must remember the custom painted frame / fork and all of Tyler's matching anodized bling that he took to Interbike one year...that bike was sweet...can't remember what it was now, maybe an Intense? I used to ride with those guys when they came through town back in the day...

Love this...I still have three sets of 26 pedals on my bike and I also put them on my boy's bikes now that they are old enough to have a bit of bling! Tyler is the man!

Every year this thing seems to get scarier...I don't really know how DH can progress much beyond this...it really has to be the limit of what humans / bikes are capable of...if we start pushing much beyond this I think the risk to the riders is just too significant...looking forward to watching though!

I am sorry, but that stash...Mr. Vergier...either grow it out and get fancy or consider letting it go...

@Corinthian: that was an awesome comment...huge Killers fan and now I can't stop laughing my ass off....thank you for that!

Bar ends...seriously...what is wrong with this guy :)