Kontact

Just the one you quoted.

Are you complaining that he asked, complaining that I answered, or just complaining?

Or is your post an attempt to get rid of extraneous posts by adding your own extraneous and off topic post?

Keep up the good work.

PhilFo 

The whole "same process used in aerospace..." is a great marketing hype. They also use adhesive tape. The one thing that the average cyclist does not do, which A&P techs do for a living, is to inspect and completely rebuild frame components on a frequent and regular basis.

Kontact

However, isolating the carbon from the aluminum with fiberglass is obvious and normal solution to the problem of galvanic corrosion. It isn't just marketing.

PhilFo 

Kontact don’t get the notion that I’m disagreeing with you. Isolating the dissimilar materials is absolutely necessary. What I’m saying is that while “aerospace industry” processes have been used, it does not negate the fact that in the aerospace industry, entire vehicles from the rubber touching the tarmac to the top of the tail are inspected and repaired/replaced very frequently. This is not something that a cyclist is doing regularly, if at all.
As for the hype of “aerospace” in cycling, yes, it is hype used by bicycle manufacturers to make their products seem superior to other technology. The Wright Flyers were made of wood, so that’s “aerospace industry” right? Where are the wooden bicycles? Yes, I know they exist, I’ve built some wheels for early 20th century safety bicycles with wooden rims. My old sneakers had velcro straps and I wanted them because velcro was used by astronauts and that fact was used to market the shoes to me.

Kontact

I wrote an article once about how poor the engineering in cycling actually, so I get you.

However, bikes are really easy to inspect compared to a wing root. The OP inspected his bonds.

fishboat

I didn't read it in any Trek documentation..it was off some forum, possibly BF. In this case, apparently it wasn't marketing hype as Specialized seems to have ignored best-practice at the time and taken the "let's save $.94..by the time it becomes a problem it won't be our problem" pathway.

I don't doubt what you're saying is true(aerospace inspection & rebuild), however your broad generalization doesn't apply here. The point, in this case, is either the mfg did the bonding right or they saved a few cents and ignored what was known at the time as the proper process, regardless of the source of that process. It's likely the aerospace industry did develop the carbon-aluminum bonding process..that doesn't make it hype or a bad process.

PhilFo 

Tough crowd.
I’m not saying these manufacturing processes are bad, nor the products themselves; my point is that the inspection, repair/remediation, and/or replacement go hand-in-hand with the product itself and the replacement or recementing of tubes/lugs is simply not something that is done by all but a handful of cyclists.

Zara Sp00k

I guess this pretty much explains why my two bonded AL/carbon fiber frames do not have this problem.
I was a mechanical engineer for 44 years, I worked with at least 50, if not 100 companies, most were very religious about proper design, a few were not, often it was management that decided they would go against engineering to save a buck. The only time I can remember one of my engineering managers being like that was when I told him we should not mount a PCB upside down, after all, heat rises is pretty basic. Eventually many PCB's were returned, the electrolytic capacitors failing due to excessive heat.

Atlas Shrugged

There is a whole lot of assumptions and judgment going on here with no facts other than a few bike shop urban myths.

Meanwhile the OP is happily riding along and will continue to do so for another decade.

Kontact

I've worked in aviation and the bike industry for decades. You don't know what you're saying.

flipchip

Thanks for all the advice fellas. It's not actually mine, just a bike I was considering purchasing. I've since found a mint 1990 model.

Kontact

That was you takeaway from reading this thread?

wheelreason

We toured the Trek factory back in the early 90s when the OCLVs were first coming out, and got to see the 2000 series frames being bonded, and yes, "aerospace technology" was hyped, in truth, they just used the same adhesives. They did have a batch of them that came undone due to the seats not being returned to their upright position...

flipchip

Yes. I didn't buy the pictured bike, I found a mint model without any signs of corrosion. Given its already lasted 30 years, I figure it'll probably last another couple, and in the meantime I know what to look out for.

So, uh, thanks anyway?

Kontact

I think your assumption that bonding failures with this particular frame only happens with white powder is.... misplaced.

Zara Sp00k

Your statement could lead someone to believe bonded carbon frames are prone to failure, not true. Properly designed and manufactured, it will last as long as any other frame.
It might be a good idea though, to avoid any brand that shows this symptom unless you know for sure they eventually changed their design and process, and then only buy after the date of the change.

Kontact

The only conclusion my comments should lead anyone to is that the Allez Carbon bikes were prone to failure - and they almost all did. We know they weren't built correctly.

Zara Sp00k

that's what you should have said in the previous post, no need to brow beat the guy and leave others confused by what you mean

VtwinVince

I had a '95 Epic Comp for 14 years, until it was stolen. An absolutely fabulous bike that never hinted at failing. Anecdotal? Sure. I also have a '93 Cadex CFR2 which I wouldn't hesitate to flog all day long. Safety is an illusion which our society seems unduly obsessed with these days IMHO.

Schweinhund

I blew apart, not one, but two Raleigh Technium MTB frames from this problem.
I was young then, I cannot imagine what it would feel like now.
Hang it on the wall and treasure your memories

Kontact

Because neither of those frames was defective like the Allez.