Hello,

This is a model 2000 Trek 5200. I have read on other threads that there was a paint craking issue with early OCLV Treks. There seems to be a great deal of bubbling of the paint in various areas on this one. Mostly near aluminum that is on the frame. The pictures of the BB show a bunch of corrosion near the bottom. A little WD40 and a rag removed all the corrosion and revealed bare aluminum as shown in the other BB pictures below, though some bubbling remained on the carbon part. The other 3 pictures are of the top tube and the cable guides that are attached. The guides are obviously aluminum and have some surface corrosion that has caused the paint to flake away. However and it is hard to see in the pics the paint near the guides is bubbled up around them. Looks like car paint when it is rusting underneath. I don't have a pic handy but it is the same around the front derailleur. Does this indicate a problem with the frame or is it just the paint going to hell? I don't see any dings or scrapes just this bubbling.

thoughts?

Chris

i may be going out on a limb here but i believe unlike iron rust, which is colored and disfigures the metal, aluminum 'rust' (aluminum oxide) forms a clear protective coating. the process stops as the metal is coated and technically makes the surface more durable than before. since you stated its got no other structural damage, i say get it.

yes alum will "rust" ... Pure alum is almost worthless as a metal too soft .. I am almost sure that trek dosen't use the pure alum but a alloy .. alum mixed with other metal and elements to create stronger alum. simmilar to a/c and thier structures.

here is a linkhere is a link to alum corrosion

because for the most part this is a block of alum and not a sheet of alum as used on aircraft skin.

also try this link of the way the US military catgorizes corrosion link
its a adobe file.

With all of this being said the frame sould be inspected b/c its a carbon fiber if you recall the Generation 1 carbon bikes from trek were subject to corrosion inspections. and many of them were replaced b/c it had worked its way into the tubes. I would also read the warrenty that applies to your area on a possible warrenty transfer to second owner ect.

To be honest all I can see is paint missing and exposed alum doing what exposed alum dose. becoming dull and forming a film of powder.

If I were buying this bike I would have have it inspected by a trek rep or a reputable shop with knowlege of fiber bikes. to get their take on what is going on with it. ... I would also have the bottom bracket pulled and inspected. if every thing is ok.

take some sos pads. green scrubbie things you uses with your dishes. They come in several grits get the lightest and a few other up from that. Go at it slow with the lightest and work your way up then back to the lightest should pollish up ok ...and clean the area and repaint with clear or color and keep the bike clean I feel the lug is messed up due to sweat or salt water getting at it. this is why it needs to be resealed. A good coat of wax could also help you out here also I keep all of my bikes waxed up so much so it slipped out of my hand and dropped it and put a scrach on it (oh well). I spend extra time with the wax in chipped areas and such.

unless its spreading like in the first picture you should have a few years.

all in all have it inspected by a copentent shop who deals with trek. unless he is selling it cheap enuf it dosent matter then ride the crap out of it untill it cracks out.


have fun.
Kelsey

as far as the oxide clear protective coating .. not exactly it a white power coating that slowely eats away at the metal and pits it.

You may have a couple of different things going on. Aluminum corrosion on cranks and cable guides is usually the result of sweat. It's also common to have some paint bubbling in the areas where aluminum parts are bonded to the carbon fiber. I have some of each on my 1998 Trek 5500. It's not good but with my bike I'm not too concerned with the integraty of the frame. I do know of an older 5500 that was bad enough that the brake cable guide came loose from the frame. In the case of the bike in the pictures I would say that it's bad enough to devalue the bike quite a bit, in other words I would not pay a lot for it because it's not going to get any better.
There may be bigger considerations however, like does it fit the buyer well?

Al

Thanks Al1943 and others.


Al1943 have you reason to believe there is a compromise to your frame? Has there been more of an issue with this than the cable guides pulling off?.

I'm leary of going to my LBS for an opinion as Australia is not customer service orientated as it is there in the states. Questions about new bikes are answered immediately but anything about older stuff or repairs (other than have the shop fix it) gets a mighty cold shoulder lol.

Cheers

Chris

I've been hanging around these bike forums for several years and I haven't heard of any Trek OCLV failing from corrosion. There were some cracking issues with earlier OCLV Treks including frame failures. I haven't seen the bike in question so would hesitate to say it is OK. Treks have a good reputation for durability as well as customer service. However, I doubt that the warranty will transfer to a new owner. And I doubt that Trek would consider the corrosion as a warranty issue, but I could be wrong. Regardless, I think Trek would re-paint the bike for about $300 U.S. plus shipping, based on what I've heard from others. Biggest problem I have with Treks is that they are hard to fit to riders with long legs or short torsos. I'm one of those.
It's really hard to evaluate a used bike without seeing it. I would almost expect it to need a new chain, new shift cables, cable housings, new tires.... just guessing.

Al