Top tube rust control and paint crawl

potterac

New member
I own an '89 Wicked that is starting to show rust and paint crawl on the top tube. Chris Chance himself has said that there is an issue with top tubes rusting from the inside out. When these frames were made, the vent holes were filled on the inside of the frame in an effort to keep moisture out, but in fact it keeps moisture in. Has anyone drilled holes on the inside of the frame to allow air to pass through the top tube and prevent a moisture issue? Would this affect the value?
Best of Luck,
Potterac
 

colker

Active member
Wickeds are not particularly valuable and the mod you pretend enhances value imho. Otoh, a rusted out wicked has even less value, as in zero value.
 

I-ROBOT

Active member
I would be very surprised to see a top tube rusting from the inside out. In fact, i would say it's nearly impossible since there are no vent holes in either the head tube or the seat tube. If there is moisture inside the top tube, it is there from the day it was welded.

I suppose there is a small chance (pun) that a tube could corrode from the inside, but it is far more likely that any corrosion is starting on the outside and working its way in.

One common issue with 4130 chrome-moly tubing is that the heat-affected zones immediately adjacent to the welds are much more susceptible to corrosion than other areas of the tube or the welds themselves.

Since the top tubes are butted, I would think the thin areas of the middle of the tube would be more likely to corrode through from the inside.

I'm not sure about what Chris has said without seeing the actual quote or statement regarding the issue.

But i will go on record to state that head tubes and seat tubes were NOT drilled for venting. We would leave a very short section unwelded during the main triangle welding process and when the top tube welds had cooled enough, the short section could be welded without fear of blowing out the weld bead from internal air expanding from the heat of welding.

This would also apply to the downtubes. Early models did not have sealed water bottle bosses and those were entry point for moisture and there was no easy way to remove it once it got in and that did create some problems. I distinctly remember replacing several downtubes on early bikes that rusted through at the bottom of the bottom bracket joint

Hope this helps
Scott
 

potterac

New member
Scott,

Thank you so much for your response, I'm honored to have an ex-FAT City Cycles employee answer back.

It's always great to hear a first hand account and learn more about the process of making these amazing bikes.

I would really like to see the inside of a sealed top tube some day. Has anyone out there had a 'chance' to see how these frames are holding up internally?

My reference to Chris Chance speaking about cutting tubes apart and finding rust was from a seminar at the Philly Bike Expo a few years ago. He gave an interesting presentation about the history of FAT City Cycles. Later, there was a 'chance' to ask questions and this topic came up. My memory recalls him talking about the top tubes, but maybe I miss-heard and he was talking about the issue with downtubes.

For now, I have moved my bike to another location and will keep a close eye on the paint degradation and rust spots.

Thanks again,
Potterac
 
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