Is this frame cracked? Or is it just paint?
03-19-16 | 05:51 PM
#1
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From: Utah
Bikes: '88 Trek 1200, '91 Trek 1400
Is this frame cracked? Or is it just paint?
Hey, noticed these the other day and think it's paint, but thought I'd post up some pics and see what you guys thought. I can barely feel them with my nail and they definitely don't wipe off...
If it matters, the bike is a 91 aluminum trek (bonded frame).
Thanks!
If it matters, the bike is a 91 aluminum trek (bonded frame).
Thanks!
03-19-16 | 06:24 PM
#2
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From: Rochester, NY
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Cracks in metal don't usually have that spider web look like they might in glass. Usually is a single fissure which might wander a bit, but not have parallel additional cracks. You might pull the BB out and look inside the shell. I suspect you see paint not metal issues. Andy.
03-19-16 | 07:29 PM
#3
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From: Utah
Bikes: '88 Trek 1200, '91 Trek 1400
Okay. I looked the bike over and noticed quite a few more that are thinner, but fairly widespread on the bike. This leads me to believe even more that it's probably in the paint.
Not to sound lazy, but is there anyway to be sure without pulling the BB?
Not to sound lazy, but is there anyway to be sure without pulling the BB?
03-19-16 | 08:04 PM
#4
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From: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
My fatalistic do nothing and just ride is based on the location where the related safety issues are minimal. If the cracks were in a more critical area, they'd have to be investigated.
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
03-19-16 | 08:40 PM
#5
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From: City of Brotherly Love
Bikes: Raleigh Companion, Nashbar Touring, Novara DiVano, Trek FX 7.1, Giant Upland
Doesn't look like a crack in aluminum. It could be in the epoxy but without stripping down the paint it's hard to diagnose. Take some high resolution photos and see if there's any change.
Was the rear triangle ever spread?
Was the rear triangle ever spread?
03-19-16 | 08:57 PM
#6
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From: Rochester, NY
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Trek has had an issue with the paint's flexibility, the bonding filler's and the AL's all being somewhat different from each other. Most often the finish cracks develop at the bonding borders as the two AL frame members flex and the filler and paint between and above can't keep up, so to speak. Andy.
03-19-16 | 11:03 PM
#7
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From: Utah
Bikes: '88 Trek 1200, '91 Trek 1400
Bezalel, as far as I know the rear triangle wasn't ever spread. It's spaced at 126mm.
I was planning on doing about 70 miles on it tomorrow and I've been commuting to work on it. Guess if it breaks, it breaks... I love riding this bike so it'd suck if something happened.
I was planning on doing about 70 miles on it tomorrow and I've been commuting to work on it. Guess if it breaks, it breaks... I love riding this bike so it'd suck if something happened.
03-20-16 | 07:25 AM
#8
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From: Dover, NH
Bikes: Indy Fab steel deluxe, Aventon cordoba, S-works stumpy fsr, Masi vincere, Dahon mu uno, Outcast 29 commuter
Mark the ends of the scratch with a sharpie or nail polish, see if it's growing by checking regularly.
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