Bicycle Mechanics - Upper seat tube dented in from repair stand mount

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i n f a m o u s
10-29-12, 11:13 PM
Is it possible for a repair stand mount to dent a seat tube on a chromoly steel frame? I recently purchased a brand new Fuji bike from a LBS and noticed my seat tube was dented in near the upper region because of the mount from a repair stand.
I'm sure its not anything to be worried about but it does bother me because I purchased this bike new and I dislike the fact that my bike was improperly handled.
I called and told them about the indent near the upper region of the seat tube and the person of the phone told me that its impossible for the clamp to make such a dent on a steel frame bicycle. If they're going to deny it was their doing, would Fuji accept my claim?
Here's a picture of the seat tube where it's dented in. Also just to clear any confusion, my bicycle is flipped upside down in this picture.
mrrabbit
10-29-12, 11:18 PM
That's appears to be tapered tubing in the seat cluster area, very often seen on non-lugged frames. Think double-butted inside out.
=8-)
Never really seen anyone clamp a bike that low on the tube for maintenance - or on the seattube at all - always on the (or a crappy replacement) seat post.
jimc101
10-30-12, 01:16 AM
As you purchased it new, how about going back to the shop, and look at another bike of the same model, if this has the same 'dent' then it is how it was made with a tapered tube from the factory.
I don't understand the picture. What are we looking at? I've rotated the picture so that the top tube is on top. Are you talking about the area(s) that I show with arrows?
http://i167.photobucket.com/albums/u143/cale_kat/Kuota%20Ksano/Kinesis%20Decade%20Tripster/IMG_20121029_220453.jpg
Airburst
10-30-12, 06:22 AM
That is almost certainly meant to look like that. Apart from anything else, if the tube had been dented that much, the paint would very likely have cracked and flaked in the area where the actual deformation of the metal took place.
ksisler
10-30-12, 08:49 AM
Bike forums has previous threads about damage from bike repair stands. It is not unheard of.
CACycling
10-30-12, 09:33 AM
If it is dented in that location, the seat post will be locked in place (or, if there is no seat post in place, you will not be able to install one). If you haven't already, check that to verify there is a problem.
reddog3
10-30-12, 09:43 AM
Appears to be external butted tubing. If it was indeed "squashed" from the clamping, you'd have trouble removing or sliding the seat post in the seat tube. I'd be more concerned about the "big" hole drilled in the seat stay.
LarDasse74
10-30-12, 09:45 AM
Repair stand clamps can damage frames. However, there are usually 2 or 4 flat dents, not a perfectly round and consistent taper that continues the length of the tube. What you are looking at is almost certainly a tapered tube - frames often are made with thicker metal at the top of the seat tube so there is enough material to accurately ream out after welding distortion.
fietsbob
10-30-12, 10:02 AM
step 1. put seatpost in.. I've messed up a decal/sticker, nothing more.
Clean rag, frame in loose pressure, repair stand clamp is better.. if no seat post (or it's Carbon)
carbon there is a repair stand seatpost substitute,
the race team pros, dont use a tube clamp stand.
bobotech
10-30-12, 12:45 PM
That looks intentional to me from the manufacturer.
i n f a m o u s
10-30-12, 08:47 PM
Wow! Thanks for the replies and for reassuring me that this wasn't user error.
As you purchased it new, how about going back to the shop, and look at another bike of the same model, if this has the same 'dent' then it is how it was made with a tapered tube from the factory.
I have yet to confirm if my bike has the same dent on the seat tube on another bike at the shop but I will when I have the time. I'm just hoping the 'dented' area is tapered tubing like some members here pointed out.
I don't understand the picture. What are we looking at? I've rotated the picture so that the top tube is on top. Are you talking about the area(s) that I show with arrows?
http://i167.photobucket.com/albums/u143/cale_kat/Kuota%20Ksano/Kinesis%20Decade%20Tripster/IMG_20121029_220453.jpg
Yes, that area you're pointing to. :)
Appears to be external butted tubing. If it was indeed "squashed" from the clamping, you'd have trouble removing or sliding the seat post in the seat tube. I'd be more concerned about the "big" hole drilled in the seat stay.
I can slide my seat post in and out no problem because of the generous amount of grease they applied to the seat post but until I see with my own eyes that my bike was manufactured the way it is, I will be at peace.
What's wrong with the hole near the seat stay? Wasn't that hole purposely drilled out to air out any moisture to prevent rusting? I noticed two more holes near the Chain stay too. I'm guessing they serve the same purpose as well?
mrrabbit
10-30-12, 09:02 PM
During brazing/welding, hot gases inside the tubings need to vent.
=8-)
Old Hammer Boy
10-30-12, 09:29 PM
Those holes are a great entrance point for Frame Saver; a good idea for a steel frame.
Is this, by any chance, a Fuji Feather? Described on the Fuji website as:
FRAME: Elios 2 w/ outer-butted seat tube
Sixty Fiver
10-30-12, 11:31 PM
You can crush a bike in a repair stand but the stand has to be pretty tough and the mechanic has to be really strong and incredibly stupid to try and close a clamp on a tube that is too big for it's setting.
Aluminium frames on the other hand... you don't need to be quite as strong.
Get into some modern steel tubing with extremely thin walls and you can damage a frame much easier than you can with a straight gauge frame.
Sixty Fiver
10-30-12, 11:31 PM
Appears to be external butted tubing. If it was indeed "squashed" from the clamping, you'd have trouble removing or sliding the seat post in the seat tube. I'd be more concerned about the "big" hole drilled in the seat stay.
The holes are for venting gases during welding / brazing.
reddog3
10-31-12, 07:58 AM
"The holes are for venting gases during welding / brazing."
Yes, I know the intention of holes for gas venting. The one in question here seems to be in an odd location and way larger than necessary. On a seat stay under compression it is of no consequence, but odd- just sayin'
I theorize than venting closed end tubes is not necessary. And I'm not the only one who welds tube structures (bike frames, etc) without vent holes.
CACycling
10-31-12, 09:48 AM
I can slide my seat post in and out no problem because of the generous amount of grease they applied to the seat post but until I see with my own eyes that my bike was manufactured the way it is, I will be at peace.
There is very little tolerance in a seat tube/seat post interface. If the area in your picture was a dent and not the way the bike was manufactured, the seat post would not move.
calstar
10-31-12, 10:35 AM
There is very little tolerance in a seat tube/seat post interface. If the area in your picture was a dent and not the way the bike was manufactured, the seat post would not move.
^^^^ Yep.
i n f a m o u s
10-31-12, 11:24 PM
Is this, by any chance, a Fuji Feather? Described on the Fuji website as:
FRAME: Elios 2 w/ outer-butted seat tube
It's actually a 2012 Fuji Classic.
Lol, I didn't pay much attention to the 'outer-butted seat tube' description when I read the specs for my bike. Thanks for saving me time from the bike shop. :)
There is very little tolerance in a seat tube/seat post interface. If the area in your picture was a dent and not the way the bike was manufactured, the seat post would not move.
I can slide my seat post without any problems which is a good indication that my seat tube has not been compromised. Thanks for the tip. :)
Andrew R Stewart
11-01-12, 01:28 PM
"The holes are for venting gases during welding / brazing."
Yes, I know the intention of holes for gas venting. The one in question here seems to be in an odd location and way larger than necessary. On a seat stay under compression it is of no consequence, but odd- just sayin'
I theorize than venting closed end tubes is not necessary. And I'm not the only one who welds tube structures (bike frames, etc) without vent holes.
reddog3- Millions of bikes have these holes. Some larger, some smaller. Usually towards the end of the tube, often in an out of the way/less seen location. It is very uncommon to have said vent hole be the source of a crack or other problem, that's why they're used, because they work REALLY well.
Another reason to have vent holes, and larger then tiny ones, is to allow the builder/manufacturer to rinse out the interior of the frame to remove the flux after joining the tubes. The flux could cause further corrosion and would prevent any rust inhibitor from fully coating the insides.
While there is a debate on the need to keep a tube vented after the building, to close off vents or not, their need during manufacturing is not in question. I have built frames with very well hidded vent holes, completely out of sight after the frame has parts assembled on it, only to be scolded by the painter. The vent holes can weep out stuff that contaminates paint. The painter might not see or remember where the holes are and might not take adequate precautions. Andy.
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