Dents in the top tube
#1
Not lost wanderer.
Thread Starter
Join Date: Jan 2013
Location: Lititz, Pa
Posts: 3,325
Bikes: In USA; 73 Raleigh Super Course dingle speed, 72 Raleigh Gran Sport SS, 72 Geoffry Butler, 81 Centurion Pro-Tour, 74 Gugie Grandier Sportier
Mentioned: 72 Post(s)
Tagged: 0 Thread(s)
Quoted: 885 Post(s)
Liked 989 Times
in
521 Posts
Dents in the top tube
What is the deal, will a bike asplode or something? I have a old Zunow with a few small dents in the top tube.
Has anybody had a frame fold up on them or something?
Has anybody had a frame fold up on them or something?
__________________
Cambodia bikes, Bridgestone SRAM 2 speed, 2012 Fuji Stratos...
Cambodia bikes, Bridgestone SRAM 2 speed, 2012 Fuji Stratos...
#2
Senior Member
Join Date: Nov 2010
Posts: 3,504
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 586 Post(s)
Liked 612 Times
in
447 Posts
Why are you asking? Did you see a post about dents? I think it depends on a lot of factors. Dents to someone might be dings to another. In other words, all dents are not created equal. Is the dent large or small? Is the dent a rounded affair or is there a "crease" in the metal? Is this a super high end SLX with quadruple butting and super thin tubing?
Straight gauge cromo could probably be bent in half and still be OK to ride. I'm exaggerating to make a point.
Personally I would never buy a vintage bike with a dent in the tubing, simply because unless I'm planning on repainting it, it would drive me crazy. If I did buy it, the size, location of the dent, etc. would dictate whether I would have it rolled out or just filled and painted.
I bought a Raleigh once because the saddle on it was worth more than what I paid. I put a different saddle on it and flipped it. The buyer was told that there was a small dent on the top tube and he didn't care a whit. He said it would have more next week because he wasn't particularly careful when locking his bikes up.
Bikes don't typically asplode in my experience, but when or if they do, there is surely a good reason for it.
Straight gauge cromo could probably be bent in half and still be OK to ride. I'm exaggerating to make a point.
Personally I would never buy a vintage bike with a dent in the tubing, simply because unless I'm planning on repainting it, it would drive me crazy. If I did buy it, the size, location of the dent, etc. would dictate whether I would have it rolled out or just filled and painted.
I bought a Raleigh once because the saddle on it was worth more than what I paid. I put a different saddle on it and flipped it. The buyer was told that there was a small dent on the top tube and he didn't care a whit. He said it would have more next week because he wasn't particularly careful when locking his bikes up.
Bikes don't typically asplode in my experience, but when or if they do, there is surely a good reason for it.
#3
Senior Member
Join Date: Dec 2014
Location: Central Virginia
Posts: 4,778
Bikes: Numerous
Mentioned: 150 Post(s)
Tagged: 0 Thread(s)
Quoted: 1676 Post(s)
Liked 3,089 Times
in
911 Posts
In general, small dents, not a problem other than aesthetics. I have two bikes with top tube dents and they are fine. Indications, in my book, of problematic dents are those that cause the tube to deviate from a straight line, dents on both sides (maybe more accurately dent on one side, buckle on the other) or a bigger one that approaches half the circumference of the tube. Most dents are from the bike falling against something or something falling against it, or the “handlebar kiss”. Crash dents are a different beast and usually present a problem.
__________________
N = '96 Colnago C40, '04 Wilier Alpe D'Huez, '10 Colnago EPS, '85 Merckx Pro, '89 Merckx Century, '86 Tommasini Professional, '04 Teschner Aero FX Pro, '05 Alan Carbon Cross, '86 De Rosa Professional, '82 Colnago Super, '95 Gios Compact Pro, '95 Carrera Zeus, '84 Basso Gap, ‘89 Cinelli Supercorsa, ‘83 Bianchi Specialissima, ‘VO Randonneur, Ritchey Breakaway Steel, '84 Paletti Super Prestige, Heron Randonneur
N = '96 Colnago C40, '04 Wilier Alpe D'Huez, '10 Colnago EPS, '85 Merckx Pro, '89 Merckx Century, '86 Tommasini Professional, '04 Teschner Aero FX Pro, '05 Alan Carbon Cross, '86 De Rosa Professional, '82 Colnago Super, '95 Gios Compact Pro, '95 Carrera Zeus, '84 Basso Gap, ‘89 Cinelli Supercorsa, ‘83 Bianchi Specialissima, ‘VO Randonneur, Ritchey Breakaway Steel, '84 Paletti Super Prestige, Heron Randonneur
#4
Senior Member
Join Date: Apr 2007
Location: Thunder Bay, Ontario, Canada - burrrrr!
Posts: 11,674
Bikes: 1958 Rabeneick 120D, 1968 Legnano Gran Premio, 196? Torpado Professional, 2000 Marinoni Piuma
Mentioned: 210 Post(s)
Tagged: 0 Thread(s)
Quoted: 1372 Post(s)
Likes: 0
Liked 1,751 Times
in
938 Posts
For me, simply put, a dented frame or fork has little appeal to me, as a collector. As a rider, a dent or two means little to the structural integrity of the frame. A dented fork, on the other hand my cause me some user concern.
__________________
"98% of the bikes I buy are projects".
"98% of the bikes I buy are projects".
#5
If I own it, I ride it
Join Date: Nov 2005
Location: Cardinal Country
Posts: 5,580
Bikes: Lejeune(14), Raleigh, Raysport, Jan De Reus, Gazelle, Masi, B. Carré(4), Springfield, Greg Lemond, Andre Bertin, Schwinn Paramount
Mentioned: 56 Post(s)
Tagged: 0 Thread(s)
Quoted: 591 Post(s)
Likes: 0
Liked 662 Times
in
311 Posts
#6
Mother Nature's Son
Join Date: Mar 2016
Location: Sussex County, Delaware
Posts: 3,113
Bikes: 2014 Orbea Avant MD30, 2004 Airborne Zeppelin TI, 2003 Lemond Poprad, 2001 Lemond Tourmalet, 2014? Soma Smoothie
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 853 Post(s)
Liked 1,434 Times
in
816 Posts
Asplode, is that like "aks me"?
#7
Senior Member
Join Date: Mar 2013
Location: Maryland
Posts: 3,799
Bikes: Lots of English 3-speeds, a couple of old road bikes, 3 mountain bikes, 1 hybrid, and a couple of mash-ups
Mentioned: 53 Post(s)
Tagged: 0 Thread(s)
Quoted: 887 Post(s)
Liked 335 Times
in
225 Posts
I have a Peugeot PH501 with a lightly dented top tube. I ride it, but when I wash it I can feel the dent and that bothers me for some reason.
#8
Senior Member
Join Date: Sep 2005
Location: Hervey Bay, Qld, Australia.
Posts: 2,928
Bikes: Colnago (82, 85, 89, 90, 91, 96, 03), 85 Cinelli, 90 Rossin, 83 Alan, 82 Bianchi, 78 Fountain, 2 x Pinarello, Malvern Star (37), Hillman (70's), 80's Beretto Lo-Pro Track, 80's Kenevans Lo-Pro, Columbus Max (95), DeGrandi (80's) Track.
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 179 Post(s)
Liked 198 Times
in
124 Posts
I know you're not asking how to fix the dents but small dents can be repaired with bodyfiller and a file to bring it back to round but the best way to fill the hole is to remove the paint from the area and bronze fill the dent but this takes some nerve and skill so a hole isn't blown into the tube with the 'Oxy' torch. Either way, the tube will need re-painting.
Last edited by Gary Fountain; 02-14-19 at 09:07 PM.
#9
Ride, Wrench, Swap, Race
Join Date: Jan 2010
Location: Northern California
Posts: 9,193
Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
Mentioned: 132 Post(s)
Tagged: 0 Thread(s)
Quoted: 1565 Post(s)
Liked 1,295 Times
in
865 Posts
Since these dents are usually only ever noticed by the owner, I try to remember to just laugh at the dents, reminding myself that the dent was probably why I was able to find the bike on the market at a very fair price.
Same goes for scratched paint, mis-matched wheels, etc.
I decorated the sides of the toptube on my "rough stuff" Miyata Six-Ten with handlebar finishing tape, covering all sorts of insults that seemed to be concentrated there.
Note also that I was able to buy this bike for just $24.95 when it was still in a somewhat haggard-looking state.
Same goes for scratched paint, mis-matched wheels, etc.
I decorated the sides of the toptube on my "rough stuff" Miyata Six-Ten with handlebar finishing tape, covering all sorts of insults that seemed to be concentrated there.
Note also that I was able to buy this bike for just $24.95 when it was still in a somewhat haggard-looking state.
#10
Senior Member
Join Date: Apr 2012
Location: Middle Earth (aka IA)
Posts: 20,435
Bikes: A bunch of old bikes and a few new ones
Mentioned: 178 Post(s)
Tagged: 0 Thread(s)
Quoted: 5888 Post(s)
Liked 3,471 Times
in
2,079 Posts
One of my favorites bikes--a mid 70s Peugeot PR10--has 2 small dings. They don't bother me.
#11
Senior Member
It's highly unlikely to asplode. Minor dents on a top tube are usually cosmetic, and can usually be ignored - if you can. I wouldn't absolutely rule out possible failure if the dent(s) is sharp or large, and/or if the frame is made from some type of hard and brittle thin wall tubing. Never hurts to regularly inspect your bike frames for cracks regardless of condition.
BITD we used to roll TT dents out with some sort of contraption that in retrospect i think was a modified pipe cutter. Apparently no one has seen one of these except me... These days you can get the Bicycle Research tube rolling blocks to do the same thing, but they will ruin the paint.
Most TT failures I have seen were in frames that had internal 'aero' cabling. Stress risers originated at the holes.
BITD we used to roll TT dents out with some sort of contraption that in retrospect i think was a modified pipe cutter. Apparently no one has seen one of these except me... These days you can get the Bicycle Research tube rolling blocks to do the same thing, but they will ruin the paint.
Most TT failures I have seen were in frames that had internal 'aero' cabling. Stress risers originated at the holes.
#12
Senior Member
Join Date: Sep 2017
Location: Eastern Shore, MD
Posts: 2,107
Bikes: Road ready: 1993 Koga Miyata City Liner Touring Hybrid, 1989 Centurion Sport DLX, "I Blame GP" Bridgestone CB-1. Projects: Yea, I got a problem....
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 753 Post(s)
Liked 737 Times
in
422 Posts
I know you're not asking how to fix the dents but small dents can be repaired with bodyfiller and a file to bring it back to round but the best way to fill the hole is to remove the paint from the area and bronze fill the dent but this takes some nerve and skill so a hole isn't blown into the tube with the 'Oxy' torch. Either way, the tube will need re-painting.
I think silver bearing solder is appropriate for a a non structural repair. At least that's what I'm going to use.
#13
Bianchi Goddess
Join Date: Apr 2009
Location: Shady Pines Retirement Fort Wayne, In
Posts: 27,858
Bikes: Too many to list here check my signature.
Mentioned: 192 Post(s)
Tagged: 2 Thread(s)
Quoted: 2930 Post(s)
Liked 2,923 Times
in
1,491 Posts
My beloved '87 Sport SX had a small dent in the TT, which I forget where/when it happened, but I still rode it hard with no ill effects. Now the broken stay cap/tube was a different story.
__________________
“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk
“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk
#14
Designer
Join Date: Aug 2005
Posts: 1,368
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
My Cilo has a number of scratches on the frame and road rash on components but it’s that one small dent in the top tube that is extra hard to look at.
But although annoying, I don’t worry about it.
But although annoying, I don’t worry about it.
#15
Senior Member
Join Date: Oct 2013
Location: Great White North
Posts: 926
Bikes: I have a few
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 340 Post(s)
Liked 210 Times
in
104 Posts
I did this to a Jackson I am rebuilding right now. Silver brazing the dings and filing them smooth. I did this because I am getting it powder coated and this seemed to me the best option. I know if I didn’t the dings sure would have bugged me.
#16
Senior Member
I created my dings on the top tube from a crash....(handlebar hit the top tube). That was over 20 years and many miles ago. No asplosions. When I had it repainted they did a good job of repairing the dings to the point where I do not notice them.
#17
Senior Member
Join Date: Sep 2017
Location: Eastern Shore, MD
Posts: 2,107
Bikes: Road ready: 1993 Koga Miyata City Liner Touring Hybrid, 1989 Centurion Sport DLX, "I Blame GP" Bridgestone CB-1. Projects: Yea, I got a problem....
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 753 Post(s)
Liked 737 Times
in
422 Posts
Both the the dinged bikes I have are black, and rattle can-able, but Bondo has always seemed like a temporary patch to put on a machine that may well be around for another 30 years.
#18
Senior Member
Join Date: Aug 2013
Location: San Francisco
Posts: 833
Bikes: '68 Raleigh Suberbe, '92 (German) Centurion Equipe, '85 Schwinn Peloton, 1983ish Zunow Road Racer project, '69 Squanch Super Tourer, 1980 Bianchi Super Corsa, '82 Austro-Daimler Vent Noir, '89 Miyata 914 project, 1982ish Bianchi Rallye
Mentioned: 25 Post(s)
Tagged: 0 Thread(s)
Quoted: 294 Post(s)
Liked 9 Times
in
9 Posts
I have a nice bike with a ding in the top tube that only bugs me when some asswipe (usually family member) points it out. "Hey, there's a little dent there . . . "
STFU
STFU
#19
Senior Member
Join Date: Oct 2013
Location: Great White North
Posts: 926
Bikes: I have a few
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 340 Post(s)
Liked 210 Times
in
104 Posts
That works as well but powder coat does not stick to bondo. I definitely would have done this if I was going to paint.
#20
Junior Member
Yesterday I did buy a high-end super light'n'fluffy used aluminum bicycle with a top tube dent that the original owner regarded as being so bad that I was told he went out and bought himself a new racing bike (In reality I think he just wanted a newer model bike, but I'm not a expert on this stuff.). Apologies for not having a better picture, but the primary dent is still very evident in this section I cropped out of the picture. All of the dents on the bike are on the top tube, and like others many of them are more of what I too would regard as cosmetic dings, but there are just a lot of them and then this bad boy of a dent. Frame seems straight to to me, I gave it a good go over yesterday evening and couldn't find any additional problems, other than the easily remedied "Livestrong" rubber wrist bracelet that was around the seat post which was promptly cut off and now resides in the trash can. So to iterate, question I'm posing to anyone reading this is; was the previous owner correct that this frame is unsafe to ride? Can take and post better pictures of the dents tomorrow if need be.
#21
Senior Member
Join Date: Sep 2015
Location: Madison, WI
Posts: 2,701
Mentioned: 52 Post(s)
Tagged: 0 Thread(s)
Quoted: 1136 Post(s)
Liked 650 Times
in
336 Posts
It looks fine to me. Sort of a big one but unless there are cracks I would just inspect it periodically and ride it. Is the frame straight?
#22
señor miembro
Join Date: Dec 2018
Location: Pac NW
Posts: 6,624
Bikes: '70s - '80s Campagnolo
Mentioned: 92 Post(s)
Tagged: 0 Thread(s)
Quoted: 3883 Post(s)
Liked 6,476 Times
in
3,205 Posts
Dents in the Top Tube
it's like Marvin Zindler's ...
[shoutout to my old Houston peeps]
it's like Marvin Zindler's ...
[shoutout to my old Houston peeps]
#23
Extraordinary Magnitude
Join Date: Aug 2009
Location: Waukesha WI
Posts: 13,646
Bikes: 1978 Trek TX700; 1978/79 Trek 736; 1984 Specialized Stumpjumper Sport; 1984 Schwinn Voyageur SP; 1985 Trek 620; 1985 Trek 720; 1986 Trek 400 Elance; 1987 Schwinn High Sierra; 1990 Miyata 1000LT
Mentioned: 84 Post(s)
Tagged: 0 Thread(s)
Quoted: 2608 Post(s)
Liked 1,699 Times
in
935 Posts
I've got a Columbus SL/SP frame with a dent on the TT. It's just on the edge of my peripheral vision- so I keep catching glimpses of it as I ride= and then it gets me angry all over again.
__________________
*Recipient of the 2006 Time Magazine "Person Of The Year" Award*
Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.
Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.
#24
Senior Member
Join Date: Nov 2004
Posts: 23,223
Mentioned: 654 Post(s)
Tagged: 1 Thread(s)
Quoted: 4722 Post(s)
Likes: 0
Liked 3,036 Times
in
1,874 Posts
The reliability of a dent is a function of the size of the dent, particularly the width and sharpness of any crease. Sharp creases significantly increase the probability of failure. It won't asplode but it may buckle under loads that normally wouldn't affect it. Of course, the thinner the tubing, the more susceptible it is. Frame blocks are a popular shop tool for removing dents because they reduce the size of the dents and crease, reducing the probability of failure, though at the expense of the paint finish.
As an extreme but easily demonstrable example of how a dent impacts the structural strength of a tube, get an undamaged aluminum soda pop can. Try to buckle it by pushing inwards on the ends. Or try bending it. It's not easy to do. However, if you use your thumb to put a small dent with a crease into the side of the can, the loads required to buckle the can drop significantly. Dents have the same effect on a bicycle tube. However, it's very hard to predict the new, reduced load limit. Moderate dents may be fine for everyday use but could cause the tube to buckle under a bigger impact, such as hitting a curb or pothole. It's impossible to predict.
As an extreme but easily demonstrable example of how a dent impacts the structural strength of a tube, get an undamaged aluminum soda pop can. Try to buckle it by pushing inwards on the ends. Or try bending it. It's not easy to do. However, if you use your thumb to put a small dent with a crease into the side of the can, the loads required to buckle the can drop significantly. Dents have the same effect on a bicycle tube. However, it's very hard to predict the new, reduced load limit. Moderate dents may be fine for everyday use but could cause the tube to buckle under a bigger impact, such as hitting a curb or pothole. It's impossible to predict.
#25
Senior Member
Join Date: Sep 2017
Location: Eastern Shore, MD
Posts: 2,107
Bikes: Road ready: 1993 Koga Miyata City Liner Touring Hybrid, 1989 Centurion Sport DLX, "I Blame GP" Bridgestone CB-1. Projects: Yea, I got a problem....
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 753 Post(s)
Liked 737 Times
in
422 Posts
Can a dent in an aluminum tube be rolled out?