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?

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.

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.

Only carbon asplodes.

Asplode, is that like "aks me"?

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.

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.

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.

https://cimg4.ibsrv.net/gimg/bikefor...7ad626fa80.jpg

One of my favorites bikes--a mid 70s Peugeot PR10--has 2 small dings. They don't bother me.

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.

I think silver bearing solder is appropriate for a a non structural repair. At least that's what I'm going to use.

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.

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.

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.

That works as well but powder coat does not stick to bondo. I definitely would have done this if I was going to paint.

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.

https://cimg3.ibsrv.net/gimg/bikefor...53047fb8ed.jpg

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?

Dents in the Top Tube

it's like Marvin Zindler's ...

https://quixoteugly.files.wordpress....3438366_n1.jpg

[shoutout to my old Houston peeps]

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.

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.