got this 1996 kelin quantum II for a good deal, a bit beat up but still pretty.
I’m just wondering on the safety of riding with these dents in the downtube.
The one of the drive side is pretty mild, just a slight indent, on the opposite side same spot is another more prominent ding. Neither seem to show signs of cracking, which makes me feel better. I can’t say i love them both being in the same area of downtube.
If i just keep watch for cracks should I be generally okay? for reference I weigh ~130lbs and ride “hard”
by judz05
11 Comments
It’ll be fine till it isn’t, but don’t worry you’ll see it coming. That’s a very low stress area with lots of other metal on that large diameter tube to hold things up. That tube has very thin walls right there and is hence prone to dings.
You’ll have to make your own judgment on whether its worth the risk.
All aluminium frames will break eventually (and most other materials too), the when could be tomorrow or 200 years from now. It all depends on the load you put on it and how overbuilt it is.
For what its worth I rode an old 26″ aluminium frame to destruction with similar dents in the top tube & bottom tube. What failed was the weld between the seat tube and the BB shell. I’m about 200lb.
It’s fine. The downtube is a tension member so it’s not going to buckle. Those fat tubes are super stiff but as you discovered thin away from the ends.
Oh this thing is totally trash my dude. You should get this to a dumpster ASAP. Like, anyone would be a fool to pull this out of the dumpster and ride it, for sure not safe. But like… just… let me know which dumpster you plan to take it too… just so like… I can make sure no one else takes it you know… because its not safe. What is your zip code also, btw. Just so like, you know I can make sure no one dumpster dives this ~~beauty~~ *cough* I mean death trap.
On a more serious note, this bike is probably fine. Just look out for any cracks, and it should be good to ride for years to come. Super cook bike btw, I’d love to get my hands on one of these. Problem is, I live in an area where this get scooped up super fast, and/or they are expensive.
Cool bike dude. I like the build.
This is not advice, but I’d ride it on the road and I wouldn’t think twice.
That bike is sex
Ride til its a crack then wall mount it driveside out.
Kleins are works of art, and that is no exception. Ride it, like others have said that’s not a high stress area. I wouldn’t ride it down a flight of stairs twice, but you’re only 130lbs so maybe I would :-)
A battle scar on a beautiful bike. Keep an eye on it but that bike needs to be continuously ridden.
With a carbon frame this would be an issue, but steel and alloy can take this with ease…some of my own bike frames and some of my friends have dents much bigger than this since more than ten years without any problems…as long the frame itself isn’t bent from the impact……….
1998 CAAD4 cracked near the seat stay after 20 years. Had a bunch of dents in the top tube that *maybe* contributed to it.
Current aluminum frame has a dent smack bang in the middle of the top tube. Have been riding it for over a decade now. I anticipate a similar crack around the seat or chain stays in time (or whenever I misjudge an massive pot hole). 182lbs, I think you’ll be fine for a while yet.