Mountain Biking - ball bearing in top tube?

A few days ago I began to hear a rattling from the frame every time I braked hard, then again when I restarted. Some investigation and shaking of the bike upside down revealed a ball bearing was rolling around in my top tube. I can't think of where this would have come from, is it possible it was just dropped during the build, or should I be worried?

Thanks

It's a petrified Chinese welder mouse. They train the little buggers and send them inside frames to do the high-risk confined-space work in areas too small/deep to get TIG electrodes into. Every now and then, they forget the little guys are in there, add the seat tube and button 'em up before anyone knows what happened. He probably partially decomposed and stuck to the inside of your top tube, only to be jarred loose and set free to roll around in there at the first big bump. Look for the reamains of tiny welding leads coming out from the bottom headset cup -- a telltale sign there was a welder mouse at work.

http://www.cyberweld.com/images/logo.gif

It's a petrified Chinese welder mouse. They train the little buggers and send them inside frames to do the high-risk confined-space work in areas too small/deep to get TIG electrodes into. Every now and then, they forget the little guys are in there, add the seat tube and button 'em up before anyone knows what happened. He probably partially decomposed and stuck to the inside of your top tube, only to be jarred loose and set free to roll around in there at the first big bump. Look for the reamains of tiny welding leads coming out from the bottom headset cup -- a telltale sign there was a welder mouse at work.

http://www.cyberweld.com/images/logo.gif

Is that true?

Yes, I have heard of that before, it is True mice welders are sacrificed to build Mtn. Bikes. And Yes you should be worried.

Please, people. I wouldn't be worried about a ball bearing in my top tube, but it would annoy me. Generally, top tubes are not sealed, there are holes on the ends that connect to the seat tube and head tube. I'd take the seat post out and try to work the bearing into the seat tube (there'll be a lip to get over). Once it's in the seat tube, you should be able to roll it out. If it's not a steel frame you can try to use a magnet to manipulate the bearing. Never had anything stuck in my frame before, and it sounds like it'd be a pain in the butt to get out. Good luck if you try.

A few days ago I began to hear a rattling from the frame every time I braked hard, then again when I restarted. Some investigation and shaking of the bike upside down revealed a ball bearing was rolling around in my top tube. I can't think of where this would have come from, is it possible it was just dropped during the build, or should I be worried?

Thanks

It doesn't bother you, does it?

oh, i got it out alright, albeit using very creative methods, i'm just wondering if it could be from something important

probably just the headset

i mean is that an issue, if a ball bearing is falling off my headset...

i don't know whether to believe you or not pete
"small and round and made of metal" leads you to the definitive judgment that its from the "fetzer joint" or the "transverse weld"
can anyone corroborate this diagnosis?

1. Yes it is round (a ball bearing)
2. Yes it is made out of metal, though I couldn't tell you what kind, or if it's magnetic etc.
3. Small is a relative term, although I would say what I found is probably ~2mm in diameter

My guess is that the metal piece came out of the henweigh.

because...
its about 2 weeks old so in a little bit i'll be taking it back to the lbs for its checkup so i figured i would just ask them about it

p.s. pete your birthday is april 2002? making you all of 5 years old?

whats a henweigh?
...about 2 pounds

haha

i try

but back to the issue at hand, since you seem to know a lot can you please explain what you think happened

damn are you aggravating

what is a fetzer joint, other than being on the lower head tube weld

if a ball bearing from my headset ended up inside my top tube, does that mean the headset needs to be reassembled?

"Hum daddy bow-wow."

Is that true?Who do you think did the welding inside the old aluminum canteens, in the days before Nalgene bottles? It was always understandable to find odd-colored stains inside the ones you picked up off the shelf at the Army surplus store; but you really had to watch it if stuff like that was inside a new one.

oh, i got it out alright, albeit using very creative methods, i'm just wondering if it could be from something important

How creative did you need to get to remove the stray BB? shouldn't it have rolled right out of the seat tube if you stood your bike vertically and removed the seat post?

At the bike shop I go to, one of the mechanics played a trick on one of the other mechanics once and stuck a ball bearing inside his rim (double walled... so it just rolled around and made noise). Sounds like you are a victim of a similar prank.

haha, at our bike shop, we dont have a whole lot of space, and when someone leaves their personal bike in an annoying spot, we prank them...I've have my high end road bike "reflectored" with about 50 reflectors and bells before.

one good prank that we did to my friend Paul was to take the tire off of his wheel, cut a small hole in the tube and drop a ball bearing in the tube. The tube was then patched up, reinstalled in the wheel, and inflated again. two days later, paul comes in complaining that he's got this damn rattleing noise from the front wheel! I wonder what it was?

I'm putting ball bearings in all friends bikes I work on from now on. Too cheap to take it to a shop? Your bike is now self-annealing.

haha, at our bike shop, we dont have a whole lot of space, and when someone leaves their personal bike in an annoying spot, we prank them...I've have my high end road bike "reflectored" with about 50 reflectors and bells before.

Haha. I've had a ball bearing put in my handlebars and my bike covered in J+B's touch up stickers for kids' bikes.

How creative did you need to get to remove the stray BB? shouldn't it have rolled right out of the seat tube if you stood your bike vertically and removed the seat post?

i thought so, but the hole that empties the top tube into the seat post tube is not the diameter of the top tube, but only about 1/2 an inch in diameter. it's also not seated at the bottom of the tube but in the middle so the bearing didn't roll right out.

Is that true?

No it's not true. His bike must have gotten mixed up with Richard Gere's.