(05-27-2013, 12:36 AM)holdennb Wrote: Hi all,
I'm new to bike maintenance, and I just got an old 12-speed with a threaded headset. I wanted to raise the stem, so I loosened the top bolt, and tapped it with a wooden block, as I've read about.
Unfortunately, it seemed to be stuck, so I hit it some more, but then the bolt just fell right through, as if there were no threads. Now the bolt is just loose, and I have no way to tighten it, and the stem is still stuck. Have I done something horribly wrong? Help!
Thanks in advance
Sounds like your stem is either rusted or galvanized to the fork.
If your quill stem is aluminum it's more likely galvanized to the steel fork. This normally happens if enough water or moisture gets between the fork and stem especially in the rain. If your stem is not properly greased when inserted into the fork, it will fuse to the fork over time if moisture and water gets in there.
You can verify to check if the stem is steel buy using a magnet.
If the stem is steel, then WD-40 could work for you, but it's a bit weak, but better yet LiquidWrench Penetrating oil.
However, If your stem is aluminum, any of the above I mentioned won't do a thing for aluminum oxide when it bonds/fuses to the steel..and galvanizes to the steel. This bond that it creates gets so strong to the point that it's near impossible to get off by brute force.
At this point for aluminum stems, you can get 2 liter bottle of Coke/Pepsi and flip the bike upside down.. get some kind of silicon sealant that's not strong like some kind of household silicon sealant that's safe for aquarium use... plug up the bolt hole and any part that might allow stuff to leak out. Pour coke/pepsi into the fork tip it fills up.. and let it sit in the fork a few days... you can refresh the coke/pepsi every few days.. At least try it letting it sit there for 3 full days before trying. .. The acid in the soda will break down the galvanized bonds over time.
After that try to use the handlebars as leverage twisting back and forth while pulling up..
Becareful while you do this since you can bend the fork or even damage the front wheel if you apply to much force.
I recommend that you let it setting for a full 7 days while maybe refreshing the soda about 2-3 times total. I had much better luck with a full 7 days.
You can also apply this method to removing a stuck seat post. However you'll need to remove the crankset and bottom bracket in this case.
I've pulled out 3 aluminum seatposts with no issues and 2 stems with no issues. Only the 3rd stem which was a $#*&, the bond broke and I can twist it back and forth. But it was so stuck I could not pull it out. I got it out half an inch. Eventually I decided to saw off the stem when the fork got bent, but luckly I have a spare fork I can use on that frame 1986 Schwinn passage with Columbus Tenax Tubing. Other frames and forks that I rescued were a 1988 Miyata Triplecross and a 1984 Schwinn Worldsport (4130 tubing).
Anyway If you do get it out, Make sure you grease it.. Do the same for your seatpost too.
Note: I have not tried PB blaster yet since I was looking for something less toxic such as soda But yeah having some kind of vise hold device will help, but becareful of bending the fork/frame or wheel.