Bicycle Mechanics - Devised and made a tool to remove seized Modolo stem

The expander cone nut on my old Modolo quill stem was seized, and i couldn't remove it by hitting the head of the bolt with a hammer or mallet because it was deeply recessed and (horrors) it's made of aluminum. So, if I hammered on it with a drift pin, it would be ruined. So, I devised a tool made from a steel hex head bolt, by cutting off the head and cutting a slot in the end so that I could thread it into the expander nut with a long slotted screwdriver. I then hit the bolt with a steel drift pin and hammer, which dislodged the seized expander nut, allowing the stem to be removed. I did need to run a tap through the aluminum expander nut threads, which had gotten a bit boogered up during the hammering session. Just another one of those interesting problems one encounters working on vintage bikes.

I have mailed an application for a patent dated yesterday and my lawyer will
be in touch with you!

:roflmao2:

Good job there!

I think this may be a Park Stem Removal Tool. #SRT-312...

note the similarities.

236145

http://www.bikeforums.net/attachment.php?attachmentid=236124&d=1328396568

:roflmao2:

What was the diameter and threading of the bolt you used? I would have expected the OEM bolt to be metric and maybe M6x1.0.

i'm wondering whether he just turned the bolt into the plug just enough to center and secure it, meaning it wouldn't necessarily fit properly. then, used it essentially as a punch along with a real punch as an extension, to drive the plug out. that would explain the touching up he had to do with a tap afterwards. maybe he'll clarify later.

The bolt is actually M8x1.25, and it matched the threads in the expander. Problem is that the expander is aluminum and its threads are very soft, such that they deformed when I struck it with the hammer. I had to impact it very hard to dislodge it.

Brass/bronze drift punch is what is commonly used,
when you don't want to mark things..
Use a Metal, or wood, that is just a little softer.


or perhaps use a hex wrench in the socket of the bolt head. bang on it,
and you have the base of the hex head to take the effort.

The bolt is actually M8x1.25, and it matched the threads in the expander. Problem is that the expander is aluminum and its threads are very soft, such that they deformed when I struck it with the hammer. I had to impact it very hard to dislodge it.

understood.