Steering Tube Obstruction

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Hello fellas,
Need some fork anatomy explanation. I'm attempting to install an extender in a fork that has something in the way that can't be easily reamed several inches in.
Model mid 70's Sears Free Spirit MX 21.1mm I.D. fork.
Sears Free Spirit MX fork.jpg


Bottom view
Sears Free Spirit MX fork under.jpg


The obstruction. What's its purpose and how can it be removed without destroying the fork?
It's about 3'' from the bottom.
steerer.jpg
 
The fender mount is less of an issue. I want to know specially what the plug thing is and how it can be removed. Appears to be made of two parts. I can't see clear enough. Is it something pressed in? Does the bottom of steerer have an extra thick wall? I've reamed forks with a taper near the crown to open it up further but I'm unsure what I'm dealing with here.
 
The plug looks similar a split roll pin...from the bottom you can see two swedges to stop it from working it's way out.

It looks like it was meant to reinforce the lower end of the fork tube.

You could try dremeling or grinding off the swedges and pressing it through...or....get a big drill (slightly less than ID of tube) and a drill press and slowly try and drill it out.
 
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Thanks for your input Rusty. Hopefully soon, a member who's dealt with this can provide a best answer.


"Slowly try" is not my credo. I'm being patient this time before going about something entirely unnecessary.
The DeWalt is on standby...
 
An inside bearing puller would be my tool of choice to do this. There are both slide hammer and screw types. Probably not much help unless you have access to one.
 
An inside bearing puller would be my tool of choice to do this. There are both slide hammer and screw types. Probably not much help unless you have access to one.
Thanks tater. Where would you apply the holding force, and what direction would you pull from?


Cut the extender down to fit the existing space. It should have enough room in the existing space in the steerer tube for minimum insertion.
I'm extending a steering tube by an inch without welding. The steering tube gets cut down. The extender is bologna as much as possible and the top is threaded for the race and lock nuts. I need more depth of the side that inserts into the steering tube. The obstruction is at the masking tape line from the top.
extend.JPG


Would like to know how it separates from the steerer though. I see what appears to be separate component. I hit it with a punch to get feel. Be ideal if it could be completely removed by some means rather than partially by drilling down from the top for as much usable length of the extender.
fork.jpg
 
I'd remove the fender mount, pull it from the bottom and weld the mount back in if you are going to use it. My smallest screw type puller would probably fit in between the fork legs. It could be clamped in a vise to use a slide hammer puller.
 
I'd remove the fender mount, pull it from the bottom and weld the mount back in if you are going to use it. My smallest screw type puller would probably fit in between the fork legs. It could be clamped in a vise to use a slide hammer puller.
Thanks again, I have a slide hammer but unsure how much pressure is required. I suspect a lot.

Soak it down or heat it and slide hammer that sucker out the bottom side
I'll start by soaking. I don't want to damage the chrome with high heat. I can't tell if it's been brazed welded in. I don't see any evidence of that. Limited vision. I can only use a camera to see what going on. I still don't understand how it's installed and want to know fully.
 
Thanks again, I have a slide hammer but unsure how much pressure is required. I suspect a lot.


I'll start by soaking. I don't want to damage the chrome with high heat. I can't tell if it's been brazed welded in. I don't see any evidence of that. Limited vision. I can only use a camera to see what going on. I still don't understand how it's installed and want to know fully.
Definitely looks to be a split roll so it's probably just pressed in.

steerer~2.jpg




Could be brazed but even then shouldn't be too hard
 
I will step in here I have drilled out a couple for motor bike leaf spring purposes, and don't think you will be able to press it out, as I believe they are brazed in. Doing from the bottom, fork legs are in the way,. Believe me when I say best bet is the find a machine shop to ream it or drill it. ....Curt
 
NO WAY it will slam out cold. The fork legs interfere with the slide hammer's handle for one. There's not enough throw either way.

Cleared the end very well before using penetrating fluid. Used a heavy steel rod from the top striking it with everything I had! Just laughed at me. I suspected so, worth trying tho.
fork2.jpg


Should be drilled. For my purpose the fork will be plenty strong without the reinforcement, especially being the thicker wall 21.1mm ID.
Been meaning to order a new drill bit for these jobs anyway.
 
I'm with Karate Chicken--just shorten the extender so it doesn't reach as far. You'll need a shorter bolt for the wedge, but it's a way easier fix in the long run.
As I stated earlier. I need a bit more insertion in the steerer for proper fitment to make it function safely. I'll eventually have to bologna cut both extension and stem.
 
Have you thought about shortening the quill section of the extender? Just make a new angled slice at the end of the extender that will work with a shorter quill stem bolt and wedge.
 
Have you thought about shortening the quill section of the extender? Just make a new angled slice at the end of the extender that will work with a shorter quill stem bolt and wedge.
That's the problem and what I'm getting at. The quill extension will become too short including the wedge. If I had another inch or so before the shoulder/obstruction it would be doable. In some cases I've filed down the outside radius of the wedge a couple of mm to set the stem a bit lower without tampering the with inside of the steering tube. That however reduces surface area and I need as mush as possible for this gig.
 

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