How to remove a swing arm pivot pin bolt.

A look at your chassis
Post Reply
User avatar
Sandblaster
Posts: 6312
Joined: Thu Jun 07, 2012 3:50 pm
Location: Eugene, OR
Contact:

How to remove a swing arm pivot pin bolt.

Post by Sandblaster » Tue Sep 17, 2013 7:44 pm

As a dirt bike ages, many of the fasteners become corroded.
When the corrosion intrudes between the threads, things can get real hard to remove.
This is especially true when Swing arm pivot pin bolts are involved.
Really, how often do most people remove them?
Generally, not until they are ready to rebuild their bottom end and by then it can be too late :shock:
In fact, this problem is so common that most of the bike repair shops in our area will not work on your bike if it is over 10 years old :o
First, here's a small piece of advice, if you have a bike see if you can pull out the swing arm pivot pin.
If you can remove it, grease it up... You will thank me when you go to rebuild the bottom end.
So, here is the problem.
You go to remove the pivot pin.
The nut comes right off.... Yeah! Then you try to remove the pin and uh oh! it won't budge at all.... Now what?
Well, you can get a beater pin and a mallet and try to beat it out and sometimes it actually works...
Other times you destroy the pivot pin.
20130917_123852.jpg
20130917_123852.jpg (81.11 KiB) Viewed 4194 times
Using brute force has to be used with caution.
You can completely mushroom the end of your bolt and then it is useless and worse, it can make it harder to get the bolt out...
If brute force does not work, you can put the whole thing up in a press and try to press the bearings out.
However, it can be difficult to get the assembly up into a press and get it level and properly supported.
Even then I have completely smashed what was a perfectly good frame when the bolt refused to let go.

The method that often works the best is heat...
Getting both sides of the swing arm heated up can be tricky but more often then not, heat is what works the best...
If you use heat you will need to replace all the bearings and seals..... You would have probably had to any way but it's just a friendly heads up.
20130917_125327.jpg
20130917_125327.jpg (93.21 KiB) Viewed 4193 times
20130917_125332.jpg
20130917_125332.jpg (81.58 KiB) Viewed 4193 times
After getting both sides hot enough to cause the grease in the bearings to boil, get out the mallet and beater pin and go to town...
As a side note, missing the bolt with your hammer can result in serious injury so I always wear safety glasses and I use a pair of vice grips to hold the beater pin..
20130917_130443.jpg
20130917_130443.jpg (103.24 KiB) Viewed 4193 times
Of course in these pics I have the engine already out so these pics are to demonstrative how I do it... ;)

Still won't budge?
Man it's getting tough now...

What about drilling it out?
You can drill it out.
This is time consuming and can eat a few bits but it is possible.
The size of bit you need will depend on the size of the swing arm pivot pin so your on your own there...

In the past I have tried to cut them out with a Saws All./
The problem is, the inserts are hardened and I have ruined a lot of good blades without hardly making a scratch in the surface... :x
So I was down at our local Home Depot looking at the blades I have already tried and saw some blades from Diablo... an ominous name but I figured why not.
So I picked out one of those blades that has no teeth but rather has carbide embedded into the blade.
After about 20 seconds of cutting the blade was ruined and again I hardly made a scratch in it...
diablo.JPG
diablo.JPG (38.44 KiB) Viewed 4193 times
So I next tried a 18TPI blade for cutting Stainless Steel.
diablo SS.JPG
diablo SS.JPG (35.45 KiB) Viewed 4190 times
Without using any coolant (Water) I managed to cut almost all the way through one insert before the end of the blade was junk.
Later today I will try using water and see if I can cut through another and still have a usable blade when I'm done..
If bikes are for kids I'll never grow up.

User avatar
Sandblaster
Posts: 6312
Joined: Thu Jun 07, 2012 3:50 pm
Location: Eugene, OR
Contact:

Re: How to remove a swing arm pivot pin bolt.

Post by Sandblaster » Fri Jul 25, 2014 9:19 pm

Water works great.
Had my kid hold a small but steady stream of water on the blade as I cut the insert.
No problem, the blase ate right through it and is still working great...
If bikes are for kids I'll never grow up.

Post Reply

Return to “Chassis”

Who is online

Users browsing this forum: No registered users and 1 guest