Author Topic: Problems removing cb750F swing arm  (Read 761 times)

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Offline 76four

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Problems removing cb750F swing arm
« on: June 20, 2014, 11:50:56 AM »
I am trying to remove my swing arm on my 77 cb750F.  I have removed the large nut fine but the large bolt that goes through the frame and swing arm won't pound out.  I broke it loose by using an impact wrench and some liquid wrench and now the bolt will spin slowly when I put the impact wrench to it or move the swing arm up and down.  I know it needs to be hammered out but the bolt won't move at all.  I even tried a sledge hammer as someone on the other end used the impact wrench.  I don't want to heat it because I don't want to repaint the frame.  Any other options?  I was thinking of trying a large C clamp or something to act as a press.  I've removed them fine on other bikes but this one has me scratching my head. 

Offline Don R

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Re: Problems removing cb750F swing arm
« Reply #1 on: June 20, 2014, 01:13:05 PM »
 I used the impact and pushing while it spins method. If you can get it to move add penetrating oil. Then in/put etc. Once you get it out a little put an open end wrench under the head and pry out while it turns.
 I like the seafoam penetrating oil. Only because I used that and got something apart when nothing else worked.
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Offline 76four

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Re: Problems removing cb750F swing arm
« Reply #2 on: June 20, 2014, 02:11:04 PM »
Thanks for the tips, I will give them a try and let you know what happens.

Offline Jerilee

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Re: Problems removing cb750F swing arm
« Reply #3 on: June 20, 2014, 02:40:18 PM »
You can also try greasing the zerk fitting, or taking it off to get some penetrating oil in the middle of the arm there.
I hope you have better luck than I did, it took so much force with mine that I buggered the threads getting it out. These 77-78F swingarm bolts are hard to find, they are longer than all the K bolts. So try not to dammage your threads too. Good luck!
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Offline Grabcon

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Re: Problems removing cb750F swing arm
« Reply #4 on: June 20, 2014, 02:42:00 PM »
It sounds like the pivot bolt is seized in the bushings and the bushings are spinning in the swing arm. I would try to pump some grease thru the grease zerk and see if that help. It may take a fair amount since it sounds like it has never been greased. As mentioned a little heat may help to liquefy the grease a bit and get the grease between the pivot bolt and the bushing.
CB750   1974 - Gone
CB750F 1976 - Gone :(
CB550   1978 - Gone & now back
CB900F 1981 - Gone
ST1100 1991 - Gone
ST1100 2000 - Gone
VFR800 2008 - Gone
ST1300 2008 - Gone
BMW F700GS - Wife's
VFR1200X 2016 - Mine

Offline 76four

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Re: Problems removing cb750F swing arm
« Reply #5 on: June 23, 2014, 06:27:32 PM »
Update: I just kept squirting the liquid wrench in there for another 3 days and then hammered it out okay after that.  The bolt that goes all the way through had a lot of rust on it and no grease.  There was no grease in the swing arm at all. Once the bolt was out the swing arm was pretty tight in between the frame still so I had to knock it out with a rubber mallet.  Does this mean my bushings are still good since there was no play?  What are some signs that I will need new bushings or seals?  The rust on the long bolt was mainly where it goes through the bushings and frame. Here are a few pictures if it helps.