Swing Arm Mounting Question

Status
Not open for further replies.
The plot thickens.

Here is a spindle I found on eBay. It has the same bolts as mine. I don’t see bolts anywhere in the manuals to add the swing arm.

Why does this one have the same bolt?

So looking at this, the shaft is very thick and the outer circle on mine is the shaft?

Swing Arm Mounting Question

Swing Arm Mounting Question
 
Norcoastal said:
The plot thickens.

Here is a spindle I found on eBay. It has the same bolts as mine. I don’t see bolts anywhere in the manuals to add the swing arm.

Why does this one have the same bolt?

I’m even more confused.
Click to expand...

It's a standard every day 1/2-20 bolt used to extract the spindle. Not part of the assembly.
 
Norcoastal said:
How thick is the spindle?
Click to expand...

Diameter is 0.8745"

Norcoastal said:
Now I’m thinking I’m going to thread one of the big bolts into the threads and see if I can bang the shaft out.
Click to expand...

The spindle can also rust solid inside the tube which makes it extremely difficult to remove.

Norcoastal said:
Here is a spindle I found on eBay. It has the same bolts as mine. I don’t see bolts anywhere in the manuals to add the swing arm.

Why does this one have the same bolt?
Click to expand...

The spindle is threaded at both ends so it can be extracted using a bolt.
The bolt wouldn't normally be there.
 
So is the consensus to whack the hell out of it until the modified shaft comes free?

I can’t believe that the shaft tube is through the cradle, it’s probably just welded on the inside of the cradle and this entire shaft has to come out.
 
Norcoastal said:
Is the Keigler clamp absolutely necessary? I have to believe that there are hundreds of Norton’s out there without the clamps.

I want to do it the right way, but this isn’t going to be a road trip bike. I have my Ducati for that, this is going to be my hobby bike to just knock around town in.
Click to expand...

The Kegler clamps are inexpensive and remove all slack from the pin to tube fit.
Even with a new machine, there was slack in this fit to allow assembly and removal.
That slack multiplies at the back wheel.
The Kegler clamps have nothing to do with bushing to pin fit. Slack there will only add to overall rear wheel lateral movement.
Kegler clamps and Mk3 cotters are there to fix the swing arm pin solidly to the cradle so that the pin acts as though it is welded into the cradle, except it can be removed when needed.
As L.A.B. noted, if your final pin to tube fit is very good, then the rear wheel slop originating there will be minimal, although there will always be some without the Kegler clamps or MK3 cotters.
That's why I would fit the Kegler clamps to any pre MK3 bike.

Glen
 
It looks like someone has given up trying to remove the remains of a swing arm pin
If it's corroded solid then you will have to press it out
You will need to support it with a good fitting tube around the outside of the pin
And plenty of heat
You will need a good fitting parrelell pin punch or Arbor if you use a press , don't use anything tapered or you will make matters worse
Oversized pins are available if necessary
 
Kegler clamps seem to work well
Personally I prefer the MK3 conversion
I don't like the nuts welded on the swing arm pivot tube either
 
First you need to state (maybe missed) what the ID is of the threaded hole (or that bolt OD)
If it is well below the spindle size you might want to make sure those marks in one picture are not weld porosity before the big hammer comes out.
 
Norcoastal said:
The bolt looks to be 1/2”, the hole is 9/16?

Sorry, it’s not metric.

Swing Arm Mounting Question


Swing Arm Mounting Question
Click to expand...

The bolt looks bigger than 1/2".

The original threads wouldn't have gone that deep so it probably has been threaded 9/16".
 
L.A.B. said:
The bolt looks bigger than 1/2".

The original threads wouldn't have gone that deep so it probably has been threaded 9/16".
Click to expand...

If you are going to follow the beat it out advice (be it hot or cold) be careful.

Based on the bolt size that swing arm bore is modified.
If it has been welded and you follow the knock whatever that is out, hit it one way then the other.
If there is weld and it has been ground flush doing the above may fracture it at the join line.

Based on the tape measure that ring mark is around spindle OD size.
 
maylar said:
Is there a parts list for the bastard child MK2/MK2A with the Welch plugs and felts? My spindle and bushings are neither pre-MK2 or MK3. That page for 68-74 does not represent what's on my 74.
Click to expand...
My April 74 is one of those bastard children that does not follow the 2/2a parts list. I used the plugs, felts, short bushings, seals and spindle from the mk3 list and they fit perfectly. Note no cotters on mine either.

https://andover-norton.co.uk/en/shop-drawing/137/swinging-arm-suspension-units-chainguard
 
Time Warp said:
If you are going to follow the beat it out advice (be it hot or cold) be careful.

Based on the bolt size that swing arm bore is modified.
If it has been welded and you follow the knock whatever that is out, hit it one way then the other.
If there is weld and it has been ground flush doing the above may fracture it at the join line.

Based on the tape measure that ring mark is around spindle OD size.
Click to expand...
Absolutely I’d use heat. Good idea hitting either side.
 
L.A.B. said:
It looks nearer to 1.0" than 7/8" OD so might not be the original spindle after all.
Click to expand...

I'm fairly sure the big sledge hammer will not be to concerned and did say 'around (It was an edit add on)
I did look at the tape measure and it did look bigger than spindle OD but blocked it out (I used the same .8750" spiral flute reamer on my swing arm bushes as was used on the new cam shaft bushes) but how far would someone go as far as an insert ?
Only removal will find out and of course if it is over size, time for another cradle perhaps.
 
Norcoastal said:
Absolutely I’d use heat. Good idea hitting either side.
Click to expand...

As a time served Boilermaker/Welder I am already nervous. :D

My concern is as L.A.B said, that ring mark OD.
I did look at the tape but did not want to see a number bigger than spindle size (hence putting 'around )
The spindle pin seats in that area so a over size hole/bore is not good should that be the case.

Removal will soon see what you have but would someone go to the trouble of increasing that bore size, I hope not.
Hopefully it will break free and a new pin is a good fit.

Edit.
Just remember, you have to be sure there is something to break free and if there is how it is held in place.
If you do the push both ways be aware than any rag on the OD if not removed will scrape the OD if not removed.
If it protrudes a little, file that end if needed then push the other way.
 
Last edited:
Status
Not open for further replies.
Back
Top