swingarm bearing conversion?

Status
Not open for further replies.
Joined
Feb 20, 2008
Messages
114
I am getting frustrated trying to keep oil in my swingarm,(yes it has been completely rebuilt).
My question is does anybody out there have the bearing conversion specs, and what is involved?

Planning on a long distance ride next year and really dont want to be filling that up every couple of hundred miles(less oil to carry)

Any info much appreco.
 
Joined
Apr 7, 2004
Messages
1,691
Remove the high hat bushings and cut them down in a lathe to 5MM long leaving the high hat. Be careful on the R&R therefore. Use a pair of Timken B-1416 mother company Torington to replace the portion of the bushing you removed. Pre-pack with a high quality grease.
 

L.A.B.

Moderator
VIP MEMBER
Joined
Nov 20, 2004
Messages
18,489
Country flag
mcns said:
I am getting frustrated trying to keep oil in my swingarm,

You don't really need to "keep oil" in the pivot, as the bushes are made of Oilite* (sintered bronze) which is porous and so absorbs a certain amount of oil, and once "primed" are more-or-less self lubricating, only needing a few drops of oil adding occasionally.


*Oilite "The original self-lubricating bearing": http://www.oilitebearings.com/home


Any oil that leaks out is just excess oil.
 
Joined
Apr 15, 2004
Messages
1,616
Country flag
L.A.B. said:
Any oil that leaks out is just excess oil.

It's not a design flaw, it's a feature! The excess oil automatically drains away, and all the owner has to do is wipe it off with a soft cloth. :D

I did the needle bearing conversion on my 750, but the new swingarm spindles do not appear to be hardened so I would expect them to wear quickly when used with the bearings. Because of that I retained the stock bushes in my 850 (it needed a new spindle). The excess oil all leaked out in a week and as Les said, what remained should be good for an entire riding season.

Debby
 
Joined
May 19, 2006
Messages
1,612
Country flag
debby said:
It's not a design flaw, it's a feature! The excess oil automatically drains away, and all the owner has to do is wipe it off with a soft cloth. :D Debby

I love that phrase Debby, it can be applied to so many aspects of Norton ownership :D
 
Joined
Jul 15, 2007
Messages
247
Country flag
They usually leak because it's hard to find the recommended SAE 140 lube. I have been using a 50\50 mix of 90W gear oil and STP which thickens up quite nicely and seems to stay in much better.
 
Joined
Jul 18, 2004
Messages
327
As Halloween just passed I thought I'd put on a cheerleading costume :shock: and say that this was possibly the PERFECT forum thread.

All the elements were there.
Good question, perfect response (including part numbers..!), feedback on the pro's and cons.

What a great forum -thanks and keep it up!

I'll need you when I tear into the dusty 850 hiding in the back of the garage.
 
Joined
Apr 2, 2008
Messages
492
Country flag
I know it's not perfect and certainly not something to do after a rebuild but aren't lots of these filled with grease and surviving pretty well in that environment?
 
Joined
Sep 20, 2005
Messages
66
The needle bearing is one of those "looks like a good idea" that doesn't work.
The original bushing is not only (more or less) self-lubricating) but has far higher load capacity than a needle, and doesn't require a specific minimum surface hardness (or finish) to run on.
A needle bearing is designed to run only on a hardened and smooth surface, and will brinnel even this eventually.
There is also no gain to be had in any event - the swing-arm pivot does not rotate in the bearings but only oscillates a few degrees, so the difference in friction is too small to matter.
Since the contact sweep area is very small (30°?, or 1/12th of a circle), the pivot will develop small depressions only where the needles pass over them. Each needle only traverses a small fraction of an inch of pivot surface (rather than average the wear out over the entire circumference, as would be the case if there were rotation).
The needle bearings have no thrust (end play) control, so the lateral load must still be controlled by bushings.
The Harley-Davidson swing-arms (since 1952) use Timken bearings, which control both radial and end thrust but are larger, heavier and more expensive.
 
Status
Not open for further replies.
Top