Is there a swing arm spindle replacement/upgrade kit that is leak proof for my 1973 850 ?

Thanks. There is no machining required but I wonder if someone has installed it on an assembled bike
 
DennisMo said:
Thanks. There is no machining required but I wonder if someone has installed it on an assembled bike
Click to expand...
Yes, kit can be installed with just the SA removed as per the kit instructions. My concern was if the machined down spindle ends for bearing race fitment would still be strong enough.
 
British Cycle has been promoting this for a while now. As I recall it struck me as a solution in search of a problem.
I admit I seldom get around to lubricating the bushes. But my sense is the bushes seldom wear out. Usually the play comes from out of adjustment rear isos, or a wallowed out swing arm. Am I missing something here?
 
Maybe I am worrying too much?
Here is an idea. Thicken the 140W oil with a little STP (but not too thick), then less likely to dribble out?
Dennis
 
It would be really helpful to understand where the oil is leaking from; knackered O-rings or blown locking bolt on the cradle?

I've personally never experienced a leak here, and all the bikes ran an unmodified swingarm & cradle.
 
I just did mine.. I just did the stock pin upgrade. After I got it all back together I found my transmission cradle is worn. good ting I have a few of them. :)
 
The oil is intended to recharge the porous sintered bronze bushes so I don't know if it would be a good idea to thicken it. When that has been done the excess oil can drain away. One thing an owner can do if they want to try to keep more oil in the assembly is replace the dust covers and O-rings with the later sealed system pivot seals.
andover-norton.co.uk

Andover Norton - SWING-ARM PIVOT SEAL - 06.5227

SWING-ARM PIVOT SEAL
andover-norton.co.uk
 
On my bike it is the two inside seals that are leaking, but it seems to take the motion of riding to make them leak.
I figure that if I open all that up, I will only do it once and never again!
Dennis
 
Thickening the oil makes no difference to the drooling....I run straight STP oil treatment additive from advice from the fourm a few years back....to help slow down the drool. I recall the Hobot stating he uses "Corn Harvestor Grease"...which stays solid when still but liquifies when moving. Others have tried graphite bushings with reports of great success. But, it is just part of the quirkiness of hte bike IMHO...let her drool away.
 
The stock bushes are fine. If the cradle is in good condition, & as LAB suggests, fitted with the later type of seals, then all should be well. Years ago on my '68 750 I cut ff the swing arm bearing housings & welded on a pair of larger housings. I set the S/A up on the horizontal borer & bored to fit a pair of bearings each side. The bearings had the same i/d as the original spindle.
This was done many miles ago & I haven't touched it since, but I think it is totally unnecessary & I only did it because I could. Also, rolling element bearings are designed to revolve, which they don't do when used in this application.
 
DennisMo said:
On my bike it is the two inside seals that are leaking, but it seems to take the motion of riding to make them leak.
I figure that if I open all that up, I will only do it once and never again!
Dennis
Click to expand...
Dennis,
If you have it apart from,do as LAB says and put in the later seals and reassemble with 140W oil and be done with it. I oil mine about every 6 months and it might drip for a week but I figure the bushings are saturated and have never had to fit an oversized spindle but mine was in good shape from when I bought it 35 years ago.StarvingPhoto is in the process of fitting the kit from BCS and I am anxious to see how it works out.
Mike
 
Gear lube and motor oil weights are different. So, one of your better options is to get 60 or 70 straight weight Harley oil or similar, I would prefer just oil fashioned oil without a lot of additives. It is really about the attention to detail and the skill of assembly that prevents leaks.

bobistheoilguy.com

Viscosity Charts - Bob is the Oil Guy

iso viscosity classification system Many petroleum products are graded according to the ISO Viscosity Classification System, approved by the international standards organization (ISO). Each ISO viscosity grade number corresponds to the mid-point of a viscosity range expressed in centistokes(cSt)...
bobistheoilguy.com
 
Graphite impregnated.

Is there a swing arm spindle replacement/upgrade kit that is leak proof for my 1973 850 ?Is there a swing arm spindle replacement/upgrade kit that is leak proof for my 1973 850 ?Is there a swing arm spindle replacement/upgrade kit that is leak proof for my 1973 850 ?Is there a swing arm spindle replacement/upgrade kit that is leak proof for my 1973 850 ?Is there a swing arm spindle replacement/upgrade kit that is leak proof for my 1973 850 ?
 
Thanks lineslinger, I'm glad someone appreciated my efforts. The norton design is really bad. A leak waiting to happen. The sintered bronze bushings are also soft and wear out causing a wobbly rear end. If people want the no leak design, I can provide but I have to order 50 plus to make any economic sense.
 
More in this thread:
S

Post in thread 'Lubing swingarm. What could possibly go wrong?'

Guido said:
Someone had mentioned they saw a post on this mod. It may have been mine. I posted it years ago.
First off I did the Keigler clamp mod to the swingarms cradle and as i was doing that
I came up with this mod to make it easier to oil.
I took the center bolt out which locates the swingarms shaft.
I found a socket head bolt, drilled the center out and JB welded in a barbed brass nipple.
I then put clear plastic tubing to reach up to the top of the oil tank.
I then took out the nipple on the end cap for venting and with a hypodermic needle, without the needle, I filled the tube with 170w...
Click to expand...
 
DennisMo said:
It is the last leak I need to deal with!
Thanks
Dennis
Click to expand...
Replace the existing sintered bearings with bearings machined from lube impregnated polymer bush known as Ertalyte TX manufactured by Dotmar. There is a Norton owner in Australia that makes and sells these on xbay Australia.
 
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