SA Ball Bearing Conversion Kit

What I see is a PITA when the bearings need fresh grease. On the stock set up I remove the zerk, load a syringe with 140wt gear lube and inject through the threaded hole. With the modification to fix the spindle it works for as long as it gets more lube once a year.
 
I think the idea is there will be no further maintenance required. After all, modern bikes typically never need SA bearing lube replacement, same as the MKIII SA with Welch plugs and oil soaked fiber plugs within.

What bothers me on this bearing setup, the spindle is cut down at the ends to accommodate the bearings. Might this compromise load handling significantly?
 
I think the idea is there will be no further maintenance required. After all, modern bikes typically never need SA bearing lube replacement, same as the MKIII SA with Welch plugs and oil soaked fiber plugs within.

What bothers me on this bearing setup, the spindle is cut down at the ends to accommodate the bearings. Might this compromise load handling significantly?
I agree totally. If the material is the same as the stock spindle I'd estimate that the shear strength is about 80% less than stock - simply a function of the cross section. Now, the new spindle could be made from some exotic alloy. But who knows? And of course Norton may have hugely over engineered the original. But I doubt it. Btw, I love the idea, but no way would I risk fitting it.
 
I agree totally. If the material is the same as the stock spindle I'd estimate that the shear strength is about 80% less than stock - simply a function of the cross section. Now, the new spindle could be made from some exotic alloy. But who knows? And of course Norton may have hugely over engineered the original. But I doubt it. Btw, I love the idea, but no way would I risk fitting it.
Original is a hollow shaft to allow oil flow to bushings. I'd assume this kit uses a solid rod machine down at ends to fit within the bearings. That machined section would likely start right where the SA hinges at engine plates, right where all the shear loads will be maximum. Without knowing material and dimensions hard know loading limits.
 
What I see is a PITA when the bearings need fresh grease. On the stock set up I remove the zerk, load a syringe with 140wt gear lube and inject through the threaded hole. With the modification to fix the spindle it works for as long as it gets more lube once a year.
Dave,
I see that a lot of guys here use a syringe for various purposes.Where does one find such a tool and could you put a picture of yours here? I do the same process as you with a small oil pump tool with a small tip that works but would like to see what you are using.
Thanks,
Mike
 
Might this compromise load handling significantly?
When you compare this diameter to the long bolts used on some swing arm arrangements including the A65 and A75 then it should be up to the job.

What I found odd was how the bearings just dropped into the swingarm bush holes on both sides, so there is a clearance there which will show up as play at the end of the rear wheel.
 
I think the tapered roller bearing conversion that used to be available was probably a better bet
 
When you compare this diameter to the long bolts used on some swing arm arrangements including the A65 and A75 then it should be up to the job.

What I found odd was how the bearings just dropped into the swingarm bush holes on both sides, so there is a clearance there which will show up as play at the end of the rear wheel.
On the BSAs the pin/bolt is also supported by the outer frame plates, but not with the Norton conversion in the video. I modified my 750 a long time ago by cutting off the bush tubes & welding on new larger ones to take, if I remember correctly, a LJ7 2rs ball race each side, which means you can use the original pin.
I will post a picture when I get time, but it's a mod. that requires access to a horizontal borer, & to be honest it's really not necessary as the bushes work just fine.
 
On the BSAs the pin/bolt is also supported by the outer frame plates, but not with the Norton conversion in the video. I modified my 750 a long time ago by cutting off the bush tubes & welding on new larger ones to take, if I remember correctly, a LJ7 2rs ball race each side, which means you can use the original pin.
I will post a picture when I get time, but it's a mod. that requires access to a horizontal borer, & to be honest it's really not necessary as the bushes work just fine.
Yes I think all such a kit does for me is alleviate some fugly, sticky STP Oil Treatment seeping from the poor seals on my mkII. Otherwise my SA with Kegler clamp mod is performing fine..
 
Dave,
I see that a lot of guys here use a syringe for various purposes.Where does one find such a tool and could you put a picture of yours here? I do the same process as you with a small oil pump tool with a small tip that works but would like to see what you are using.
Thanks,
Mike
Bearing grease packing syringe a bit of Tygon fuel hose and a sports ball inflation needle.
SA Ball Bearing Conversion Kit
 
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