- Unfortunately the original type Twin row self centering bronze caged ball bearing is now obsolete and no longer easily available (item no 0005), therefore extremely expensive. I can also supply this single row (non self centering) variety, also manufactured by RHP, as a cheaper alternative to fit to the TOP cambox bevel housing only, instead of the original twin row type.
The bearing still performs exactly the same function - but as this bearing has a fixed track (i.e. it is not of the 'self centering' variety) it means the vertical assembly is slightly less flexible, and therefore more fiddly to remove the cambox when the engine is in the frame. However, I have been told by other Norton friends and customers in the past that it is a comon/cheaper replacement and does still allow some movement.
NOTE: this bearing should not be fitted in the bottom bevel housing, where it is essential the original twin row self centering type is used. Please bear in mind that if using this bearing in the top housing, you should be very careful not to move the cambox off centre any more than necessary when stripping down, as it will force the bottom bearing off centre
Update April 2020: Almost as hard to source now as the original twin row bearing 0005 (although normally much cheaper when I can get them), I have managed to obtain a handful more of these as well. However - if you can afford it and we still have them in stock - I would still advise buying 0005 in preference to these, as they allow more movement when removing the cambox.