I e-mailed KAM and asked a few probing questions.
Firstly they told me that (at present) the internal cage/ball bearings of their CVs are interchangeable with the AEU2522.
As for the stub-less bell they told me that they are currently a "similar" material to the AEUs so not much difference if this is true. He then goes on to say
"but we are now starting to produce our CV's (inner and outer parts) with a metal conditioning process to further increase strength and durability, and finishing them with a Formula 1 type external polishing process."
I also asked if the bells were available seperately to which he replied that they were not at the moment, but they have never been asked this before and will consider this once pricing has been worked out.
The rest I will just quote from the e-mail response although obviously I can't be blamed if I accidently copy and paste it wrong!
[disclaimer off!]
"The KAM "fusible" stub shaft is, as you mentioned designed to be a "manageable" weak link (not just a weak link !), and many triallers/racers prefer to change a snapped stub in a few minutes instead of the hassle of repairing the CV/Half shaft/diff etc... but of course, not breaking at all would be better......but with the space constraints of a Rover axle, beefing things up can get a bit "tight" ......... As I'm sure you appreciate, as vehicles become more and more powerful, with more torque due to bigger tyres etc a weak link will inevitably be found somewhere down the drive train, so why not manage it ? ..... As mentioned above, we are now having some CV housings specially processed which should give approx 300-400 increase in fatigue and 30% increase in strength, so this should help somewhat. (I would still prefer to have a manageable weak link for peace of mind...as it's only fitted to protect the more expensive parts and reduce down time!)
As regards to when CV's or Stub shafts snap..... It, as I'm sure you aware, this depends as much on driver ability almost as much as the engineering or materials themselves, especially on Rovers... as the halfshafts/CV's are so limited by size compared to say a DANA axle etc.
Booting a 35" tyred race prepped vehicle on full lock, and up against rocks etc is always going to cause problems....!
Our fusible stubs can also be tailored to suit the type of vehicle being fitted to for example :- less radius for STD L-R and greater radius for bigger tyres, bigger engines... etc Of course we can still supply stubs without the fusible link, which are 24 splined type.
To develop our fusible stub "shear" points, we worked in liaison with Maddison 4 X 4 who tested the stubs in their GMC 5 1/2 litre, Rain Forest Challenge Rovers..... Since then we have sold over 100 CV conversion sets and only 2 CV Bells have been broken, so we can claim a 98% success rate (or only 2% Failure if you look at it that way!) A "normal" Rover will not shear the fusible stub unless it is in extreme problems...but it will break before the CV does."
The chap seemed very helpful - Richard Tracy at KAM - so hopefully they will not mind if I pass on this info.
I looked into doing this sort of thing but decided there were other options that'd be cheaper.
