What you have to concern yoruself with is the distance between the limb forks. I never measured my 2008 limbs, but my 2005 ShadowCat has a spacing of about .800 between the limb forks. The newer limbs (2010) have a space of about .710. Therefore, the Cat2 cam must be narrower than the older Cat cam. This would lead me to believe that the newer Cat2 cam can indeed fit the older limbs. Of course you'd have to add spacers (shims, washers) to fill the gap, but this isn't much of an issue. Any good archery shop should have them in a repair kit.
As to whether the older limbs will hold up to the Cat2 cam? Only time will tell. A lot will depend on how hard you push the bow. How long the draw is set at and arrow weight, etc. It does seem Martin had an issue with the 2009 limbs.
The cam swap Simon was referring to was about putting Nitrous cams or other older cams in the 2010 limbs. From measuring I found the Nitrous will not fit. Maybe some of the other cams will, but that was not your question.
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