Belt Tensioners

The rollers shouldn't have any play in them what so ever.

Did you insure the C clip in the backside of the roller is in place and NOT damaged somehow? I know the bearing is press-fit, but ya never know!

Yeah, they're all in place and all undamaged.

Bosses are good, no wear, not loose either, eccentric adjusters on the mobile tensioners are nice and tight, these are basically new parts, there just seems to be lateral play in the bearing...

A little axial play (in/out) is ok. If they wobble or have radial play (up/down or left/right) - not good.

Just looking at these new bearings they've sent me, they're a c4, I'm no bearing expert but they obviously have more internal clearance than a regular bearing, do you think that would be enough to cause the play? I can't see the spec of the old ones as the writing has become eroded, they do seem to have a thicker inner race though.

actually forget that, looks like c4 is the right bearing spec.

I'm stumped.

Maybe that hex screw that holds the roller is simply not tight enough. If you loosen it up, the roller does come loose right away, even with the bearing solid on the boss. So I still think it's an assembly issue you need to resolve outside of the service manual. Figure out a solution to stop the play and make it happen. I had nothing but problems with rollers on Desmoquattro's which wouldn't line up with the cam's. Turns out, Ducati forgot to put spacers in the service manual or parts catalog. So all I had to do was put a spacer behind the roller and it lined right up! Moral of the story? Maybe ignore what Ducati says to do and just fix it how you know best.

^^^^ Oh hell yeah, Ducatis fault!!!! You've been "tooned"!!! :shrug:

.....just sayin.....