Are Helicoils in mobile timing belt roller bolt holes standard? - 1000DS engine (and

[yellowfever]

(And other questions - my title got chopped a bit!)

I removed the mobile timing belt rollers as part of my work on investigating the suspected timing shaft oil seal leak on my 2006/S2R1000. I was surprised to find that all four bolt holes attaching the movable rollers have helicoils fitted.

Given they need to get loosened/tightened as part of routine servicing did Ducati fit helicoils from new as they’re stronger (I know they can be used as standard in aluminium for certain applications)? Does anyone know? Seen the same in their own Ducati engine(s)?

I’ve owned the bike from new and none of the highly regarded official dealer or independent pro mechanics I’ve used in the subsequent 18 years have ever mentioned stripping a thread, let alone all 4 (or charged me for sorting this!). And as these bolts have necessarily been loosened and tightened every 2 years for the regular belt service I always had done it would be weird if they all got stuck enough to strip, barring some impressive ham-fistedness using incorrect torque. So I guess this is normal / OE new from factory? But good to hear what others think…

Another discovery related to this was that the bolt hole for the adjuster screw for the vertical mobile belt roller is not completely blind - looks like it breaks through into the tunnel where a head stud goes (I think). See this photo.



Again is this normal? Or possibly a result of careless drilling when fitting a helicoil from new or later on? Anything to be worried about if not normal? (bolt hole was totally dry so it’s not a source of the oil leak. In any case gaskets should fully surround studs/stud tunnels).

Another weirdness is I’ve seen very small silver metal particles here and there under the area covered by the belt covers (see in photo).



I thought this might be from the oil seal as it has a metal tension ring, but it’s not nearly far enough gone to be that. It also doesn’t appear to be from any of the belt tension rollers which are all more or less fine I think. And anyway the metal particles are not magnetic (so aluminium I guess). So I wondered if it was possibly left over from helicoil drilling/tapping work if these helicoils are a post production fix done by one of the mechanics I’ve used over the years. Though another possibility is the inner timing roller rubbing on the cases (there do seem to be some very small wear marks here and there).

Any thoughts / wisdom on this long ramble appreciated!