Been doing a bit of digging. You find out something new everyday!

It would appear that from mid 2012 the fork internals changed from Paioli to Kayaba/KYB (both Paioli and KYB parts are listed for the 2012 model year). The KYB ones have the raised hex head adjusters, rather than the recessed type on early forks. The part numbers for the springs and spacers are different between the two types.

I had no idea that the internals had changed, although I did know the preload adjusters had, but thought that was it. The measurements I gave earlier were from my 2008 model with Paioli internals.

However, if you've been supplied with Ohlins 08716-60 springs, they are exactly the same as mine, so the spacer dimension required is going to be somewhere around the 40mm mark (depending on how deep the new type preload adjuster is?) What's the Ohlins part number on the box?

Interestingly Ohlins only list fork springs for up to 2010/2011 bikes. Technically, they don't exist for 2012 KYB equipped bikes?

Try the different years in the search: https://www.ohlins.eu/en/motorcycle/search/?Brand=35&Model=XT+660+Z+T%E9n%E9r%E9&Year=2008

Best contact OTR, maybe Ohlins too. Could be some useful information to be gained here worth sharing with others with post 2011 bikes...

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