Not absolutely sure what oil is in the forks out the box, but 5W rings a bell? It is pretty thin anyway!

Be wary that different oil manufacturers grade their oil differently – some use #W, some use SAE# and Ohlins have their own unique grading system; so when experimenting always use oil from of the same brand. I tend to stick with ones that use the SAE grading, because that is actually an international standard and consistent.

Spacers will only help with preload, so if you can’t get the rider sag you require (usually 25-33% of available travel) with the preload adjusters on the fork tops, then adding spacers will help. They will not change the spring rate compression, or rebound damping. Adding spacers will reduce the effective travel of the forks as they will get coil-bound much earlier in the stroke. If you can’t get the sag within spec then realistically new springs, set for your weight and riding conditions, are the only way forward (and they aren’t actually that expensive).

FYI - I am riding the Tenere with Ohlins 60N springs and Fuchs SAE10 oil at the moment – and it feels good.

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