Cheers Sanny.
I’ve taken a bike through the Lairig Ghru before, but going the other way from Rothiemurchus. It was the return leg of a big day out from Linn of Dee to Glenmore via Fords of A’an and back to Glen Luibeg. Going south the LG is pretty much unrideable for a long way (it’s a very on/off push lots/ride a bit until you get to the boulder field beyond the Pools of Dee then you get a stunning descent to Glen Luibeg (with a short climb just beyond Corrour Bothy).
Coming off Braeriach, you’d probably avoid most of the ball-ache section, but be prepared for some frustrating bits until you get to the nice section down to Picadilly.
My attitude to such rides is “there’s only really one way to find out…”
🙂