Tandem gear cable inner.
Gear changes on last weekend's Baldock 300 gradually decayed into something of a lottery, especially changes up (larger->smaller sprockets). Suspected a lazy cable - and that's what it turned out to be - the cable inner was very stiff inside the outer, at the dérailleur end of things.
New inner runs buttery smooth. Mmmm...
Lubed the chains too, which had become rather squeaky, within a couple of hundred km. I'm really not sure I'm a fan of dry-lube. It seems to need a lot more re-applications than wet-lube, even in warm, dry weather. That said, the chains are at least still silvery, and not thick black and sticky.