Thanks, you're right, that's really shortsighted design. Obviously going to be plastered in chain lube and get blocked.
BTW this photo is of a 1260 drain hole but all the others are the same. The wire is about 40cm long and no way I can see of getting at the underside with a drill / countersink bit - at least not with what I have in the workshop. If the bike was upside down it maybe easier! The drain hole is visible with the shock removed but only the top side of it, getting at it from underneath is a pig, seems to part of the casting or drilled out after the casting.
Just read the thread. Glad I'm not the only one that has this problem . I've tried poking around from the top and managed to dislodge lots of tiny grit but not sure if that has solved the problem. I usually just soak it up by prodding a microfibre cloth in a few times. Will have a more detailed look next time I wash it and maybe try some of the tar remover suggestion.
I use a large syringe (obtained from my dog's vet) with a bit of silicone tubing, to get under the shock mount, to suck out the water after cleaning. I also have an unfolded and bent at a right angle XL paper clip that I clear the hole with from underneath each time I remove the rear wheel.
Yes as above it can be cleared from underneath easier with the wheel Off but can be done insitu Last time I had my shock out I drilled the drain out to 6mm and it’s not blocked since If the original posters swing arm is full as well then the lower drain under the rear hub is blocked as well, at least this one is easy to access
They all do it guvnah ... broddle the hole clear from underneath the swingarm. Takes literally seconds.