Rebuilding brake calipers should be done every year, whether you ride track or street. Track bikes go through pads quicker, so they accumulate more brake dust. Street bikes get dirt, water, salt and all kinds of other shit in the brakes. Thoroughly cleaning will not only make your brakes work better, but your pads and discs will wear more evenly when the pistons aren't obstructed by a bunch of shit.
It's only slightly less messy than a fork rebuild, and brake fluid is bad stuff so this is probably the nastiest job you can do. Make sure you have plenty of rags and good nitrile gloves.
This was done on my SV650 with ZX-6R calipers, but the procedure is the same for 06-08 Daytonas and similar to 09+ (I'll get to that). Here we go!
Drain the brake fluid, preferably with a Mity-vac or similar to get as much out as possible.
Disconnect the banjo bolt, but make sure you have rags and/or a bottle handy to catch fluid because it's almost impossible to get it all out. No matter how much you shake and dance, etc etc...
The brake lines are free; I like to wrap them and hold them high so they don't drip on my garage anymore.
Loosen but don't remove the pad pin (Daytona only has 1 bolt in the middle). It's important to use a good, quality allen as these bolts seize easily and they can be torqued tightly considering how small they are.
Next, remove the big caliper bolts that hold it to the fork leg, again using a good allen. The caliper will now come back off the disc. Be careful not to tilt the calipers upside-down or you'll spill a bunch of fluid.
Pull out the pad pins and you'll have 2 pads per caliper (I have 4) and the anti-rattle clip (the silver thing in the middle). The clips aren't necessary & I've never used them on my track bikes, but you can do whatever you like.
Tilt each caliper into a bottle and drain as much of the fluid as you can.
For 06-08 2-piece calipers, it's a lot easier if you split them, so loosen the bolts that hold them together. My brakes have 3 bolts each. They're torqued down pretty good so I put them back on the fork leg to get more leverage. You could also use a vise with soft jaws if you're careful.
Now you'll have 2 halves:
The pistons need to come out now. My preferred method is blowing compressed air into the fluid passageway, but make sure you have a rag held tightly over the pistons so they don't go flying into your face. Make sure you're wearing goggles too because you'll probably get a little spray. Plug all the holes except one and blow away. You'll hear a pop when each piston comes out.
For 09+ monoblocs, you'll have to do this as one piece. I suggest putting a block of wood between 2 of the pistons and just working on 2 at a time.
You'll notice 2 rubber seals in each cylinder. Those need to come out, but be careful if you're going to reuse them. I pulled the old ones out with an X-acto since I'm replacing them anyway. A dental pick would work well too.
Now you can go about actually cleaning everything. If you're spoiled rotten, you have a sonic cleaner and you can just stick them in for a while. If you're like me, you need to just scrub away. I used a rag and some WD-40, but you can also use Simple Green, brake cleaner, or pretty much any other de-greaser. Once I got the top layer of grime off, I polished everything with a Dremel's brass brush attachment to make it all shiny again. Make sure you get in the seal grooves too because they can leave behind black stuff. Also clean the pistons so they slide easily. Before & after:
All ready for reassembly. Put a light coating of new brake fluid on the seals & pistons to lube them. I've also heard of people using red rubber grease for the seals. Put them back in just with your fingers.
Put the halves back together, then the pads, mount it back on the fork legs & reconnect the brake lines. The banjo bolt's washers should be replaced whenever you take the bolt out. Torque everything to spec, bleed the brake system and ride! (don't forget the wheel if you've removed it...)