I had a problem recently with bleeding my front calipers, I tried everything like removing the calipers, moving them around, knocking them with a mallet to release any bubbles, zip-tying down the lever overnight, opening and bleeding the banjo bolt by the master etc. etc. I still had a brake lever that I could pull all the way in easily.
The only way I solved it was fitting speed bleeders, I ordered them on next day delivery. Fitted them in about 5 minutes, bled the system again and it was much better. The lever still pulls in further than before but I've got adjustable levers and moved them out, braking is fine and hard now. I think the problem was that the clear tube I had over the bleed nipple wasn't tight enough and let air back in every time I tried bleeding, with the speed bleeders that can't happen.
2006 SV1000SZ, Pipe Werx Titanium high level cans, GSXR K9 Front End, GSXR 1000 2014 Wheels, R6 Calipers, Brembo RCS Master, ZX10R Shock, PC III, K&N, de-snorkelled, tank raised, TPS & TRE, Watsen indicators, Carbon hugger, Suzuki Gel seat & cowl, Fabbri DB Screen..etc..