When I bought my 748SP many years ago it was suffering the same (just had a 600 mile service done by Daytona in Islington!!)....anyway, I got and impact driver and literally chisel a slot in the sump plug with it before I could turn it out. In such a situation I would advise you to go to a dealer or preferably some decent engineering workshop that could do it for you.
Had my 900SS for over 6 years now. The 1st time I tried to drain the oil I met the same problem as you. I got round it by removing the gauze filter on the right hand side of the engine low down, and then removing the oil filter. this drains most if not all of the old oil. Replace the 2 items and refill with fresh oil. Cheers, Bri.
Note: The sump plug's socket opening is tapered so it's easy to think the socket is fully in place when it's not. Then when you try to loosen it or torque it, it strips the soft plug. Happens alot.
use the methods already posted, and replace with a new OEM plug, or an aftermrket one.
Hi thanks to everybody that replied for your help think i will drain it out through the filter for now and get it done later just got to fit an evolution clutch slave cylinder then i am back on the road.