Just bought this bike earlier this week and everything seems to be alright except for this "hiccup" that it seems to have. the bike sat for awhile (~6 months) after being rebuilt due to previous owner breaking his back. Ive taken it on a 1 hour ride and seems to ride well but does have backfire/popping issues on hard decel. it does have an exhaust leak where the slip on connects to the primary's that I have not fixed yet.
Specs:
2000 MZ Baghira 660
slip on pipe from 2010 yzf450
recently rebuilt by yamaha (1200 miles)
stock carbs
Im pretty mechanically inclined but havent ever owned a MZ or anything with the yamaha 660 motor for that matter. any help is appriciated I have attached a video for your viewing and diagnosing pleasure.
http://vid358.photobucket.com/albums/oo28/bamfpirate/Bike/90B65384-153A-4F85-AEFA-23711D098278_zpsdhohbpux.mp4