Had can chain tensioner replaced by dealer, owing to a slight rattle when cold (common on Kwaks) ZX6R
Picked bike up, rode down road and bike jerked upon acceleration. Went straight to add fuel (light had just come on) Bike continued to do it, happens regardless of gear, between 6-7k revs?
Brought bike straight back to dealer, who statd they will stip it back down and check what the have done. They stated that something, or water in the fuel may have caused it? But, how can this be if it happens exactly at 6-7k?