tiger 650

My dad passed away and there was an old Triumph in his garage. I am having a devil of a time identifying it. I think I have it narrowed down to... Tiger T110 6T motor - 650 cc's Frame # is 6414N Engine # is 6T11585NA It has a K2FC Lucas Magneto 261 423680 I don't know a year for this or even...

Just started doing it over the weekend, I first thought maybe I had some bad gas or something but I filled up with fresh 90 ethanol free and doesn’t seem to matter. Happens in all gears right around 3500 rpm, almost feels like it’s out of gas or missing a cylinder. Could it be something to do...