Haven't used it for 2 years, stored in a leaky shed - emptied fuel, refilled with fresh, started on 2nd pull. Amazing! I was all ready to spend ages cleaning plug etc..
Have a Suzuki DT2 that does exactly the same, also a Briggs and Stratton powered lawnmower that provides no entertainmemt at all, every spring it starts a first pull.
What happened to the days of spending a day or so getting the lawnmower to run every spring?
Only problem is aged 2 stroke mixture which clogs up the carb. Solution is to unscrew the Phillips screw in the bottom of the float chamber, and dump the contents... then the o/b is great.
Took me a year to work it out, having been used to Seagulls which run on anything