I have just got a 1962 arrow it starts ok but when i ride it it starts to cough and splutter and begins to bop and almost backfire.it will only reach about 30mph and eventualy cut out but will start again . I am a bit of a novice mechanic. I have checked there is a good spark at the plugs it has had a new mikuni carb fitted which i am unsure about ie what to check for in this area.
any help will be greatfuly received.
Thanks Mick