I cold start the old girl with choke and no throttle, as always and she starts first time, every time. She runs fine on idle but as soon as open the throttle a bit she misfires – I can just about coax her down the road on a very small throttle opening, just above idle, any more and she goes lumpy and misfires. After about five minutes as she warms up, she runs better and after ten minutes and for the rest of the day, she runs just fine.
First I thought it was the Newtronic ignition not getting sufficient voltage but with a new battery, freshly charged, the problem is still there. I now wonder if it’s the fuelling? The fuel tap is a free-flowing Pingel, so that shouldn’t be a problem. Does anyone have any ideas what I could try next please?
