12-05-2019, 08:23 PM
JonE - Yes, the Zeniths seemed to act the same. The original Zenith needed a good clean out but still couldn't get a consistent tick-over, and the newly refurbished Zenith was all over the place, but I put that down to the settings being out having never been fitted before.
Following advice on facebook I tried the oil test on the carb. inlet tract but nothing dramatic happened - changed the carb to inlet manifold gasket anyway. I'd like to think there was a hint of an improvement, but really just being overly optimistic - it still doesn't tick over without the choke. It seems an air leak could be part of the problem, but I can't detect it.
Chris - A lot of information and advice given - thanks. I'll reset the gaps to those you quote. It took nearly an hour to leave Woolaton last year on what was a red-hot day, nudging forward a yard at a time. My friend's RN boiled up in sympathy. The piston falls easily enough and I've used 3-in-1 oil in the damper. I'll follow yours and Hugh's advice and go back to the EB needle - I only changed it in the hope of weakening the mixture, but I'll adjust the main jet as Reckless suggests.
It looks like I can rule out the ignition side of things, apart from setting the timing more accurately, and focus on carb and mixture.
Fantastic response chaps - I hope I can do it all justice.
Following advice on facebook I tried the oil test on the carb. inlet tract but nothing dramatic happened - changed the carb to inlet manifold gasket anyway. I'd like to think there was a hint of an improvement, but really just being overly optimistic - it still doesn't tick over without the choke. It seems an air leak could be part of the problem, but I can't detect it.
Chris - A lot of information and advice given - thanks. I'll reset the gaps to those you quote. It took nearly an hour to leave Woolaton last year on what was a red-hot day, nudging forward a yard at a time. My friend's RN boiled up in sympathy. The piston falls easily enough and I've used 3-in-1 oil in the damper. I'll follow yours and Hugh's advice and go back to the EB needle - I only changed it in the hope of weakening the mixture, but I'll adjust the main jet as Reckless suggests.
It looks like I can rule out the ignition side of things, apart from setting the timing more accurately, and focus on carb and mixture.
Fantastic response chaps - I hope I can do it all justice.