I’ve just put the top-end back on after the repair and replate (by Aptec www.poetonaptec.co.uk) and I’m still getting poor ignition on the front cylinder. If I disconnect the rear plug lead it seems to fire ok and it starts to warm up ok. I’ve put on new coils and swapped plugs over as well. The carbs were removed & cleaned. Compression seems much better than before, but that’s not a surprise considering the previous state of the front cylinder!
I haven’t given the bike a good run yet, because I need to sort out the coolant leak from the pipe connecting to the lower rear cylinder first.
I know the slow run jets could be the problem, but because it seems to run ok on one cylinder I thought it might not be the case

Any suggestions?