A quick update, I adjusted the balancing screw and she now runs on all four. I've got my eye on a carb tune so I can set them up properly.

Thanks for everyone's help.

Good work and thanks for updating this post with your solution as it will help others who could be having the same problem in the future

I was maybe a little quick in celebrating as no.2 header is now not getting hot. I'm pretty certain it must just be the carbs need balancing. Anyone got one near Northamptonshire?

Thanks

i'm sort of having the same probs, however after managing to start the bike with choke on to keep it ticking over, once it's had about 5 mins, it'll run on all 4 cylinders, the one not having warmed up from start slowly getting warmer then being as hot as the other downpipes. I've harldy used it since about November so presume it's because of this. Once all warmed up, it doesn't miss a beat. Have you given it time to fully warm up? Still the same?

carb balancing is not a silver bullet. If the cylinder is not firing even when revved then there is something else wrong.

Balancing carbs only allows them to be closer in sync - it does not really make one or the other stop.


BTW - what screw were you tweaking?? You sure you were adjusting the balance screws and not the idle screw..which is another animal all together

If I give it some revs I do get some heat in the downpipe, it' just at idle I get no heat. I adjusted the far right balancing screw on the throttle linkage. This moved the problem from number three to number two.

If I let the bike run up to temp the downpipe does get warm but no where near as hot as the other three.

jasond wrote:i'm sort of having the same probs, however after managing to start the bike with choke on to keep it ticking over, once it's had about 5 mins, it'll run on all 4 cylinders, the one not having warmed up from start slowly getting warmer then being as hot as the other downpipes. I've harldy used it since about November so presume it's because of this. Once all warmed up, it doesn't miss a beat. Have you given it time to fully warm up? Still the same?

Snap.

Used my nc23 for the first time since bruntingthorpe on saturday. Was a pig to start and def wasnt on all 4 straight away but once I had given it time to warm up it was fine.