We pulled the plug and it was a bit dirty. When I bought the bike the plugs had been taken out, so it was sitting with the plugs out since 2011, maybe its dirty? The carbs are coming back off next week so a clogged jet will be found if that's the case. I'll check the HT lead too.
I'd like to know what fuel filter is recommended, now would be a good time to install one since the tank is off. Any helpful advice for this filter install? I haven't searched the forum yet, I'll do that too.