I have a problem at the moment, having fitted a new Amal pre-monobloc and a new BTH twin spark magneto to my Comet, having finally got the bike started yesterday after a winter restoration I am struggling like hell to get it started.
It is running a brand new 9:1 piston, with platinum NGK spark plugs and it has really good compression, but I struggle to get it to fire and start. When I eventually get it started, it runs and ticks-over nicely, but not knowing either the ignition or carburation, I have no datum to start from!.
Having looked at the hints and tips book that comes with the Amal, I see I can play with the choke slide at different throttle positions to try out for weakness etc, but the first problem I have is that should this be done while riding the bike ie under load, or can this be done at stand still? Also, while I had the bike ticking over earlier, setting the choke to fully open or fully closed made no difference to the engines speed, which confused me when every bike I have ever owned, touch that choke lever and all manor of things happen!.
Starting could also be a case of weak spark at the magneto, what with very little obvious firing when I pulled a plug yesterday until after a few prods of the kickstarter, but is this a case of the BTH needing a few prods to charge the system?
Having two major assemblies that could be the problem has got me stuck at the moment, has any body else had issues with first commisioning on either the Amal or the BTH? jets wrong from manufacture on the Amal? recommended ignition timing from BTH wrong? There was no obvious pinking on 99 octane, but I'm open to any suggestions at present.......
It is running a brand new 9:1 piston, with platinum NGK spark plugs and it has really good compression, but I struggle to get it to fire and start. When I eventually get it started, it runs and ticks-over nicely, but not knowing either the ignition or carburation, I have no datum to start from!.
Having looked at the hints and tips book that comes with the Amal, I see I can play with the choke slide at different throttle positions to try out for weakness etc, but the first problem I have is that should this be done while riding the bike ie under load, or can this be done at stand still? Also, while I had the bike ticking over earlier, setting the choke to fully open or fully closed made no difference to the engines speed, which confused me when every bike I have ever owned, touch that choke lever and all manor of things happen!.
Starting could also be a case of weak spark at the magneto, what with very little obvious firing when I pulled a plug yesterday until after a few prods of the kickstarter, but is this a case of the BTH needing a few prods to charge the system?
Having two major assemblies that could be the problem has got me stuck at the moment, has any body else had issues with first commisioning on either the Amal or the BTH? jets wrong from manufacture on the Amal? recommended ignition timing from BTH wrong? There was no obvious pinking on 99 octane, but I'm open to any suggestions at present.......