Evening all.  

please bear with me. 

about at the end of my tether with my project bike.  but it’s fair to say electrics are not my strong point however this RT is getting me down.  Gathering parts I need is going well and had lots of help from people on here, but before I start building it up into a usable bike I want to get it to run.  Getting a spark is proving so difficult for me. Originally there was a weak spark most of the time.  Worth mentioning is that I have the early flywheel with the advance system built in if that’s relevant.

but now I have no spark other than a single spark randomly every now and again and I can’t replicate the circumstances to make it do it to order.  I have read everything I can and tried my best to rectify the issue but am banging my head against my workbench.  

I have replaced points, condenser, coil, plug lead and plug cap and plug.  I have taken the stator plate off and checked for obvious wiring defects.  I don’t know what I am doing with a meter really but have tried to follow instructions I have read on this site and elsewhere.  

I have checked wiring to the coil from the stator.  I have changed items with know working equipment from my RT2 (coil,plug lead cap etc). To no avail. 

could anyone suggest what this random rare spark may be a symptom of? I really am open to anything…. Maybe primary coil/winding?  Is it a rubbish condenser even though it’s new?  I don’t understand it enough really.  Mechanical stuff I can do or learn electrics is sorcery. 

Open to suggestions that I can try.

thank you in advance.   Ian. 

Very frustrating, Ian.

Before anyone asks, points and condenser are new genuine Yamaha, not knock off copies (well, at least that's what I sent to Ian!  ).

Yes. Frustrating. And I did fit the Yamaha parts supplied. Thanks as always Alan.

Spin it with a good drill anticlock of course & make it easy on yourself. Might make it spin easier with the blanked off plug hole open as well. In desperation I've tried the lowest output lighting coil wire fed onto the black at the plug coil but source coil needs isolating or wire unsoldered at condenser. So condenser has points & black heading up the loom. Then with lighting low voltage into black up top it feeds down to the points & condenser. Easy test when ya run out if options but still suspect the source coil when all else fails. Then again lighting coils can fail & cause confusion as ign source earth's Magic into the lighting coil. So on that theory you could earth the source coil direct to the mount post screw. Mine has no lighting coils so just direct earthed to the post. That's mag loom wire straight to the plug coil bypassing the main loom. Just have a way of stopping it if a drama unfolds stuck throttle etc.