The Snidal Manual has wiring diagrams, find the ones closest to your bike and go from there.
You might try disconnecting the kill switch wires if you have the headlight out, I believe it grounds around the points, might possibly have a high resistance leak to ground adversely affecting the coil circuit operation.
Sparking when a test gap is introduced may indicate a weak ignition coil. The additional air gap allows the charge to build up a bit more before it jumps the gap. What are your coil primary & secondary ohm readings?
Personally I prefer points on the Bullet. The whole idea of owning a Bullet is to experience motorcycling's Neolithic past. Points simplify the troubleshooting process. Electro-gizzys are great, but the stock Bullet points ignition is adequate for the application and is simpler to troubleshoot: Points clean & dry?...Check. Voltage to points?...Check. Spark at plug when points break open?...If Yes - you're done. If No, bad capacitor, coil on a holiday, spark plug mystery failure or plug wire has fallen off...as I found out one day after a 1/4 mile push.
The intake rubber from the carb to the head spigot if infamous for cracking & diluting the charge, which can affect starting. Cut a 1 3/8" piece of 1 1/4" fiber reinforced radiator hose and get two appropriate sized stainless steel hose clamps and put paid to that failure mechanism permanently.
Get a Snidal manual and dig in to the basics. If it's relatively stock, has enough compression to push your thumb off of the spark plug hole when kicking over with the throttle open, has a clean carb full of fuel & spark at the right time it HAS to run. Just methodically make those things happen.
The Pete Snidal Motorcycle Manuals
http://www.enfield.20m.com/bullet1.htmHitchcocks can have this stuff to you in 4-6 days most times.
https://accessories.hitchcocksmotorcycles.com/2155?qty=1&continue_url=https%3A%2F%2Fwww.hitchcocksmotorcycles.com%2Fpartsbook-pages%2F1825PART No. 144146 ; £77.00 ; C/B PLATE, CAM AND AUTOADVANCE UNIT ASSY, 500, 535 AND 350cc AFTER 06/98
https://accessories.hitchcocksmotorcycles.com/accessory-shop/Spark-Plug-Cap/1686PART No. 142586 ; £3.30
SPARK PLUG CAP NGK (RED)
https://accessories.hitchcocksmotorcycles.com/accessory-shop/Coil-PVL/18674PART No. 92025 ; £43.50
COIL WITH BRACKET, 12v (PVL)
PART No. 90154 ; £10.80 ; STARTER MOTOR BLANK
If you have removed the starter motor and do not want to go to the expense and effort of changing the chaincase, then this is a simple to fit alloy plug that seals the hole that is left behind.
- OR -
https://accessories.hitchcocksmotorcycles.com/accessory-shop/ignition/34789 PART No. 90158 ; £539.00
ELECTRIC STARTER UPGRADE KIT (ALTON)
The Electric Starter Upgrade kit (Alton), exclusive to Hitchcocks Motorcycles, has been developed to alleviate the problem of sprag clutch failure on electric start Bullet and Electra X engines. This kit, which has taken four years in development and testing, comprises a replacement idler gear; a replacement driving gear; an improved starter solenoid; and a set of improved electrical leads to provide maximum current transfer.
Many owners of pre-EFI electric start Bullet and Electra X engines have experienced repeated and expensive failures of the one-way sprag clutch bearing and gears. While the sprag clutch bearing itself is a satisfactory item, they are easily damaged when forced to run ‘backwards’ by an engine ‘kick-back’. Engine ‘kick-back’ may be caused by any number of factors and is difficult to eliminate entirely. The bearing and gears needed for these repairs are amongst the most expensive single items in these engines and with labour costs repair bills run into hundreds of pounds. Even after repair the sprag clutch is liable to fail again (and again!) at any time.
The Alton upgrade kit includes an idler gear incorporating a cush drive arrangement with 6 shock absorbing buffers. The buffers cushion the effects of an engine ‘kick-back’ to safeguard against sprag clutch failure.
This upgrade kit will not only help protect against sprag clutch failure from engine ‘kick-back’ but the upgrade kit will also help with starting in general as a result of a number of other improvements incorporated in the kit components.
Please note: the Electric Starter Upgrade kit does not include the sprag clutch assembly - which is still required.