No spark means stop tearing the carb. Magneto and CDI details vary by platform — this is an elimination list grounded in the Puch, Tomos, and Honda guides plus the maintenance hub. Classic pedal mopeds only (not scooters).
Quick elimination (do these first)
- Known-good plug, gapped per manual. Common examples on this site: Puch often NGK B6HS; Tomos BR6HS (CDI) or B6HS (points); the maintenance hub also lists B7HS on some Tomos/Honda service notes. Trust your factory manual and platform guide over a generic list.
- Boot and wire seated; insulation not shorting to the frame.
- Kill switch / brake cutout stuck closed — unplug briefly to test, then reconnect.
- Coil ground clean; stator plate bolts snug; flywheel key not sheared.
- Test in shade: threads grounded to the head, boot on, pedal/kick — crisp blue snap, not a weak orange wink.
Puch points notes
From the Puch Maxi guide: clean the points, oil the felt pad, lube the flywheel cam, set points gap 0.016″–0.018″ fully open. Service the magneto before blaming the Bing. Plug gap on points bikes is often in the 0.020″–0.024″ range for B6HS — confirm for your engine.
Tomos CDI / points
The Tomos A35 / A55 guide calls out weak CDI/coil as a common “jets won’t fix this” failure — test spark before any jet changes. Specs worth knowing from that guide (starting points): spark plug NGK BR6HS (CDI) or B6HS (points); gap about 0.8 mm; points gap 0.35–0.45 mm on pre-CDI bikes.
Honda Express / Hobbit
Confirm spark, then immediately verify oil pump delivery. A bike that fires on starting fluid but was run without oil is a seize waiting to finish. See the Honda Express guide — these are oil-injected two-strokes, not premix Maxi clones.
After you have spark
- Spark OK but no start → won’t start (fuel + compression next).
- Starts then runs poorly → bogging or flooded Bing.
- Revs but won’t pull → clutch slip.