Checked the timing (as best I could - those 125s are a bugger for trying\nto get a static light on, and I couldn' shift the screw-in plate on\nthe generator cover, to access the crankshaft nut for turning the\nengine. So had to stick it in gear and turn it by hand.\n\nNew points installed, gap set, but... still misfiring. The midrange was\ncleaner with the choke on, so OK, it's almost certainly the carb.\n\nHm. OK, dig out the £30 used carb I bought, shove that on, and...\n\nbrmmmm.....\n\nPerfect. The cam that operates the accelerator pump is a bit clogged\nwith dirt, and doesn't return freely, but it runs perfectly now.\n\nI might just clean up this carb and leave it as is, or get the original\none (which is way cleaner externally) ultrasonically cleaned. There's a\nplace down the road that does it for nottalottamoney.\n\nA couple of hours in the garage well spent.\n\n The light just *will not* light no matter what you do to the points\ngap. Using a multimeter with an audible buzzer that should stop when the\npoints open doesn't work either - it just buzzes all the time.\nInfuriatingly, it works if you test the points off the bike. In theory,\nthe points are shorting out, but they ain't as it runs. I'll\ndouble-check with a fag paper, methinks.\n A round screw-in cover about two inches in diameter with a shallow\nslot in it. Bastard thing's stuck and I don't have an impact screwdriver\nwith one-inch blade, which seems to be the tool to shift it.