Hitchcocks Forum

Dear All, I have recently refitted my recon Magneto and with fresh fuel and oil was hoping she would fire up....not so unfortunately. She has a spark and i have popped some fuel down the plug holes but the most i can get is a very occasional pop. I haven't done anything with the ignition timing but reading into it, looks like every time the Magneto sprocket comes off the timing needs to be adjusted, can you more experienced people tell me if im barking up the right/wrong tree? Also if this is the case, can you give me an idiots guide to checking the timing? Thanks in advance

Yes Connieowner, every time the sprocket is removed the ignition needs re timing.

Oops sorry missed the "idiots guide bit",----- set one cylinder at 7/16" before top dead centre with the advance/retard lever set on full advance then turn the magneto forward until the points are just and only just beginning to open, (ensure the points are set to the correct cylinder) then tap the sprocket on the taper and tighten the nut, re check that the timing is correct and has not moved if OK, start bike, if not OK do it again.

Good grief the heat is affecting my Brain, also ensure both vales on the chosen cylinder are closed, IE compression stroke.

Cheers Dennis, some daft questions; is there an easy way to know both valves are closed? How do i tell if the points are set to the correct cylinder? Finally, is the fully advanced position on the lever towards you or away? Thanks again.

Connie owner,
Simple method, make sure the rear wheel is off the ground, plugs out, use the kicker to wind the motor over and with your finger over the plug hole you will feel/hear when it starts to come up on compression stroke. Use the neutral finder to flick it into 4 gear, then with a drink straw down the plug hole you rock the rear wheel FORWARD till the piston hits TDC, mark the drink straw at the plug hole and then mark it 7/16th higher and then wind the rear wheel BACKWARDS until the higher mark is level with the plug hole as per the first mark. Then follow Dennis's procedure

As Norm says to find compression stroke, if the handlebar lever moves the cam in the opposite direction to the mag rotation when pulled back that is full advance, if it moves it in the opposite direction when pushed forward then that is full advance, different mags can vary. ------ To verify which is the correct opening position for the selected cylinder look at the spark plug for that cylinder whilst connected to the H.T. lead and the body touching the engine turn the mag forward until this plug sparks then the points are on the correct cam turn back until points close and set as previously stated.

Thanks gents, i shall give it a go!