AJS 16M 1951

[dynamic]

I was carefull not to disturb crank or timing/cam sprockets ,I did wipe the mag shaft before replacing the sprocket maybe I disturbed the timing then ,
I have set the piston full advance (lever slack cable) at TDC then back 7/16 BTDC watching for the points to just start opening before replacing mag sprocket ,
I am getting a bang back through the carb ,I have the advance /retard at mid way point
if anyone could help me to re time motor I would be very gratefull

[Rex]

Grandma's eggs here, but you should wind the engine backwards a lot further, then winD forward until the timing point is reached. otherwise the lash in the gears will throw your timing out.
I usually start my bikes on just a little retard (rather than half) but all bikes are different and yours might need more retard.

[R]

then WIND forward

Aye, if all ye backlashes accumulate, then you may be in no mans land....

Lightly tapping the sprocket onto its taper is highly recommended,
or it may slip or move while you are tightening up the nut.

[cardan]

Double check that you have set the spark on the firing stroke, when both valves are closed.

Leon

[R]

Good call. ?
On a twin, you'd just swap the plug leads over.

But 4 stroke singles don't work like that.

[dynamic]

FINALLY STARTED before I was not allowing for gear backlash only setting to 7/16 BTDC, going further back then coming up to my gauge mark made all the difference

thanks to all who posted sound advice .

[dynamic]

kickstart has now decided to jam in upright position will not engage its solid just about an inch movement down before going solid ,it does spring back to resting position

anyone experiensed this at vall ?

[R]

Have you tried turning the engine/gearbox over, via the back wheel. ?
And seeing if that makes any difference.

It sounds like the kickstarter is not meshed or located correctly.
Let me find the Ajay booklet to refresh the grey cells, if someone doesn't chime in sooner.

[dynamic]

Hi R yes tried rocking in gear still no joy

[R]

If you google this problem, its exceedingly common with Burman boxes. !

The solution is to grind down the 1st tooth on the quadrant, and the 2nd tooth a bit.
Assuming you haven't reversed it from its original fitting.
Which can also be a fix.

Pulling the clutch in when this happens can also sometimes free things off.

[dynamic]

thanks for the input R I took the outer case off & and all looks in order ,HOWEVER now when I wheel the bike along I get a click click click from the g/box area ?
 this happens in both forward backward motion .............rather confused ?

[R]

So can you now kickstart it OK ?

Is that a fast click click, or slow
The chain contacting something could be a slow click,
but a fast one needs further investigation.
Even the tyre contacting something

Don't recall, is this bike new to you.
Some fettling is to be expected....

P.S That box is later than the CP expected for 1951 ?

[dynamic]

here are more photos dident load with previous post

PS. kickstart still solid .

[R]

Can you turn the box over at this point, using the back wheel.

The leading 2 teeth on that quadrant are not ground down at all.
This gives a rather brutal initial engagement, and they can jam.
Ground down a bit, they lead into the others, and swing into action. !

If that were mine, I'd get out the angle grinder with a thin blade,
and shave a bit off the 1st 2 teeth.  Keep the same basic tooth shape,
just shaved a bit, and no sharp edges left.  Easy does it....

[chaterlea25]

Hi All
When the outer cover is taken off the indent plunger and spring behind the selector drum pushes the drum outwards so partially engaging a gear inside the box hence the clicking !! It will be ok when the cover is put back on..
Make sure the ratchet gear on the gearbox shaft is working correctly and not worn out or broken.

John