Gearbox

i am looking for some advice  my norton commando 1974   with the spark plugs out i can turn the engine with the kickstart  but with plugs in  it does not catch inside the gearbox the spline on the shaft and kickstart is good

Sounds like the pawl inside the k/s shaft is worn or it's small spring has rusted out and broken. Both covers need removal and even if you have a manual and are capable take a look at this site http://www.oldbritts.com/ob_start.html go to Tech articles - Gearbox etc. Lots of pics including one of a worn pawl.

Sounds like the pawl inside the k/s shaft is worn or it's small spring has rusted out and broken. Both covers need removal and even if you have a manual and are capable take a look at this site http://www.oldbritts.com/ob_start.html go to Tech articles - Gearbox etc. Lots of pics including one of a worn pawl.

can the gearbox be overhauld in the frame

Yes it can Stewart but if you want to totally strip you have to remove the clutch anyway. Once that is off it's not a lot extra work to pull the engine sprocket and inner primary etc. D/S bearing removal will take a little heat and they can be knocked out with taps on the casing. Of course it's easier if the box is out and since you dont have a Combat with the rear breather it should be possible to remove gearbox bolts and rotate 45 deg to slide out of the RH side.  Sometimes the rear engine bolts/studs need to come out and the cradle and swingarm moved back to let the box clear the rear of the crankcases. Just make sure you loosen the drive sprocket nut before the drive chain comes off.

Previously wrote:

Yes it can Stewart but if you want to totally strip you have to remove the clutch anyway. Once that is off it's not a lot extra work to pull the engine sprocket and inner primary etc. D/S bearing removal will take a little heat and they can be knocked out with taps on the casing. Of course it's easier if the box is out and since you dont have a Combat with the rear breather it should be possible to remove gearbox bolts and rotate 45 deg to slide out of the RH side.  Sometimes the rear engine bolts/studs need to come out and the cradle and swingarm moved back to let the box clear the rear of the crankcases. Just make sure you loosen the drive sprocket nut before the drive chain comes off.

just like to thank you keith  for your kind reply