gearbox rebuild problem

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I did the rebuild using mick Hemmings video as a guide. if fact did it twice,

with the inner cover on, the qudrant will move nicely through all the gears, with the outer cover it seems all i get is 1st, N and 2nd, when using the shifter on the shaft.

the box has all new bearings, shaft spin real easy with the inner cover on, the bushings looked good and so were not replaced. both shifter springs in the cover were replaced, both had much wear. the orings and seal were also replaced

i have not got any good pictures of the how the main spring under the Pawl engages the pawl and the bracket, but have assumed that the pawl is also engaged by the main spring.

from Micks video he is obviously able to hammer the shifter up and down through the gears

or is this just a matter of needs more rpm on the input shaft?

Help...
 
You do have to turn the mainshaft (input) relative to the sleeve gear (output) its been a while since I watched Micks DVD but if i remember correctly he has an old clutch centre on mainshaft an turns it as he goes through gears.
It another three handed job (At what point in human evolution did we think two was enough??) Get someone to turn mainshaft as you hold sleeve gear just tight enough so there is some drag on it then try the gears.
Putting oil in the box and giving it a good sloosh around may also help as would speed an vibration if it was in bike with engine running.
It maybe there is an issue but its worth trying the above if you haven't already.
 
850commando said:
i have not got any good pictures of the how the main spring under the Pawl engages the pawl and the bracket, but have assumed that the pawl is also engaged by the main spring.

https://www.oldbritts.com/gearbox_a.html

850commando said:
with the inner cover on, the qudrant will move nicely through all the gears, with the outer cover it seems all i get is 1st, N and 2nd, when using the shifter on the shaft.

Are you absolutely certain the quadrant is correctly timed to the camplate?
 
I refurbished my gearbox to the best of my ability (!) this summer, I replaced the gearchange ratchet spring (https://andover-norton.co.uk/en/shop-de ... het-spring) out of an excess of caution and had a similar experience to yours. I tried bending the new spring to make it engage with the pawl etc. correctly, but in the end I gave up and put the old one back in, as really it seemed fine. That did the trick! Maybe worth a try? To state what might be obvious, that spring does have to be the right way up – with the dog-leg at the bottom. Good luck.
 
LAB; i believe the quadrant is correctly timed with the inner cover on and bolted down, it will move from 4th to 1st without touching the inner cover at each end of travel.

based on the Old Brit photo i've got the springs in correctly, with the dogleg to the bottom, i put the old springs back in but this doesn't seem to affect it.

i will now try filling it with gear oil to see if that may do the trick...

thanks for the feedback.
 
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