Kick Start not returning to position.

[Peter Waller]

I have just rebuilt my gearbox on my 1974 850 Commando because it was jumping out of first but I did not find a problem. There was excessive play in the shaft the kick start is attached to so I shimmed this as recommended with a rear isolastic shim. I fitted a new kickstart spring as well. Anyway the gearbox is back on the bike and primary all built up so I went to kick it over and it is hard to kick over and the kickstart does not return to position unless I pull it up....any ideas please? All was good until I took the gearbox apart so it cant be bushes or anything and I did not change any bearings. Has shimming it made this happen? I can select all the gears all though difficult as I have not started the engine. Thx for any help in advance.

 

[concours]

I have just rebuilt my gearbox on my 1974 850 Commando because it was jumping out of first but I did not find a problem. There was excessive play in the shaft the kick start is attached to so I shimmed this as recommended with a rear isolastic shim. I fitted a new kickstart spring as well. Anyway the gearbox is back on the bike and primary all built up so I went to kick it over and it is hard to kick over and the kickstart does not return to position unless I pull it up....any ideas please? All was good until I took the gearbox apart so it cant be bushes or anything and I did not change any bearings. Has shimming it made this happen? I can select all the gears all though difficult as I have not started the engine. Thx for any help in advance.

That shim needs to have the ID opened up a bit, otherwise it falls on the radius of that kickstart shaft. No doubt would cause a symptom like you're reporting.

 

[marshg246]

I have just rebuilt my gearbox on my 1974 850 Commando because it was jumping out of first but I did not find a problem. There was excessive play in the shaft the kick start is attached to so I shimmed this as recommended with a rear isolastic shim. I fitted a new kickstart spring as well. Anyway the gearbox is back on the bike and primary all built up so I went to kick it over and it is hard to kick over and the kickstart does not return to position unless I pull it up....any ideas please? All was good until I took the gearbox apart so it cant be bushes or anything and I did not change any bearings. Has shimming it made this happen? I can select all the gears all though difficult as I have not started the engine. Thx for any help in advance.

Shimming, if right cannot cause that. There must still be some endplay. If you haven't already, read this: https://www.nwno.org/resources/OldBrittsWebsite/gearbox_a.html

 

[htown16]

As mentioned the id of the shim needs to be opened up a bit to get proper freeplay. Use a barrel bit in a dremel.

 

[Peter Waller]

Will take the cover off and have a look. There is no end play on the shaft so perhaps the shim was to thick or it is tight on the shaft. Will investigate.

 

[kommando]

You need some end float, suggest you aim for 5 to 10 thou.

 

[ludwig]

Will take the cover off and have a look. There is no end play on the shaft so perhaps the shim was to thick or it is tight on the shaft. Will investigate.

Before taking the cover completely off, loosen the 5 screws half a turn and see if that frees the kick. A sticky kick can also be caused by the kick spring rubbing against the outer cover. A thicker gasket can solve it, and you won’t have to remove the inner cover.