Gear selector shaft replacement

Yes, could be the drive shaft that is broken or the splines are stripped at either the engine or lower unit. Remove the lower unit to check.

If the selectors are in neutral and you can't get third gear check that the selector shaft is not seized and the gear is free to slide on the splined shaft.

sheering box nut shaft will be 120 ft/lb tie rod joints are 30-40ft/lb

the lever itself? is it the type with the 10mm bolt going through the lever (into a splined shaft)?
if so then either the thread's gone in the bolt/lever or the splines have gone on the shaft, otherwise it's the gear selector shaft/bearings within the box.
Hope this helps

only thing i can think of is 1/2 shaft splines.....jack up car(both wheels)and spin one,the other should move.....sorry if wrong....

Auto boxes are best left to professionals but there are some things you can do 1) check that the selector rod from beneath the gear shift to the gear selector on the side of the gear box is correctly adjusted, 2) make sure that the transmission oil is at the right level, new oil can be added via the dip stick tube. If you are adventurous and are able to remove the gearbox pan you might be to see evidence of the gear box damage, metal shavings etc. If you can remove the gearbox you may be able to replace a sheared splined input shaft (indicated by a an engine that is running but that will simply not engage gear). Anything repairs beyond this should be left to an expert or simply replace the gearbox

Before stripping the gearbox be sure it isnt just the gearshift pedal rotating slightly on its shaft. The splines on the shaft will ruin the pedal if its not tightened correctly.
Otherwise it could be the gear selector mechanism. The spring on the shift claw or detent arm may be broken.
Check it out by rotating the rear wheel whilst the bike is turned off & on its main stand, then select each gear by hand with the pedal.

Good Luck
Hope this helps.
(If it does then please mark this as 'useful')
Ride Safe
Bike-Doc

its in the gearchanging mechcanism,worn,, slipping,,loose bolts on selectors splines worn or broken the pegs on the selectors broken so not engaging with the slots in the gearchanging disc

check the linkages (rods connecting stick and gearbox) my e2000 is also stuck in third mechanic friday then ill post my discoveries

Hi Alex Iam not too sure but I think this model had a neutral switch fitted that stopped the bike from starting in gear , and displayed a light on the clocks when the bike was in neutral .
If as you say the bike is jammed in first this is probably the cause
the jamming sounds abit more serious ?.. you may have bent the selectors and this will mean a gearnox stripdown , it is even possible you have damaged the lay shaft if the bike was travelling when you came off this would also mean a box strip down .
I dont think there is an easy answer to this one Alex loks like you will have to take the engine apart to fix this one ( one thing did strike me I had an old BSA that I slid on the gear shaft and did the same thing stuck in first turned out I had bent the gear shaft removal of the pedal and gentle tapping freed the gears off and I was able to use the bike again ? it may help I cant be sure be careful not to damage the case or the splines I used a small lump hammer and a block of 4x 4 against the shaft .. I also put a wedge behind the shaft to stop damaging the rear of the box housing ) hope this helps Regards vortash