- Joined
- May 5, 2017
- Messages
- 657
![United-States Country flag](https://www.accessnorton.com/images/flags/shiny/32/United-States.png)
In the process of stripping down my Mk III, I noticed that transmission removal as detailed in section D7 of the manual, omits several steps. It also seems like more work then is really necessary.
SECTION D7 REMOVAL OF GEARBOX COMPLETE Though not normally necessary during overhaul, we recognize that circumstances may arise which make it desirable to remove the complete gearbox without disturbing the engine. However, the primary transmission must be dismantled fully. In these circumstances remove the rear three crankcase to engine plate bolts. Remove the rear wheel, and support the motorcycle by the lower frame rails on a strong box. Remove the centre stand. Completely remove the gearbox top and bottom mounting bolt and stud. Turn the gearbox anticlockwise in the engine plates viewed from right side. Force the rear engine mounting rearwards until the cutaway part at the bottom right hand side is clear of the crankcase. The gearbox can then be turned further and withdrawn horizontally from the right hand side. Only in isolated cases, will it be necessary to take out the front mounting main bolt. This is done to provide still further working space.
This method ignores the fact that the gearbox is held in place with two studs and 4 nuts, not bolts and nuts. The bottom stud will not clear the right hand exhaust pipe [at least on the Roadster]. It also ignores the fact that you can not rotate the gearbox shell enough, because the oil filter hoses are in the way. The engine is now hanging by the front mount and head steady. Potential for damage to the head steady rubbers if the engine is not supported from below.
I removed my gearbox case as listed below:
Remove the right side foot rest & brake hardware as detailed in section D3
Strip down the primary drive completely.
Remove the rear chain, or position the master link at the front sprocket and release the front sprocket from the chain.
Remove the kick starter arm
Disconnect the neutral light switch electrical connectors [ignored in the factory method]
Drain the engine & gearbox oil.
Disconnect the oil filter hoses at the filter. Withdraw the 2 hoses up, out from between the gearbox and the gearbox cradle.
Remove the upper gearbox mounting stud and nuts. Remove the nuts for the bottom gearbox mounting stud.
[the above steps are also necessary for the factory method]
Disconnect the right hand muffler from it's mounting.
Pry downward slightly on the right exhaust pipe for clearance to remove the lower gearbox mounting stud.
Rotate the gearbox shell anti clockwise [counter clockwise to North Americans] as viewed from the right hand side. Without the oil filter hoses in the way, you can now remove the gearbox from the right side.
Note: I did this after removing both the outer and inner gearbox covers. However, I suspect that their removal was not needed to remove the entire gearbox.
This method avoids having to put the bike up on a "sturdy box", removal of the rear wheel & center stand or disconnecting the engine from it's rear mount. I suspect that the oil filter hoses may also interfere with 1972 -74 models with oil filters. Comments please.
SECTION D7 REMOVAL OF GEARBOX COMPLETE Though not normally necessary during overhaul, we recognize that circumstances may arise which make it desirable to remove the complete gearbox without disturbing the engine. However, the primary transmission must be dismantled fully. In these circumstances remove the rear three crankcase to engine plate bolts. Remove the rear wheel, and support the motorcycle by the lower frame rails on a strong box. Remove the centre stand. Completely remove the gearbox top and bottom mounting bolt and stud. Turn the gearbox anticlockwise in the engine plates viewed from right side. Force the rear engine mounting rearwards until the cutaway part at the bottom right hand side is clear of the crankcase. The gearbox can then be turned further and withdrawn horizontally from the right hand side. Only in isolated cases, will it be necessary to take out the front mounting main bolt. This is done to provide still further working space.
This method ignores the fact that the gearbox is held in place with two studs and 4 nuts, not bolts and nuts. The bottom stud will not clear the right hand exhaust pipe [at least on the Roadster]. It also ignores the fact that you can not rotate the gearbox shell enough, because the oil filter hoses are in the way. The engine is now hanging by the front mount and head steady. Potential for damage to the head steady rubbers if the engine is not supported from below.
I removed my gearbox case as listed below:
Remove the right side foot rest & brake hardware as detailed in section D3
Strip down the primary drive completely.
Remove the rear chain, or position the master link at the front sprocket and release the front sprocket from the chain.
Remove the kick starter arm
Disconnect the neutral light switch electrical connectors [ignored in the factory method]
Drain the engine & gearbox oil.
Disconnect the oil filter hoses at the filter. Withdraw the 2 hoses up, out from between the gearbox and the gearbox cradle.
Remove the upper gearbox mounting stud and nuts. Remove the nuts for the bottom gearbox mounting stud.
[the above steps are also necessary for the factory method]
Disconnect the right hand muffler from it's mounting.
Pry downward slightly on the right exhaust pipe for clearance to remove the lower gearbox mounting stud.
Rotate the gearbox shell anti clockwise [counter clockwise to North Americans] as viewed from the right hand side. Without the oil filter hoses in the way, you can now remove the gearbox from the right side.
Note: I did this after removing both the outer and inner gearbox covers. However, I suspect that their removal was not needed to remove the entire gearbox.
This method avoids having to put the bike up on a "sturdy box", removal of the rear wheel & center stand or disconnecting the engine from it's rear mount. I suspect that the oil filter hoses may also interfere with 1972 -74 models with oil filters. Comments please.