Since most of us in NSM work primarily on largeframe motors, when I built my first smallframe motor, I watched a number of youtube assembly videos and documented the assembly sequence, since there's really only one way to get it all together correctly.
Having done that, I figured I should share it here for posterity.
If this was a recipe blog, I would open with several pages about the history of the smallframe, my family's connection to it (my parents had a 50S in the 1960's that my dad used to commute to grad school. It was named "Murgatroyd."), etc.
But I'm just a snarky mechanic, so instead, here we go...
Starting with clean, empty cases...
Install...
1. Engine mounts
2. Kickstart buffers
3. Gear shift wishbone
4. Fly side main bearing
5. Fly side lay shaft(?) bearing
6. Clutch side
1. Main bearing
1. circlip
2. seal
7. Clutch side clutch bearing
8. primary gear
1. circlip (on basket shaft)
9. Kickstart quadrant
1. return spring
2. clutch basket base plate
1. wavy washer
2. spiral spring
3. kickstart gear
10. Axle+gear stack
11. xmas tree
12. Crankshaft
1. Pull into clutch side
Apply gasket sealer+case gasket & close the cases
Check for crank movement
Apply Case bolts
1. little end bearing
2. wrist pin & piston
3. piston circlips
4. base gaskets (if any)
5. cylinder w/ exhaust stub already installed
6. head gaskets (if any)
7. cylinder head
8. reed block+manifold
Clutch Side
1. crank spacer
2. drive gear
3. drive gear washer
Clutch
4. clutch basket
5. clutch base plate w/ springs
Compress clutch
6. plates
7. top plate
8. pressure plate
9. clutch cover
Rear Hub
1. Brake base plate (with shoes & cam pre-installed)
2. rear hub
3. rear hub nut
Final big parts
1. Stator+flywheel
2. Kickstart lever
3. Carb
4. Exhaust
Good reference video:
Having done that, I figured I should share it here for posterity.
If this was a recipe blog, I would open with several pages about the history of the smallframe, my family's connection to it (my parents had a 50S in the 1960's that my dad used to commute to grad school. It was named "Murgatroyd."), etc.
But I'm just a snarky mechanic, so instead, here we go...
Starting with clean, empty cases...
Install...
1. Engine mounts
2. Kickstart buffers
3. Gear shift wishbone
4. Fly side main bearing
5. Fly side lay shaft(?) bearing
6. Clutch side
1. Main bearing
1. circlip
2. seal
7. Clutch side clutch bearing
8. primary gear
1. circlip (on basket shaft)
9. Kickstart quadrant
1. return spring
2. clutch basket base plate
1. wavy washer
2. spiral spring
3. kickstart gear
10. Axle+gear stack
11. xmas tree
12. Crankshaft
1. Pull into clutch side
Apply gasket sealer+case gasket & close the cases
Check for crank movement
Apply Case bolts
1. little end bearing
2. wrist pin & piston
3. piston circlips
4. base gaskets (if any)
5. cylinder w/ exhaust stub already installed
6. head gaskets (if any)
7. cylinder head
8. reed block+manifold
Clutch Side
1. crank spacer
2. drive gear
3. drive gear washer
Clutch
4. clutch basket
5. clutch base plate w/ springs
Compress clutch
6. plates
7. top plate
8. pressure plate
9. clutch cover
Rear Hub
1. Brake base plate (with shoes & cam pre-installed)
2. rear hub
3. rear hub nut
Final big parts
1. Stator+flywheel
2. Kickstart lever
3. Carb
4. Exhaust
Good reference video:
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