I open a topic for special tools that is good to have, please contribute with tips and pictures of what you have made or acquired.
A couple of tools that can be good to make, is dedicated pullers for the mag gear, both crankshaft gears and clutch hub.
The cam cover screws is made a bit special, the slit is machine sawed so a common wedge blade screwdriver slips easily. The blade tip needs to be ground parallel and rounded. Good fitting and full width, that's important, so a dedicated screwdriver for that is needed in the tool roll.
The end cap on the oil pump can be a bear to loosen, it is LEFT HAND threaded and the slit is also machine sawed so a flat, rounded, full width, perfect fitting, very hard steel blade needs to be ground for it with a place for a spanner for turning and sturdy handle for pushing in order to avoid slipping. A bit of heat can help loosen it up.
Special spanners for the intake and exhaust nut is good to have in the tool roll, they might have to be retightened on the road.
Key spanners for the rear sprocket and drum brake, and steering head adjustment, instead of hammer and chisel is giving pro vibes to the surroundings, so does a pin key spanner for the big nut behind the sprocket on the gearbox. The thin bearing behind that nut should be replaced often, really at every chance you have because it is losing specifications rapidly.
A tin plate spanner is needed to get in between and adjust the rear wheel bearing on those with loose ball bearings. The bearing play has to be readjusted every time the wheel axle is loosened.
What more... the funny looking (overengineered) tool in the picture right corner is a keeper for the clutch hub, when torquing the center nut. In the middle of the handle is a simple clutch hub puller. 2 holes for long screws that threads in the clutch hub and in center a push screw. For those hubs without threaded holes, a clamp might have to be made.
The blue handle spanner is a homemade spanner for the inner big nut in the gearbox for the clutch basket. I recommend to buy that spanner readymade from KIWI, Greer or Stark, maybe Walkers have it, as I found it difficult to make the jaws stabile enough in that cramped area, they tend to open and slip. The distance tool prevents the spanner from slipping.
And close to the clutch basket, a pin key spanner for the large gearbox outer nut.
I tried that oil filter tool to keep hold of the crankshaft gear when tightening the nut, but it wasn't successful. I cut a ring of a steel tube that fitted loosely outside the gear and inserted in the gear teeth 5 broken drill bits, that I then spot welded to the ring on both sides. Then I welded that ring to the other end of the clutch tool.
My most important helper is Locktite. Locktite on every single threaded part all over the motorcycle with just a few exceptions. Medium and strong and penetrating and thread seal for the intake threads. Lipstick locktite is the best thing since cold beer to have in the sidebags.