suggestions for uncommon tools

i'm finally in a place where i can start grabbing tools that i will need to repair my 1982 kz 750 ltd. i've seen videos about the motorcycle mechanics tool box so i have a decent idea of most tools i will need but i was wondering if anyone had any suggestions for more unique tools or maybe costly but worth it tools that have helped them with working on older bikes? really any advice is useful advice here. thanks

JIS Screwdriver set.
 

Fiberglass pens for cleaning electrical contacts 

Headlamp

Good quality wire strippers and a selection of bullet connectors

These...

I would advise you buy as and when you find things you need. It’s easy to get “ the fever” and spend a small fortune on things you will never use

Wookie58 wrote:

I would advise you buy as and when you find things you need. It’s easy to get “ the fever” and spend a small fortune on things you will never use

Very true, but JIS screwdivers are a must. 

Here's a basic list with a few bigger tools that really make life easier.

Two good sets of metric combination wrenches 
1/4 "- 3/8"- 1/2" sockets in 6 and 12 point, standard and deep with plenty of various extensions 
inch pounds torque wrench 
a selection of hammers including deadblow and soft
a selection of pliers and vise grips 
steel punch set
brass punch set 
multi meter 
electrical connectors/soldering gun with electronic solder and heat shrink 
cordless impact gun with a selection of bits and drivers 
compressor and air tools 
motorcycle lift table 
solvent wash tank, preferably petroleum base solvent 
a couple of scissors jacks
 

Define "uncommon". Or more so, define the tasks You're looking forward to completing? I'm with Wookie on this, don't just willy-nilly empty your wallet. Which category or system of machine needs attention? Some things are better left to professionals, like a valve job. Why would you spend 4-700USD on seat cutters when you can have the whole job done for maybe 250USD. 

My JIS screwdrivers are a great investment but when I think about the tool I should have had in the beginning....I think it's my torque wrench.  Would have saved me a lot of grief when putting engines back together.  I don't use it very often but it has been absolutely necessary when I did.  Guessing at proper bolt torque is a mugs game.

Tool junkie here.  Must resist writing an epic tome...

Metric thread chaser set and / or thread file.
A ft. - lb. torque wrench and a in. - lb. torque wrench.
If building spoke wheels, a spoke torque wrench.
When working with points, we've come to prefer an analog dwell meter.  Conversion charts are available to convert for wasted-spark ignition systems.
A known-good 12v battery to power a timing light alone.  Ripple from crude DC rectifiers can falsely trigger some timing lights.
If working with 5mm (aka 4.9mm) barrel connectors, a good plier-type (not ratcheting) crimper that makes the conductor crimp and insulator crimp individually.
An analog VOM.  DMM's are convenient but, being able to observe instantaneous needle deflections that can't be resolved by a DMM display can ease electrical troubleshooting.
A DMM that has a sounder to indicate change of state audibly.  A sounder can often substitute for seeing needle deflection of an analog meter.
If you have access to sufficient air volume and the patience to deal with the hose, a 3/8" air ratchet.  Careful of the torque one can produce.
NO-OX-ID "A-SPECIAL" Electrical Grade contact grease to keep those pin & barrel connectors um..., connecting.
EDIT: to add an impact screwdriver.  We have a decades-old Lisle that came with JIS bits before JIS was a well-known thing.  They're still available.  Vessel makes a good one too, with JIS bits.
Those hit the high spots.  Gotta quit while your wallet is still healthy.

Good Ridin'
slmjim & Z1BEBE

fork tool for disassembling the fork innards in case the bottom allen bolt is stuck >> LH-threaded 1/2" bolt & nut w 3/4" head. use w ratchet wrench and socket w long extension to hold the inner cylinder while unscrewing the bottom allen bolt. note: bolt-head should accept a 3/4" or 19mm socket. 19mm is the size of the inner cylinder head. some guys just weld a nut to the end of a bolt. 
ps: from the diagrams the 750Ltd should use the same tool as the 650csr.   ....  ...... image posted previously on kzr a while ago.

not sure how a spark plug socket would be any better. see following comment. a bolt & nut was cheap and I don't have a spark plug socket to try. ha ha.

 

H1Vindicator wrote:

fork tool for disassembling the fork innards in case the bottom allen bolt is stuck >> LH-threaded 1/2" bolt & nut w 3/4" head. use w ratchet wrench and socket w long extension to hold the inner cylinder while unscrewing the bottom allen bolt. note: bolt-head should accept a 3/4" or 19mm socket. 19mm is the size of the inner cylinder head. some guys just weld a nut to the end of a bolt. 
ps: from the diagrams the 750Ltd should use the same tool as the 650csr.

 

A spark plug socket, the type with a hex on the bottom, fits the damper rod.  Use a long extension and install it backwards, so the hex is down.