OK the photo below may not be very exciting but bear with me!

told you but if you want a good basic guide to working on bikes from the same era as the mighty grifter (really mid 60s to mid 80s at a guess) for beginners this could be for you.  there are some great step by step picture guides and exploded diagrams (i have posted a couple on headsets and twist gear controls).  You can pick up one of these dead easy at a car boot for 10p!  But don't take my word for it have a look when you see one.  also contains 100s of other how to mend/repair guides from boats to books.
The instructions include:
Valves and inner tubes - mending a puncture
Wheels - fitting a new rim tape/refitting a tyre and tube/renewing spokes and straightening a wheel/checking and replacing bearings
Chains - testing a chain:fitting a new one/cleaning a chain
Cable brakes - adjusting brakes and fitting new blocks/mending a broken cable
Rod brakes - brake adjustment
Hub brakes - fitting a new front shoe
Front forks - checking and replacing bearings
Bottom bracket - checking and replacing bearings
Crank assembly - adjusting and replacing cotter pins
Hub gear cable - renewing a trigger control gear cable/renewing a twist grip control gear cable
Derailleur gear cable - replacing a gear cable/adjusting a five speed gear/removing a derailleur gear rear wheel/adjusting a ten speed gear
Freewheel sprockets - replacing a sprocket
Fixed wheels - removing and replacing a fixed wheel
pumps - fitting a new washer
Coaster hubs - renewing the bearings
Handle grips - fitting new grips
Pedals - renewing the bearings/replacing the rubbers
Handlebars - replacing a tape
Mudguards - fitting new mudguards
Dynamos - checking a tyre driven unit
Dynohub lighting - testing and cleaning/wiring for plastic lamps/wiring for metal lamps

I have their Household hints and handy tips book. Its got some wonderful advice in it also.