I want to put a freewheel on the other side of my hub. Some basic questions: can I just thread it on by hand or do I need a special tool? Which side of the freewheel is supposed to face the hub (the flat side or the side with the raised plastic)? It says it fits 1/8 or 3/32 chains; how can I tell which of these are on my bike? Can I just use chain lube as the grease or do I need some of that green grease prior to installing it?

Thanks for the help

1. Yes, thread it on by hand, riding it will tighten it as much as it needs to
2. flat side against the hub. there is a tool to remove it and it has four prongs, so the side the tool will fit into has to face outward.
3. if it fits either 1/8 or 3/32 then technically it is a 3/32 free wheel. Some chains have their size stamped onto some of the links otherwise, it is kind of hard to tell with an untrained eye.
4. the green stuff would be appropriate, but I put on and took off plenty freewheels on my BMX bikes for years with just a little WD40 (not advocating it, but it is possible if you are in a pinch)

you can thread it on by hand. you thread it on in the same direction it engages (so that your wheel will turn when you pedal). if it says 1/8 and 3/32 chains it's 3/32 and you probably should use a 3/32 chain. lube is probably better than nothing but you should probably use grease.

edit: too late

rub a bit of grease.. not chain oil.. onto the threads and just thread it on by hand. if you have a chain whip i would tighten it down mroe but you will get most of the tightening down once you get riding and get in a good climb or hold the brake and torque it down. Im not sure i've seen any freewheels with plastic? but the smooth side goes towards the hub and the side with the indents for the tool go on the outside..or else you'll never be able to pull the thing off.