Need new chain

Wow, you really have no business working on your own bike, or even being allowed out of the house on your own. Spend a couple of days using the search on this site, and google, before coming back with more questions.

Youtuve has the answer, I see that I will need an additional cog, and I suppose it has slightly different thread as it sits on differently. I don't see why you have to be nasty about it though. I am just in a bit of a rush as I want this back on the road tomorrow.

Is it a bad idea to sock the whole freehweel in decreaser? I assume it is but its going to be tricky to get all the thickn gunk off it otherwise.