What can I expect?

I've lost a few inches off my waist within the past few months I've been riding. In fact, I'm fitting in pants I hadn't ever worn, which were gifts from my parents from 2 years ago.

Will cycling restore 6-pack abs? I doubt it, but it will surely help you burn some fat and make it easier to achieve the "6-pack abs" goal.

Changes don't happen overnight. It's going to take you a little bit of time.

I'm just converting my winter bike to SS with a view to going fixed when I can afford to get a wheel built for it. I was wondering if it's possible to split the old Shimano cassette. the 12,13&14 rings are seperate but everything else is pinned together. Has anyone ever split one?
 
I'm not being tight - I've ordered an 18T but I just thought that if I could split the old cassette it would give me more options to try out for free.

There is nothing sacred about the cogs in a cassette ... I've cannibalized Shimano LX cassettes for specific cogs in the past ...
 
If the cogs are NOT on a spider (XTR, XT, DA, Ultegra), then you can simply remove the rivets/bolts which are holding the individual cogs together -- the heads of the rivets/bolts are either FLAT or will accept a 1mm (?) Allen Wrench ... if they are flat, then you will have to grind the heads off to split the cassette.
 
If you want to use a cog which is attached to the spider, then you would also need to fabricate a carrier from some sheet metal onto which you would mount the cog ...
 
If you are dealing with a Shimano Ultegra or DA ROAD cassette, since this is an interim implementation, why not just use the entire three-cog assembly rather than destroying it to access a single cog?
 
BTW. This may be stating the obvious, but if you are truly planning to convert to FIXED (vs. Single Speed), you will eventually need (a wheel with) a different rear hub.

Quoted post said:

why not just use the entire three-cog assembly rather than destroying it to access a single cog?

That had occured to me but I wanted it to look a bit neater.

Quoted post said:

BTW. This may be stating the obvious, but if you are truly planning to convert to FIXED (vs. Single Speed), you will eventually need (a wheel with) a different rear hub.

I'm planning on building my own wheel so I will be looking at hubs soon. I'm going to butcher my old Mavic CXP22s for the rims. Any recommendations for budget hubs?

I'm off to look at second hand steel frames later. Can't wait to get started.

Quoted post said:

I'm planning on building my own wheel so I will be looking at hubs soon. I'm going to butcher my old Mavic CXP22s for the rims. Any recommendations for budget hubs?

If you don't need a Flip-Flop hub, then you can let your budget be your guide ...

I chose to use a Campagnolo Nuovo Record rear hub for one SS rear wheel because it was what I had ... so, that certainly fit MY budget at the time.

Of course, you need to be conscious of the spoke hole count of the hub you use ...

Otherwise, almost any older hub which is designed to use a Freewheel will do -- a vintage Shimano hub is certainly a good option.

If you want a Flip-Flop hub, then in descending order: Campagnolo, Shimano, Miche, and Formula are three brands to consider -- these will all be TRACK hubs with 120mm spacing.

If you need a hub for a wider frame (e.g., 126mm, 130mm, and 135mm) then Surly is probably the best option.

If the wheel has a solid axle, the flange spacing doesn't really matter ... normally, mounting the chainring on the inner shoulder of a ROAD crank's arm will proivde a pretty good chainline.

BTW. A steel frame can be respaced DOWN to 120mm.