Oh why oh why did I bother with this bike...

[cyberknight]

In case other people come looking here, a crankset is the cranks and a chainset is the cranks and chainrings combined.

I suggest this assertion is not true. Please quote your source. The 'industry' fits cranks at 170/172.5/175mm depending, to an extent on the size of the frame.

Just do what other helpful posters have suggested on your other thread (linked to by @vickster ) above: buy a ST compact (50-34) 170mm ST chainset at Spa Cycles (this one: https://www.spacycles.co.uk/m8b0s109p45/STRONGLIGHT-Impact-Double ) (@PpPete ) and one of their BBs (correct spindle length) at the same time. Your current BB is probably suffering from neglect anyway so a replacement would be cheap (£20) and sensible (anyway).
Don't get fixated on a 52t ring. If you want a longer gear, procure a cassette with an 11t sprocket: eg 11-30.
Edit: Thank you @Moderators for merging the two threads.

if its subway you will be doing well to push more than a 48 anyway at any speed, when i had mine i was trundling along at about 19 mph or so on a 48 on 26" tyres and that is what i found sustainable

 

[GoatBeard]

The crankset is £48, plus the BB £20, BB Socket £10, £83 in total for the parts inc delivery. I can't help but think stuff that, total false economy for a donkey bike that's only purpose is short trips to the shop and back without getting nicked.

So plan of action is to wheel it down to the LBS and see if they can perform a miracle and simply straighten up the cogs end of.

 

[Blue Hills]

What's the reason for wanting to change the crank set/rings etc? In all the years I've been cycling, I've never changed a crankset/rings because they are worn. I've changed many for different reasons - weight, number of teeth etc, but never because they were worn. Rings have always lasted until the bike was replaced.

This surprises me. Do you use particularly tough/expensive chainrings?

 

[Sharky]

It is true that I've never changed a chain ring because I thought it was worn. My first bikes had steel rings and I started racing using a Williams c34 steel ring. These probably didn't wear at all.

I've got thru loads of chain rings to change the number of teeth. Triples have been replaced by doubles and then singles etc.

Over the years have used TA, stronglight and recently raceface n/w rings. A few years ago I was hitting 7k pa, but since retiring, milage is nearer 1k to 2k pa. Probably don't do enough miles to reach a worn ring before I decide to change for other reasons. Having 4 bikes in use must extend their life as well.
Cheers