Hi Bilge Rat,
If your bike needs the pictured
cartridge bottom bracket, the two numbers are usually 68 or 73 - mm for the shell width, and 113 or 118 mm for the axle length - so the pictured one is 73mm shell and 113 axle length. On the left of the picture the threaded part is a plastic insert that screws in to the non-drive side of the frame
right hand thread, the remaining unit, which is a sealed unit containing axle, bearings, seals and grease, screws into the drive side
Left hand thread.
It is removed with a special splined tool that sits into the slots that you can see on the left of the picture.
However, from your comments
i have only got the shaft 1 side and the bearings out
your bike doesn't use this system. I guess you removed a locknut from 1 side of the frame, and then unscrewed the cup, and pulled the axle free, leaving you with either a handful of dirty balls (!), or 2 caged races (bearings held in a metal frame to reduce incidences of chasing bearings all over the workshop).
If it's the latter, the bearing should be very easy to replace, either from Halfords, a local bike shop or a bearing supplier. You also need to check the bearing surfaces on the cups and axle for excessive wear. If necessary these can also be replaced - not sure about Halfords for this, bike shop should be able to help.
Clean everything up with degreaser (petrol, brake cleaner, white spirit or purpose made degreaser will all work), dry off, regrease with a fairly thick grease and reassemble. Tighten the cup down all the way, then back off a fraction of a turn and put the locknut back on, job done!
