
Originally Posted by
Marco
40 years ago bikes had loose ball bearings in the bottom bracket cups, and some had cages to hold the bearings together. If the cage split then this could cause a sudden slackness in the area; Tony Doyle lost a major British race when this happened to his Campagnolo (NB Graham) bottom bracket.
I haven't seen a bottom bracket with loose ball bearings for over 25 years, as they've all been sealed bearings - even on cheap bikes. It may be that yours is loose bearings, but I'd doubt it.
Opening up the bottom bracket is quite difficult, and there is a special tool which will depend on the model. This actually might be a bike shop job. If you intend to do your own bike mechanics, (which may be advisable because of your locality as much as the cost), it would be worth buying the relevant tool. Graham will hate me for saying this, but one of the reason I stick with Shimano is for compatibility - I have the removal tool and it also works for the very cheap far East products which copy the design