If you photocopy your OS maps it may be worth considering going digital - I've been using Anquet
mapping for some time & the prices have tumbled over recent years. Central England (1 of 10 regional sets) at 1:50k, for example, is now £15 (£18 for High Definition) & covers 19 paper sheets (by my reckoning - "Equivalent coverage to Landranger® sheets 108-111, 117-120, 126-129, 138-140, 149-152. Includes the Peak District, the Midlands, the North Cotswolds and the Malvern Hills."). The whole GB 1:50k set is currently £100. If you get on their mailing list then there are often special offers, often half price.
The program lets you print sections to scale (not necessarily the native scale of the map - I will often print 1:50k route maps out at 1:25k for walks if I don't have the 1:25k mapping for that particular area). The other thing that may be useful for longer tours is that you get a copy of the 1:250k mapping for the whole OS GB area, which is probably good enough for many cycle trips (I've grabbed a section as an example). It seems to have virtually all the passable roads outside urban areas.
You may even be able to get a copy by creating an account but not buying anything as the 1:250k mapping is now part of OS's free to use Opendata* - I don't know as I already have an account & have bought maps.
If you have an Android Smartphone or tablet or an iPhone/iPad you also have the option to use the mapping on them.
Other map suppliers will no doubt have similar, maybe better, offerings - I'm just giving info on the one I know.
(*If you have deep pockets, short arms & reasonable image computer skills you can get the 1:250k mapping free direct from OS
- it will cost you nothing more than the price of an email address to give to them for them to send you a download link. For that you get a 153MB zip file which opens up to a set of files including 56 .TIF image files, one for each 2 letter grid area, plus other files to do other clever things with the maps if you have the skills.)