Greetings,
My advice is to contact your local Groups as there should be somebody there to guide you on all of the aspects that you need to consider, not just the knowledge of the location of local lanes but the legality and suitability of their use too.
The problems are principally related to Traffic Regulation Orders which are applied by the Highway Authorities and National Parks to control vehicular access, in short to stop you riding just where you want. These TROs are brought in for safety so that the Authorities can undertake maintenance and repairs of the various routes, to protect routes from damage at times of bad weather or to totally stop access to recreational motorists such as ourselves from a political point of view
The UK is small and all land is owned by somebody, we do not have 'public' land in the same way as other countries.
We normally advise that folk do not ride the lanes on their own, again for a variety of reasons but principally for safety. If you do then do n't ride faster than your guardian angel can fly
I have put some routes up on the Viewranger website which you can take a look at or download for free, search Castleton, but you ride them entirely at your own risk, etc, etc., followed by more legal jargon and bull s##t
https://my.viewranger.com/auth/loginYou would be most welcome to pop over to our Manchester Group and we can guide you or just check out the whole list under the following link and visit a couple of others too;
http://www.trf.org.uk/find-your-regional-group/Good luck and I hope to meet with you sometime.
TTFN
Hugh.