In reply to Stone Muppet:
Hi, I've lived on the Roaches for the last 27 years and there aren't many legal routes. There is the route you've already mentioned from the Cat and Fiddle through 3 shires head and eventually coming up the very far Skyline end of the Roaches from the valley bottom but any paths above the road are all footpaths and out of bounds for any cycling. with the exception of the couple of km of bridleway that cuts between the Roaches and Hen Cloud but some of that is permissive...
The best and VERY muddy (dark) Peak routes are indeed in the Hope/Edale area, far more challenging and faster than anything the Roaches can offer...And I really can't see the appeal of the stuff around Macc Forest it's all a bit short and over a bit quick...
Hope this helps..