As part of the Rugby Western Relief Road works in 2010 the bypassed part of the A4071 was renumbered B4642. This was previously indicated as the B4500, but has since been patched over when the council realised that number was a duplicate.
The road starts at the A426/A428 gyratory in Rugby town centre, showing forward destinations of Birmingham, Northampton (A45); and Leamington (A445); with Bilton as a local destination. The road runs down a hill through the area of Bilton, passing through signalised junctions providing access to recent housing developments. It runs through the 'village centre' of Bilton, before emerging into more rural territory and gaining an increased speed limit of 40mph.
At this point, we reach a roundabout linking to more new housing at Cawston Grange. From here the road bears left (which was straight ahead before the roundabout was built) and continue through Cawston on the Coventry Road, meeting the A4071 Western Relief Road at the Potford's Dam roundabout.