quick trip up the A46 to the M4.
The problem with bath (and saltford) are the roads in and out. The 46 is a bus lane and gets very congested, but it's nothing compared to the route in from Saltford. The A4 into bristol is the worst traffic hot spot in the city (certainly from the ring road into brislington).
I'm a N.Bristoler and it's nice but there are no local trails worth speaking of and getting to ashton means going through the centre (although the cycle track is pretty quick) up park st and over into clifton. Access to the M4 is perfect from here though, there's a lovely back road which avoids hambrook. Iron acton is very nice (small village, great pub, winterbourne academy catchment, bristol commutable by bike) N.Bristol wise; we're looking at frampton cotterell, coalpit heath, winterbourne, pucklechurch. South bristol wise; westbury on trym, Pill, Wraxall? I don't that side too well.