speeding of traffic along the B489 Tring Road

Please would it be possible for a mobile speed camera to check on the speed of cars along the B489 Tring Road. I am very concerned about the speed limit not being inforced along parts of this windy B road, especially where residents are pulling out onto this road. Some vehicles are definately not keeping to the 60mph limit.
Thank you.

Yes..a "permanent speed camera" is on the Dunstable side of the dual carriageway.Once drivers are past it they accelerate onto the dual carriageway. The speed limit on dual carriageways I am told is 70mph. It is obvious at times that by observation they are doing close to this speed as they pass the residential/commercial/farming entrances at the "The Plough end" of the Tring Road.  I have written to our MP Andrew Selous who has been in contact with the Highways Department. I have had a reply that no further plans for erection of warning signs/speed signs/hidden entrance signs are forecast- in fact some of the damaged posts with missing signs will be removed and not replaced.
Drivers have been seen overtaking cars turning into entrances along this road with near misses with traffic coming in the opposite direction!! Has anyone accident statistics for this area?

Speeding along Tring Road between Gliding Club entrance & Harling Road Roundabout - can someone advise
1) Since the powers(local authority)cannot do this because of lack of funds -providing that they are compliant with designs used by Highways Agency can a member of public erect traffic warning signs in the verge at the side of the road? There are hidden entrances along this road where all that remains of the old signs are posts!
2) how mush does it cost to install a speed limit sign like we have in Eaton Bray? Also for any roadside sign?
3) why are the "across road speed tubes" only surveyed at the top Dunstable end of Tring Road?