Ask to change the speed limit
A review was carried out between 2002 and 2012, there is no longer any funding for changes to speed limits.
If you want a speed limit change you need to get support from your local parish/town council. There is a fee to cover the work required and it depends on how complex the changes are.
20mph speed limits
In January 2013 the Department for Transport issued revised speed limit guidance, which includes new advice on 20mph speed limits.