24 September 1978 at Honeybourne
| 500cc | 350cc | 250cc |
| 1- Brian Webb | 1- Gerald Short* | 1- Mark Wadsworth* |
| 2- Tony Steggles | 2- Rob Smith* | 2- Richard Wakeling* |
| 3- Simon Wigg | 3- Roland Duke* | 3- Martin Hagon |
| 4- Graham Hurry | 4= Graham Hurry | 4= Tig Perry |
| 5- David Spain | 4= Tig Perry | 4= Brian Webb |
| 6- Chris Pidcock | 4= Mark Wadsworth | 6- Dave Brown |
| RH Sidecars | 500cc Sidecars | |
| 1- Steve Smith & Trevor Pye | 1- Rob Stoneman & Rowland Broomfield* | |
| 2= Colin Banks & Wally Brammer | 2- Trevor Jones & Paul Gollins* | |
| 2= Mick Dawkins & John Hall | * Championships decided by Run-off | 3- Clyde Cardy & Taffy Harding |
| 4- Roger Measor & Steve Wheeler | 4- Dick Evans & Kevin Day | |
| 5- Eddie Tucker & Dave Ward | 5- Bob Attwell & Tony Attwell / | |
| 6= Dennis Teasdale & Keith Chapman | 6- Ken Jones & Steve Wheeler | |
| 6= Pete Robson & Dave Hopes |
16 July 1978 at Pinvin
| Unlimited (Championship) | RH Sidecars (Carnival Kings Cup) | 500cc |
| 1- Gerald Short | 1- Steve Smith & Trevor Pye | 1- Clint Ward |
| 2- Clint Ward | 2- Mick Faulkner & Ross Tristrom | 2- Gerald Short |
| 3- Rob Smith | 3- Peter Brown & John Morron | 3- Ross Winwood |
| 350cc | RH Sidecars | 250cc |
| 1- Mark Wadsworth | 1- Peter Brown & John Morron | 1- Mark Wadsworth |
| 2- Rob Smith | 2- Mick Faulkner & Ross Tristrom | 2- Clayton Williams |
| 3- Tig Perry | 3- Roger Reece & Brian Dunn | 3- Mark Nicholson |
| Martin Goddard Trophy | Taylor Transport Shield (R2) | |
| 1- Tim Curnock | 1- Ross Winwood | |
| 2- Ron Radcliffe | 2- S. Balster | |
| 3- Stephen Maile | 3- Brian Evans |