Building your own ULTRA4, Stock Modified, Stock,  Legends, or UTV? Find out all the rules before you start your build. All safety rules must be followed by all classes.

Download the ULTRA4 Europe Rule Book. – Updated 5/2017 – updates are highlighted in RED. Table of Contents is Clickable. 

Pro Comp Stock – 4600 - 8.3

Rubicon Expess Modified – 4500 - 8.4

G2 Wheels Legends – 4800 - 8.4.11

UTV Class - 4900- 8.6

4900 - UTV Drivers: Classes have been simplified to one class.  Please consult the ULTRA4 Rulebook section 8.6 for KOH UTV rules for KOH UTV Race.

Ultra4 Chassis & Tech Sheet can be viewed here.

Should you have specific technical questions, you must cite the section of the rule book to which your question pertains and email our tech inspector at

Maxxis King of Britain
Kirton, UK

2/10/2017 Driver Update - Click here for 2017 King of Britain Driver Packet

We are excited to announce that the site for this year’s KOB has changed to Kirton Off Road Centre.  It is never our desire to change a venue once the schedule is set, however, due to unforeseen circumstances our booking with Bovington was unexpectedly cancelled by the site. Kirton is the original location for the short-course Rampage races held on a small portion of the terrain available for competition. We plan to use the entire site at Kirton to build a course worthy of the ULTRA4 Europe finale. The Euro Trial recently took place at Kirton and provides a fitting example of the technical terrain available at this location.  Chris Bowler has already begun working his magic on a brilliant course and rest assured, there will be rocks.

We had booked our 2017 dates with Bovington shortly after the successful 2016 event. However, Bovington recently was forced to cancel the booking due to unexpected military training exercises scheduled for that same weekend.

The date of the event has not changed, and Kirton offers ideal ULTRA4 terrain in a location where fuel, food and restaurants are all within 5 minutes of the site.

Address: Kirton Off Road Centre, Gainsthorpe Rd E, Hibaldstow, Gainsborough DN21 4JL
Host Hotel: Forest Pines, Ermine St, Broughton, Brigg DN20 0AQ. Tel: +44 (0)1652 650770 Quote Ultra4 Europe to get discounted rate.

During the event there will be a food tent and bar on site.

For travel planning purposes use postcode DN21 4JL.