I have a 13.2hh welsh section c, his tack fits correctly,and isn't irritating him and he behaves really well when he's in the school. When I take him out on the road, he rams up the backside of the horse in front, and races them too. If he's not doing that, he does this instead (and he does this hacking out alone too) Trots as fast as possible, and won't maintain a steady pace. When given the correct aids, he merely puts his head up higher, gets the bit in between his teeth and starts over. If I manage to get his head on the bit -and then I loosen the reins as a reward- he prances along, jog trots and sticks his bum out into the traffic. What can I do?

It sounds like your pony needs to learn what is expected of him on a ride. To begin with you should try and work him first in the school so that he is tired and not as fresh. Then, afterwards take him for a short walk. Try and make this relaxing and only go a short distance. Do this every ride until he learns that nothing exciting is going to happen and he only needs to walk. Keep him at a walk until he is relaxed walking. Even if you only walk to the end of the driveway and back keep doing this until he behaves well. You can gradually increase the distance as he starts to behave better. This may take some time. Please try and hack him in the fields rather than on the road. Keep him at a walk and as you are walking ask him to bend and do different things. You can make small circles or halt and make him stand for a minute. Vary the routine so that he does not know what to expect. If you can have another horse with you it is better. Horses are happier in groups.If he tries to get to close to the horse in front ask him for a half halt so he slows down a bit and keep asking every time he gets to close. Arrange with the other rider that all you are going to do is walk. When you are able to take him out and have him behave then you can try riding on the roads again. As before though keep it at a walk until he learns that he still needs to do as he is asked when on a ride out of the ring.