Two months ago I adopted my standardbred. He was trained as a pacer (never raced), but he trots in the field/under saddle. I’ve spent the last two months getting used to him and getting him more balanced and off the forehand at the trot. This week we tried the canter, and he picked up a decent canter his first time over canter poles, and keeps cantering after the poles 
My issue is, he won’t turn once he is cantering! He keeps cantering full speed into the fence, then stops at the last second… I’ve tried pushing him with my leg, and using and opening reign, but he just keeps going straight. I can practically bend his nose to my foot, and he won’t turn at all. I’m thinking this is just an issue of his balance at the canter, since he is able to turn very well at the walk/trot, but I would love some opinions and tips! Thanks 
How strong are your outside aids? Think about pushing him over, not pulling.
That’s true, I was focusing more on pulling than pushing… Thank you, I’ll try that
[QUOTE=Cookiemadusa;8369398]
That’s true, I was focusing more on pulling than pushing… Thank you, I’ll try that[/QUOTE]
It’s just something to think about. We automatically think to use our inside rein to turn. And yes, the inside rein has its place, and turning is one of them, though I like to visualize it like this: My elbow is the hinge of a door. The door opens, and with my outside aids, I ask my horse to move into that open space.
If you think about where your weight as the rider goes when you’re using too strong of inside aids, your seat and weight will natrually fall to the inside. Horses move away from pressure. So try as you might, you’re actually contradicting yourself through your weight distribution.
Standardbreds are not famous for their quality of canter (I had a 1/2 Stbd years ago and my trainer always said she had a “funky” canter). You need to be lunging him at the canter and working in long-lines to help with the steering. Yes, you can canter a horse in long lines if you know what you are doing. On the lunge, with sidereins, he will have no choice but to turn. Also, try to establish a good, forward trot on a 20m circle, then on the open part of the circle, canter, then back to trot as you approach the wall (fence, whatever). Do this until he’s comfortable cantering the open part of the circle, then begin turning before you get to the fence and ask for the transition back to trot. Eventually, you’ll be able to make the turn without a transition and he’ll feel more balanced. As BrownHorse said you need good outside aids. Push him around the turn, don’t pull him around. It’s about his balance, as you surmised.
H should already understand turning because of the work you (should) be doing on the longe. Also, you should be working on bend and circles, serpentines and figure eights at the walk, at the trot, and bend on the longe with side reins. Your ground work teaches him to yield to your leg (whip laid against him or tap tapping his side with you on the ground at his shoulder) and lateral work. All this LONG before he even begins canter under saddle.
What you horse told you were the holes in his education. He does not understand outside rein and outside leg on a bend; he is not balanced enough to be cantering, and his shoulder is not flexible nor strong.
The horse is not yeilding from seat and legs, nor relying on the outside rein for suport. He is not flexed at the jaw, nor at the poll, and is rigid. That rigidity is apparent because he cannot bend or yield at the canter.
Ground work, longeing and bending under saddle - he should be a gumby at the walk and trot, whilst keeping his shoulder upright and bending around your inside leg, jaw to poll to tail.
Start again.
