Little studs can be a pain in the @$$. They are more prone to selling up to your leg than other horses. You have to be more insistent to get your point across. They take a lot better timing and feel than other horses. That is why they are harder. Even Bob Avila charges $100 bucks more a month for little studs.

I'm not saying get in a fight and try to force your point across, just get smarter. To compensate for your little legs, get some good timing and some good heavy split reins, or a crop. Timing being the important part of it. Ask nicely, then wallop him, get your point across swiftly and surely, with good timing.

A lot of people would go to the muscle, trying to pull harder on the nose to force a turn. Then they start pecking with their legs, while their body gets stiff on the muscle. A downward spiral.

Instead, tip his nose, kiss or cluck to him, add a bit of outside leg and give him a chance to follow his nose, then go for a spank. A crop, or an over and under with the reins, I have found to be the best way to get a little stud's attention. Over spurring them makes them sull up more and become a tight little ball of muscle. The crop or the over and under will reinforce free forward motion. Most likely that is the problem; he is sucking back behind your leg and losing momentum. Getting it back would be the first step towards getting the steering. I hope this makes sense! Good luck.