I am the proud leaser or a 17.2 Dutch Warmblood gelding. Being 5’1" on a good day can make things interesting. I normally jump him in a Pelham with double reins and try my best to flat him in a slow twisted D ring. He is not very strong at all, most of the time very lazy. It’s just when we start doing lead changes and more advanced stuff he takes his job very seriously, little me can barely hang on! He has loads of impulsion and a not so sensitive mouth. He goes perfect in a Pelham but that isn’t a bit I would like to use for everyday flatwork. Any ideas for a bit for him? Thanks!
Have you asked the person you are leasing him from what they would do?
That would be my first clue.
Opinions that may be very wrong, but what my gut feeling is saying from your post:
1.) sore hocks. just basing this off of your lead change comment. Strong or sticky changes often means hocks are sore. He may also just get excited about lead changes, but it’s worth having checked out. Does owner have rads or anything you could have a vet look at?
2.) Being a bit… well, short, can have disadvantages, especially on a big horse. If he gets strong when asked to do serious work, my answer would be to sit down a bit, put some leg on, half halt a lot and get him collected. But if you can’t wrap your leg around the horse, that makes it difficult.
3.) If the pelham works, it may be the leverage it is allowing you. Do you not want to use the pelham because it has leverage or because you see it as being harsh? You can always get one of those rubber or happy mouth double jointed pelhams if you want a bit softer pelham.
Are you working with an instructor? You need to ride him more from your seat and core than from your hand. This has little or nothing to do with your size, and tons to do with how you use your body.
I dealt with the very strong horse all year (my trainer liked to call him a freight train)
Working in the indoor was difficult for us as he was still building the strength to carry his body. If you make sure this isn’t a pain thing, and speak to his owners there are other options you can try.
It’s all well and good to say that the rider has to change their position, or the horse needs to listen, but you need to get to that point safely. Which is why we went to a dutch gag (3 ring French link elevator) for a month. It gave me the feeling that I could really sit back and ride, and work on my position and his fitness, without compromising safety. A month of that, he went back outside and he is now in a thin mouthed French link loose rein. For over fences he is now going in a full cheek slow twist. My position and strength, as well as his, benefited greatly from that little bit of extra whoa I got from the bit.
Now if he starts rooting, or gets stupid strong over fences in a lesson, the next day I pop the bigger bit in as a reminder to sit back and listen. He is then perfect for another month or so.
The trainer who rode him for me a couple times put him in draw reins for that same reason. It gave her a bit of control so she could work on other things not just fighting his freight trainness.
I agree that a lot could have to do with your body and position and leverage. That being said you shouldn’t have to fight him your entire ride. I spent 3 years finding a bit that would work. My horse has had a hard mouth since 3. In a simple D he just locks his jaw and pushes through me. Anything stronger and his whole body gets stiff and fast and fights. I finally found a bit that lets me lift him, gives total control, and relaxes him. Now our rides are actually productive instead of a constant battle of half halts. https://www.smartpakequine.com/pt/neue-schule-verbindend-loose-ring--16mm-12140?utm_source=cpc&utm_medium=google&utm_content=shopping&utm_campaign=nb_shopping_tes&utm_term=22140
This may be an inappropriate suggestion for your discipline, but the real Buck was much like you describe. Though size-wise we were a good match, and he was easy and pleasant on easy work - he would get very focused and exuberant as the work became more challenging and would freight train. He just found new challenges exciting. But I would feel out of control and ride defensively, he would get defensive back, and the quality would deteriorate. Switching up and going bitless once in a while actually helped the most.
Perhaps look into a kineton noseband?