My horse raises his head when i ride him Why is that and is it to avoid the bit

i don't want to use a martingale of any kind, is there anything that might help though?

First you need to rule out any physical problems the horse may be having such as wolf teeth. Best to have a vet check his mouth. If nothing is wrong with the horse then you need to check your equipment. Check your bit for rough spots or nicks etc. Think in terms of how a piece of popcorn can irritate your own mouth, thats how sensitive a horses mouth is as well. Look where the bit rotates on the cheekpiece...is it pinching his gums there? Check the headstall.again.he is sensitive so look for even small things. Put one oat grain in your shoe and walk on it..thats how sensitive your horse is as well. If you have access to an experienced horse person ask them to assist you checking your equipment. If all this checks out, you can start to look at YOU and how you use your equipment. Are your hands quiet when you ride ? Are you constantly bumping your horses mouth with your hands ? He will learn to avoid pain caused this way by raising his head. Again, it is obvious you are learning so if you have access to an experienced horse person now would be a good time to ask some advice. Have them watch you ride your horse at a walk around an arena or small paddock. Then maybe a trot and lope but only if your horse is NOT exhibiting the head raising problem. If you have a video camera you could also video tape a couple of your rides and ask an experienced horse person to review it. If you can rule all this out then you may have a training problem and it is time to go back to the round pen and go through all the basics again until you find his weak spot. People write entire books on round pen training so there is no way to cover all that in here. Suffice to say you will need experienced help at this point. I do admire you for resisting using a martingale, that is not a proper cure for a problem. You do need to fix this problem as a horse that raises his head is NOT under control and this can lead to a wreck.