Center Of Balance

[QH Jumper/Luver]

I have been jumping for a few years, and 2' 6", but have only started to get more advanced with different horses and commands. Lately, I have been riding this unpredictable horse *whom I loved and helped train English*.
His name is Mister and he is a pure Quarterhorse. Now, when I enter a jump, he may go as slow as a snail, or as fast as a cheetah. In the same day.
Sometimes this throws me off with whether I should slow him or speed him up, and I mess up jumping. (In the middle of a 1'stride when I have hardly any time). I might give too late, or rise to early and lose control.
Recently, I didn't have time to rise into the second jump of a 1'stride. Well, he jumped BIG and I felt like a rocket that was launched!! I barely stayed on.
Could I have some tips for this?

[Piaffe]

Several questions here:

1. How old is the horse
2. How experienced/not is he?
3. Have you tried freeschooling him over jumps to see how he goes without a rider?
4. Have you seen him jump with anyone else?
5. I am assuming his tack all fits correctly and that he isn't in any pain?

sorry for the questions - it's difficult to comment on your horse's reaction with some info!!

[kedwards]

It sounds like you've been riding longer than me, so I don't know if this will be any help. But whenever I (and the horse I'm riding) am having difficulties with striding or maintaining a steady pace, my instructor has us do ground poles and grids.