I'm going to guess that you ride at a very slow cadence and are using your upper body to help push the pedals. I'm going to guess that your right side is dominant (ie, that you are right handed). You are also favoring the left knee. These may all combine to create your right-leaning tendancies.
Originally Posted by
daven1986
I have tried loads of things, but it keeps happening.
What things?
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You aren't really providing enough details.
You'd probably be better off asking somebody who can actually see what you are doing.