I'm the same, i just can't seem to get far enough back. Although i do find that instead of trying to get your hips back try and lift the bars and kick forward with your legs. (Drop your heel).
Thanks for the input chaps. Comforting to know I'm not the only one. I've watched all the tutorial videos on Youtube, and I'm confident I know what I'm supposed to be doing. It's just another thing actually doing it. I think you're right I need to get further back and lower, though.
Best advice I ever got about manualing was to not pull up on the bars, but to push your hips back while pushing the bike forward with your arms and legs. Almost like your trying to push yourself off the back of the bike but still hanging on to the bars.
Try to really exaggerate the movement so that you loop out and then dial it back from there to find your balance point. It will be easier if you can find a bmx bike or hardtail to practice on.
Try to stay out of your head, and just keep trying; it will eventually click. Trying to describe how to balance a manual is like trying to describe how to ride a bike or weld.
You just have to keep trying until you get a "feel" for it.
Thanks with more practice, at faster speeds I can now raise it high enough but can't hold it, low speeds not so much. Can drop off road kerbs more often than not.
Mind you I'm like nearly 40 lol
Also, i discovered "moving hips" to be inaccurate, I had to kick the bike forwards to raise the front.
In my view, your problem is you don't know where the tipping point is.
A manual is a balancing act. You have a pivot point, behind this pivot point the bike flips backwards, in front of this pivot the bike returns to it's rolling position.
This might sound crazy but find a nice soft patch of well-kept grass, some soft dirt, sand, or any similar surface and practice intentionally flipping yourself off the bike. The goal is to land with your feet underneath you, and the handlebars still firmly in your grasp. It can be done quite gracefully and safely but the soft ground is precautionary. I recommend doing it at low speed, there is no such thing as too slow as long as starting manual itself doesn't have the ability to impact your speed. You could practice nearly at a standstill. If you want, to start, hold your rear break down and practice rolling over backwards while sitting stationary to get a feel for how you will catch yourself.
Once you've found the edge and you can reliably tip your bike over, usually hopping off and catching yourself with your feet, you'll know what you are aiming for and the practice of flipping yourself over will give you more confidence to pull harder because you know if you roll over you'll be fine.
Once you can tip yourself over rapidly, try to slow down the process. Instead of tipping over in 0.1 sec, try to make it take 0.2, then 0.3, but still always tipping over. You will be able to feel the shift and get a sense for the balance of your bike on its rear wheel.
The next step after that will be to stand up and correct for the rollover just as you are approaching that "edge", then holding it! Easier said that done, but you will be closer!
When I was a kid doing manuals, half the time you fail a manual you return to riding, and the other half you hop off the back of the bike to your feet. So if only one is happening, you aren't close enough to the edge and a manual is by definition finding the edge.
I'd suggest like the others, to drop the seat right down to the min to allow you to get your hips lower without worrying about hitting your nads when your moving back.
Also just practice leaning as far back over the rear wheel as you can with your arms outstretched without actually pulling up so you just ride normally just with your whole body as far back and as low as possible to get used to the position.
Once your happy rather than yank up, rock back fast to that position and your outstretched arms should pull naturally on the bars without using your arm muscles. Keep doing it faster and harder till you come off the back or snatch the rear break to come crashing back down. Somewhere between there and where you are now is the balance point and you'll have to find that on your own bike but keep practising!
I find it better to keep going too far back than not enough when learning cause you can lightly use the brake to bring the bike forward again and then lean back again and its basically a juggling act between these too techniques!