I have to agree with scoob here.
I think that the advise Dan gave you is quite correct, but only if your bike has the umph to do it. I think with that ttr125 you are going to have to rely more on momentum than brute power off the jump face. Even if you are on the throttle at the release, you better have enough momentum on that little bike or you will continue to come up short. Your arc and positioning may well be fine, but you need alot of run to make a bike that isn't really a jumper, jump correctly(or as far as you need it to). I realise that there have been a few here that think the ttr125 is the bike from heaven, but <coff> I think you would be better off with another bike if you are jumping. You may be fine with that bike, but if I were you...I'd keep pulling back on the bars until I was sure the bike was making the crest of the next hill. A correct postion and arc are bad things when landing short on a double. (ouch) the word "T-bone" comes to mind. :p