I use to do a lot of weight training for about 2 years but i recently stopped it as it was messing with trials.
Before i started weight training which was feb 2011 i weighed in at 15.7 stone and i am just around 6ft. I then went down to 14.2 stone and i now currently weigh 14.9 i would love to maybe get down to 14 if i could.
I am now focussing on my fitness for comps this year i don't fancy getting any bigger or gaining more weight.
Aswell as riding trials maybe consider getting a xc or road bike? Its made a difference to me recently as i do about 20-30 miles a week on me xc bike so my fitness has progressed.
Drink water and lots of it.
Eat brown bread not white.
Try and at least keep on your 5 a day of fruit and veg.
Fish, chicken etc.
Rice, pasta, oats..
Its what i normally eat/drink although every weekend i like to have the intake of junk food for one meal lol.