1983 Yamaha tri moto 125 will not pull start but will pop start?

I had the same issue after a complete rebuild and replacement of numerous parts. One of the previous owners incorrectly wound the recoil pull starter rope in the wrong direction (when facing the internals - counterclockwise) and also put the pawl (metal thing that pops up and engages the shaft pulley wheel) in the incorrect slot (rightside hole). I read a blog of the same issue. I wrapped the cord in the correct direction i.e. clockwise and put the pawl in the correct slot i.e. the left side hole (the pawl was metal stamped with a big "L" by the way), installed the whole assembly back on my Tri-Moto 125 and it now starts on the first pull everytime; no more push starting! I hope this is the issue you are unfortunately facing and now it gets fixed...good luck.