Basically - drill small hose/s at extent of crack. Remove paint on inner/ rough up key surface (1" - 2" either side). Use making tape on outer face of fairing crack to hold together - Use a soldering iron and cable ties to melt/work out crack. Use P40 to make a thin layer - lay in fine aluminium mesh, and lay more p40 over to strengthen.

Now work can begin on outer fairing use dremel to cut a V into crack , use soldering iron again to melt /work out crack. Then fill with plastic bumper filler. Wet Sand flat with progressively finer wetNdry, fill any odd pit. rinse and repeat. spray some grey plastic primer and /or plastic filler, wet sand till everything smooth. Spray primer again and gently smooth with wet 1200 to key for final coat. Find your colour code on subframe under seat. 3 or 4 coats - allow to dry light sand with 1200 to remover any orange peeling - then finish with ProXL utra Gloss Lacquer. Viola

What did you use to repair your fairings? How long ago did you do it? Is it still holding and not cracking?