Hi sifoo sifoo sekalian

would like to understand a little regarding riding position ergonomics

I was riding an Xadv 750 and after 2 hours in, my right shoulder (the muscle between neck and shoulder) started to have a numbing pain

it stopped when i stoped to rest and came back when i starter riding again. i summarize that this has to do with the riding positon


question

1) How do i know that my riding position is correct? (eg. cyclist will have a few pointers for fitting but i cant find any for motorcycle)
2) is there any place in malaysia that does motorbike fitting to reduce this pain