Motorcycle Safety & Driveability: correct tire pressure of motorcycle, Tyres, tyre size

Question
good day!i have a bike with 135cc and the original size of tire before is 90/80/17 front and 100/90/17 rear but now ive change it to 100/70/17 front and 120/70/17 rear..how many psi do i have to load in my tire sir..kindly help me please sir?thanks

Answer
First of all, you should never change the size of a tyre profile without checking with the bike maker first that it is safe to do so. The narrower profile may slip from the rim and a larger profile can cause a flatter profile making cornering unstable.
The tyre pressures should be the same but you MUST   check with the bike manufacturer that it is safe to change to the size you have chosen.