so...just to elaborate...where you planning on riding this motorbike, and why shouldnt it have pedals?
for a budget of $150.... keep walking, or catch the bus.
you gunna have to get it registered if it has no pedals. its a MOTORBIKE. you can take that rule to be pretty standard across several countries let alone states.
which means it has to have very good brakes, front and back. they have to pass DOT or ADR or similar design rules for motor vehicles.
unless your from some parts of south america, asia, or other "third world" countries?
your link is to a push button switch, no more, no less. you could hook it up to your bedside lamp. use it as a kill switch. use it as a starter button. stick it on your shirt with "hit the button" written over it...
but then youre going to spend a few hundred on somehow installing a custom electric starter and battery, and wiring, up to your less than $150 engine... custm machined parts dont come cheap.
a pullstart is fine, except when the string breaks...great. now you have no pedals or a way to start the engine. enjoy the push home
to put it all in a nutshell... you want the impossible. a $150 motorbike...
sometimes you have to be cruel to be kind...it isnt going to happen! stop dreaming! add another zero to your budget!