Sudden problem

Lickity split start with pedals. No start with pull start. Runs fine.
Any help would be very appreciated.
Thanks for reading.
Mybike

Thanks gearnut.
As for no 1, rope does turn engine. (48cc starfire chrome)
as for no 2 i have been wondering about that.
As for no 3 my fingers, hand and arm believe the compression is good.
While i waws eating a corndog i started thinkng this problem started after i filled it with gas this last time. Mixture should be 25:1 synthetic.
I think i'll drain tank get new mixture and see what happens.

Mybike