how many should it have or is it good to run
I am not real familiar with the Sachs motors so this may not be totally correct. My opinion is, you are getting on the low side of compression. I would think you should be above 160#. Does the bike kickstart easy or hard? If it kickstarts hard but you can push start it, that is an indication the compression is getting low. I'm sure Doug W. or Ron C. will have an idea of what the compression should be on a new engine and what is acceptable with a used motor.
Rocket
That is too low and I am sure if you check the clearances that will be confirmed. When singles get much below 140 pounds they are starting to go South. 125 pounds and it should be a little hard to kick start and a broken skirt is not far behind.