Sailor can you post a picture of what is eating your lunch? Is it the nut holding on the mag/rotor and in your case the I 'm guessing the starter cup I'm wondering if the nut is stripped?! in that case send it back if its new.
thank you very much for this info and i remember the guy that used to tune my old racing bike always surprised me with a little gift which was a new part from japan so sounds like they are still ruling with parts... will look into the 'tas spitz', and from the sounds of things i just may need to get some help from a tinkering man so when i get an engine i will send whoever decides to help me here to speak with all of you - that way none of you will have to go through explaining the abc's to me at least 2-3-4x >> if not more lolThe 65-70-"80" cc engine kits (there are no real 80cc engines, they are all 67.5cc's) are all ABOUT the same...made in China, dubious quality control but lots of fun if you are into tinkering with stuff. The rack mounts I can't help much with other than to say look for one's with Japanese engines like Honda for starters. You do have to watch for things like "Honda designed"- which is a crock, or weird/no name brands on the engines.
Right now I am running a rack mount, which is 28 years old with NO PROBLEMS, other than it's pretty slow- 22 mph tops speed. It's called a TAS Spitz, they were also sold under the names Free Spirit (Sears) and Bike Bug.
The engines do all come "put together", except for mounting them on the bike, but the directions for the frame mount kits are good only for the bottom of the bird cage....that where we come in...the best directions are right here on this site.
Start here- http://motorbicycling.com/f30/bicycle-motor-preperation-care-354.html