new motor question

Just to give a little backstory, I had two previous kits (49 and a 66cc) and this was my first time mounting a kit to a suspension bike. I had purchased an 80cc /100cc engine with a high compression head. After mounting the engine and setting up the whole bike, I was relieved to see that my...

Ok so I have ruined 2 engines already. The first one I bought with the kit off ebay from BGF and it was a total turd. Lasted bout 2 hours before throwing bearings under the clutch and never running again. The second one I was truly happy with and got that one from dax. Ruined that one due to...