I recently bought a 2008 rmz 450 unknown hours, got it home and was really hard to start but seemed to run okay when it was started. Drove it a couple times then couldn’t get it to start at all. Checked timing and noticed it cams weren’t lining up when on tdc. Ended up replacing piston for preventative maintenance and put a new timing chain and set valves (they were tight). After this i still cant get it to start and after about 15 kicks it will backfire. Tried to jump start it and kick it but no luck. Wont even attempt to run. Any help is greatly appreciated