New to this site so Hey everyone.. Iv have made a mistake I bought a second hand wk sport 125.. Its a 65 plate and don't just over 8500 miles.. After riding around for couple of weeks the engine developed a rattle so checked oil and all good.. Took clutch basket off and replaced the lot.. And still sounded like a bag of nails so I bought another 125 engine to go in... Not the same as what's in the bike but has same connector exhaust mounts the same and carb etc New engine is spot on with low miles and I new the bike so I no its all good.. Fitted it in my bike everything switched on and started fine.. Went for a ride and during that ride I has to stop at a couple of shops so the bike was turned off and started 3 times with no issues.. Then it wouldn't start at all.. After a push home.. I went thru all the connectors.. Checked for good spark.. Checked for fuel issues.. Cleaned the carb right out and checked the clutch safety switch..and still nothing.. Anybody have any ideas please