urgent help please!!

[Chrislong]

Check the engine for pinch. If the engine is a cheapish one, or the one that came with it as an RTR, from new you should be able to just turn the flywheel beyond the pinch - with effort. More expensie/competition engines will tighten up and lock, won't be able to from new.

But if you can turn it past pinch relatively easy, then it doesn't need to be run in. If its an expensive/competition engine and you can turn it past pinch with some effort, it doesn't need to be run in.... it'll have done a fair few tanks already.

Incidentally, if it is tight, after running it make sure the flywheel is turned so it can rock - makes it easier to start next time, and its easier to do this before the engine cools otherwise you may need to do it with a screwdriver.