Every Magnum I have had is VERY tight at top dead center when new. Read the manual, follow the break in instructions and you will end up with a good running motor.

Try pre heating the engine with a heat gun or hair dryer.

I use the Thunder Bolts from Hobby People or Enya #3.

Is this a .52 two stroke or the .52 four stroke? The 2s has a finiky mid range. Takes a while to get it tuned but the engine has tons of power.

Buzz.