Hi i'm new to the forums so I hope im doing this right but I can not for the life of me shim my v2 gearbox right. I tried shimming so none of the flat surfaces of the gears touch but theirs still optimal gear mesh. The gears sound fine when i spin them with the gearbox closed up and a few screws in but when I put it all together and fire it, it makes a loud screeching sound when it fires. I have tried adjusting the motor height it doesn't seem to be making much of a difference in reducing this sound. Any tips on if a loud screeching sound means it is just shimmed to tight or if my gears just don't like my gearbox? I am currently running 13:1 SHS high speed gears with an ASG ultimate motor and 11.1v lipo. Thanks for any help.