what is a motor plate shim?

[CCCman]

i was looking around and saw these. what are they and what do they do?
http://www.airsoftpost.com/product_info ... s_id=30565

[Jewish Ninja]

They go between the grip end plate (AKA heat sink) and hold the motor in the correct position. There is no real reason to buy an aftermarket one unless you lose one.

[Nec]

What JN said.

Those particular ones you linked to are supposed to be larger than the normal "disc" type to help with short motor adjustment screws, allowing the motor to go in farther to engage the bevel gear better. I’ve found shimming the bevel gear lower is more effective than installing an enlarged disc.

[CCCman]

my classic army scar didn't come with one, it just has a very wide screw at the bottom that goes up and down

[BlacksunshineGAAS]

If you have the large screw then you likely don't need one at all. My team mates KWA was locking up so I removed his shim plate and that alleviated much pressure and allowed for better function. Sometimes you need them sometimes you don't.