Low firerate on a TM AUG - dying motor?

[ancorp]

Have an AUG that was laying in a box for a while because it never performed too good. When I got it it fired only 220fps with .2s.

Completely stock inside. Internals look minty, but the spring is clearly too soft. Stock TM spring with the hook that attaches to piston.

To make sure the spring was the problem, I replaced it with a stock Cyma AK spring that fired 290fps.

Fires 300, all good. But the fire rate is low. It was kinda low with the 220 spring also. Wiring is perfect, battery top notch. Everything seems 100%. The gearbox sounds smooth, shimming and motor height don't look like they could be a problem. I'm guessing it has seen a lot of rounds, thus a weakened spring, and perhaps a completely worn motor?

I don't know that much about motor life, but I assume they slowly lose efficiency/RPM and then just die.

I'd swap the motor with an ICS 3000 to do a quick test, but the AUG motor is soldered on, and I'd hate to take it out and find out it's not the problem.

Anyone have similar experiences and solutions? Could be anything but the motor?

Thanks!
Alex

[Styrak]

I'm no expert, but I have an AUG too. Sounds like it might be the motor. What kind/size of battery you using?

Oh also, maybe make an audio recording of the fire rate and I could compare :P

[ancorp]

I tried a 8.4 1400mah Intellect Mini, and a 9.6v 2000mah AK stick. I'll measure the RPM eventually.

[Skladfin]

really? if its shooting atleast 10rpm then its quite acceptable

if you shimmed it too tight, it will lower you RPM quite a bit, could even make it stop shooting.

If motor isn't the problem, then take out all shims and try again.

[ancorp]

Well Ill be damned.

Upon reassembly and dryfire with that same 8.4, the firerate is now quite good. I'm thinking 13-16RPM.

So err... close thread?

Weird.

[Styrak]

Good...job then?
Lol.

[tycho]

Um...when you say RPM do you mean RPS?

16 rounds per minute is...well...bad.

Bring that puppy out to defcon and we'll see whose shoots better >