PTS Masada upgrade questions

[Red Dot]

Hello gents!

So I've rolled up my sleeves a bit and dived into some of the internals in my PTS Masada SV. I added a ball-bearing spring guide and today had the guys at Pinnacle Hobby in Markham (awesome store and great people fyi) install a SHS high speed motor. I picked up a Venom 11.1v 30c 1500mah lipo as well to try out. Now to my questions.

1. How do you tell a motor is properly seated with the gearbox?

2. I was double firing on semi with the Venom battery but not with my 7.4v lipo, got a M90 installed. Too much power in general with an 11.1v or just for that spring?

3. The motor was getting quite warm with a couple of short full-auto bursts, when do you worry about it becoming too hot?

Thanks guys!

[lurkingknight]

1. when it doesn't sound like a screaming banshee.

2. more than likely you are overspinning, too much motor and battery for the spring so the gears are still spinning after a cycle. Weaker motor or lower voltage battery or stiffer spring will solve overspin. If you do a stiffer spring, obviously your fps comes up. To bring fps back down you need to short stroke the sector gear and piston, which would need a piston with at least a half steel rack. Minimum spring for most neo motors to stop overspin is a 110 spring. A 120 would definitely stop overspinn. -3 teeth will bring a 120 spring back down to 350ish fps. If you can't handle short stroking, probably best to see a gun tech that knows how to do it. (stealth, gbbr, a few others)

3. SHS motors run hot and draw a lot of amps (compared to other neo magnet motors. All neo magnet motors draw more amps than standard ferrous motors). Some techs recommend more mah and C rating if you run shs motors. Realistically find the biggest battery with highest C and mah you can stuff into your battery compartment. If the motor tries to draw too much power, it can over draw your battery back which can cause damage to your lipos, and potentially cause a fire.

[Red Dot]

Nice! Very helpful!

I won't be getting into short stroking so I'll run a 7.4v for now however I am concerned now that I might smoke my 7.4v lipos with this motor. One is 1200mah 15C and the other similar at 1100mah 15C. Could issues arise?

[lurkingknight]

that's pretty low..

1200mah 15C
18 amps


1100mah 15C
16.5 amps


SHS motors are higher draw... I have 3 lonex motors in 3 different guns drawing 22-25 amps.
I've seen ferrous motors in stock guns draw anywhere from 13-18 amps, average being 15.

I would say even if you're perfectly shimmed, you're on the borderline of overdrawing the battery. Buffer tube lipos are pretty crappy.

You might be a bit safer because you have a stock ratio gearset and a 90 spring.

[Red Dot]

Sounds good, I might need to find some beefer 7.4v. I got another 11.1v on the way that I'll try with the M110 and M120 I have en route.