Multiple questions of things that confuse me

Hey everyone, I am sorry to put this all into one box but for me, it would just mean I do not chase all over the forums writing many questions. I will put them in numerical order so that you can answer them if you know, according to the question number, OK.

  1. Gearboxes, what is the differences between Gen 8, Gen 9, Gen 10 and V2 etc?

  2. Which ones are compatible with which in question (1)?

  3. My current gearbox is standard at 18-1 and is a full nylon system if I was to change it for 16-1, would I need to change the pinion gear?

  4. Springs, I understand the 1.10 1.20 as it relates to the diameter of the wire or gauge if you like. Where and how do M90, M100 etc relate to this?

  5. What is the point of an unequal spring?

  6. Is the gel ball driven out by spring force or air pressure? I ask this because it seems a rather complex means of getting the system to work, so I just want to understand the basic operation.

  7. Lastly, this is more of a mathematical conundrum. If we have increased the ROF by means of a battery, motor, springs and gears, the feed motor in the magazine will still only provide a set amount of gels or will it spin paster and if so, why?

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Gen 8, 9 etc gearbox is mainly a physical difference. they all behave in the same way, they just fit/mount differently.
if you go 16:1 it will most likely be metal gears in which case you will have to change the pinion to metal too. (plus anything else the gears touch, reverse latch rail etc. if its still nylon the pinion is fine
M springs are measured in metres per second rather than thickness i have a M150 which is about 1.6mm when measured if that helps.
unequal springs take stress off of the gears so i recommend those where possible
i’ll post a gif i found that should help with question 6


how they all work


Hi Spartan 19. Firstly i am not an expert there are alot more experienced people on the website then me

Basically most gearboxes same the same basic mechanical system to fire the gels, and the newer the gear box the more refined the system has become. This doesnt mean that the Gen 8 is bad, the older systems can be modified and tuned to be comparable to the newer Generations of gear boxes. Me personally am using only gen 8 blasters as they are cross compatible and parts can be interchanged. To play it safe stick to parts from the same generation/gearbox type and you should be safe. Some parts look the same and may not be compatible which can be problematic.

Be careful with changing gear ratios, if you dont have experience or know some one that does it can cause you problems doing it blind (i know). best to stick to stock and gears for now. Get a spare gear box and test with that so if you screw up your not down a full blaster!

The mag motor will also increase its feed rate with the 11.1 v battery (compared to 7.4v) just the same as the main motor although if you use some of the extreme motors (High speed) the standard mag motor wont keep up and you will have to upgrade the mag motor as well.


Thank you for the explanations of 1), 3) 4), 5) and 6). The Gif certainly does a lot in the way of explaining the mechanics of the operation. :dizzy_face: :tired_face:
I have listened to builds that the spring pressure was greater than the motor or gear ratio and they just stopped working. Fortunately, the builders were smart to test before complete assembly, however, none of them mentioned the unequal spring option and either dropped a spring thickness each time until it worked or just put in the original.
So, that again leads to the question I asked in number 6). as I see it, your answer gives a partial explanation, that is the gear relief but is the other half providing any real benefit?
You say you have an M150 at 1.6mm gauge, is it of unequal length? if so, what MPS/FPS are you achieving? Could this same MPS/FPS be achieved with possible a 1.10/1.15/1/20mm spring? Would these not achieve the same gearbox relief or more, dependant on which one actually achieves the same velocity?

Don’t get me wrong, I am not saying your build is faulty or incorrect, I am just trying to figure out these ideas, the advantages and disadvantages. At some point the two types of spring must balance out in terms of pressure applied to the gearbox, I just want to know what that is and then what the FPS difference would be?
It’s the 45 year old mechanical engineer apprentice in me at work LoL

The M150 i use which is a theoretical output of 150 metres per second which is just under 490fps.
In reality its less in real life as thats just the springs ability to return back, friction, piston head weight all of that comes into effect, although i did get a chrono reading of 485 with that spring which is not far from 150 mps.
The 1.6 spring is an unequal and you certainly cant get more fps than the spring can push, so no, a 1.1/1.15 etc could not achieve the same power of a 1.6 regardless if either are un-equal or not. With the M150 i doubt its taking much strain of the gears anyway as no one not even i would recommend using a 1.5mm spring or higher in a practical build. I just do because i’m experimenting with stupid concepts. The speed of the gel comes directly from the piston head pushing back and a puff of air propels the gel. Pressure does not get built up in a chamber and released sequentially after the piston head hits the end.

i hope this helps a bit,



Thanks, Terry, I think the gearbox job will be a way off yet, but I did see some 16-1 gears and I thought they were nylon, so I was curious. I can understand the increase in b attery power will increase overall the gearbox and magazine motor. I too have an 11.1v and on single fire I always get a double-tap output. Nice if you want it, annoying if you don’t. looking at some of the mods I have seen done, motors that spin way faster, gearing down to 12-1, the RoF would get pretty fast. Yet, I have never heard of anyone improving their magazine feed motors. I recently watched some high RoF tests being done and it was noticeable that the gels seemed to come out in clusters of gels then nothing then clusters again. It was so fast that I played the video at 1/4 speed to see the gels it was noticeable. This is what I believe is the magazine,motors inability to keep up with the rest of the blaster. There again, I could be totally wrong too… :rofl:

It is becoming a little clearer now, thanks. My blaster uses a 1.0mm spring and I will probably just take it up to 1.15 or 1.20mm for the reasons you have mentioned. Not wanting to overload the gearbox. I have alreaday gone from a 50% to a 100% cylinder with some upgrades in the internal works as well. This being necessary due to the overal barrel length…The good thing is the spring is somethig I can mess about with quite easily, so maybe I will think about how it performs on stock power at the maximum spring I am going to use. Then if problems arise, I can look at unequal as an option possibly…
my main goal is to get up to 300fps or +30 odd, with a solid hit at 25 mtr and some accuracy. I know it sounds like a pipe dream, but now I have seen it done at 400+ out to 50 mtr, it is just a matter of tuning.

yeh mate sounds awesome, i wish you luck and fun with your journey. the 1.18 spring seems to be the most popular as a well seal rig with good components should hit 300 fps no prob. My m4 is about 280 and is pretty accurate although i mainly test at 10m due to a small backyard. My P90 is where all my dumb ideas go into for fun and i’m certain it always 1% from blowing up everyday. Never under estimate hop ups for range and accuracy either.


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How do i get the motor to shake like that , mine just stays still…


the magic of animation


loosen a few screwws maybe, or just the big tensioner at the bottom too :rofl:

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Onto it haha :laughing:

Nope, back again…Bloody plungers, piston heads and cylinder heads with nozzles now…
Solved the gearbox and spring issues, even put bearings in, instead of the bushes. Then I started playing with the Stock Plunger Assy and Head Assy in the new 100% cyl with stretched green O rings. Sometimes yes, pressure…Most times no, pressure.
So now I do the online shopping trick once more and we are back to seeing the same old story, plungers, pistons, heads for Gen 8,9,10, ACR and SLR with nozzles is just guesswork. When I did find something that said for V2, no bloody nozzle and the people did not know what to use on the parts.
So, over to you guys for that much needed, logic and advice that the shops lack. I have asked M4a1, no reply…Comand Elite, cannot tell me what nozzle to use, X-Force Tac, No reply and BigBoss tactical, No Reply. This is all one week old now with at least one follow up to each one except Command elite.
All I need to know is what I can use in a, 14T V2 Cylinder. Cheers, Jeff

Are you wanting a cylinder head and nozzle ?
What blaster and gearbox are they for ?

Hey Rattler, It’s a V2 in my CYMA blaster. I’m looking to change out the plunger and piston head, as well as the cylinder head and nozzle. So, yes to your first question and but wait there’s more…
The images all look the same for the most part and some are advertised as fitting all versions, while others do not say to much.

if it has the orange gearbox this is a teardown video.At 26min mark he reckons FB3.0s nozzle be usable
At 28mins he discusses what upgrades he uses.
Cyma available at Monkee mods

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M4a1 has the specific metal head and nozzle for it.

Get the 14t SHS Lee piston and the SHS nylon piston head And drill the tiny holes in it out to 2mm


I myself tinkered with my CYMA short and turn it into a CQB. Enjoyed working with the orange gearbox and turned it into 9:1 DSG build with M150 spring at this point. I got stuck with the Cylinder nozzle myself and eventually realized that CYMA nozzles are different when I chucked an ■■■■■■■ one-piece staino cylinder.
I used what M4A1 had as per post above but I’ve changed it to FB ( I think it was 3.0) Hope the pic helps

Hey Pewpew, thanks for that. I have found that it is not just CYMA that is alone with size fittings and this is probably where the final glitches lay when first timers do their mods. Heads and Nozzles are not the same and when you see them advertised, they say fits this and that, but it is all hit and miss dependent on the nozzle length and head alignment holes. Yes, getting the correct CYMA one will solve the problem with out doubt, but here in SA, two stores, neither will post and the one that is almost a 200km round trip has it. Sending it to the closer one where I can access it when I have physio treatment for my injuries, seems to be one of those can’t be done until head office approves it situations. I can buy online, but then I get the joy of paying $10-00 for postage for an item that weigh 5/8ths of FA. It is seriously FUBAR as far as I can see.
I’ll take my nylon one in and see what matches it in the off the rack dept, if they haven’t sorted this shit out.
Nice mods you have done to it, hardly recognise it for what it was, well done mate.