Jump to content

Recommended Posts

Modify Modular Gear Set & Cylinder Set Review


Back in July I posted some news regarding Modify’s new modular gear sets, and as promised they sent us a set to test. These are so new they could only send us one without the external packaging as these aren’t ready yet.


Now a lot of speculation has gone into the fit and how they work with the many types of gearboxes out there from the famous Tokyo Marui gear box to the infamous JLS. This review will try to separate the fact from fiction by testing it on as many gear boxes as possible.


Now this main review is on the actual Modular gear set and the new piston sets by Modify and it’s fitting into a 1st generation Version 2 Tokyo Marui Gear box, so all photos will be of this gear box. Due to the time needed to fit it in other brands of gearboxes only some images will be taken and no step by step review or fitting guide will be posted.


The Modular Gear Set


As you can see the set contains the spur, bevel and sector gear all contained in the fixing brace. The brace itself is made out of tempered stainless steel, resulting in a very stiff mounting, perfect for duress and tensions placed on these parts during operation.






One of the other features of the brace, is the tempered stainless steel bushes that are fixed on to the bracket, these have a double groove in them for oil, allowing the axle of the gears to rotate freely through these.




The whole unit is then mounted to the gear box using another set of bushings, these come in 6mm, 6.1mm 7mm with larger sizes in production for other high performance gear boxes and the only roll they play is to firmly hold the rest of the unit in place.




Also in the set is the anti-reversal latch and some of these features are an absolute godsend, the first feature is the added e-ring. This prevents the spring that pushes against the gear box wall thus engaging the latch into the bevel gear. There is nothing worse when building a version 2 gearbox to have the main spring release as you join the two halves together and the anti-reversal latch springing out as well, resulting in 15 minutes of looking for that damn spring.




The other great feature is the addition of a groove in the top of the anti-reversal latch allowing you to insert a Philips head screw driver and turning the latch out and away as you install the bevel gear.

( I personally think that selling this as a separate would be good business as I would personally appreciate these in other gear boxes.)




Lastly in the set is some synthetic lubricant with PTFE and is perfect for the bearings. Although there are probably much higher quality products on the market, the lubricant is good quality and very convenient for those of us that doesn’t have any in our kit.



Link to post
Share on other sites
  • Replies 82
  • Created
  • Last Reply

Top Posters In This Topic

Modify M4-A1 Cylinder Set


The Modify cylinder set is the whole deal and contains brass cylinder with plating, stainless steel cylinder head, POM air seal nozzle, polycarbonate piston and piston head. The packaging of the Modify set is very secure with enough packing to keep it safe even from moderately abusive delivery services.






Straight away when handling the Modify sets you can feel the quality and craftsmanship that has gone into producing the product. I would have to say straight away that the finish and quality is certainly up there with Systema cylinder parts and the finish of the brass plating is excellent.




The cylinder head is probably one of the nicest I have seen for a long time featuring double O-ring that really helps in prevents air loss on the forward stroke of the piston, while also securing the cylinder to the head. One of the benefits of this is that by placing grease between the O-rings cuts down on mess and also the grease being blown out of the cylinder during the first hundred or so shots. The grease stays exactly where it is needed, between the O-rings.




The dampening on the inside of the cylinder head is made from rubber rather than foam and actually does a better job as it doesn’t get compacted after time.




The piston head set is very well constructed and the thrust bearings allow the spring to spin freely removing the wear and tear that is inflicted on pistons without it. I would recommend though that users of thrust bearings should use lock tight or other thread locking liquids as the screw that hold the piston head set in to place has a tendency to unscrew it’s self.




Taking a closer look at the bearing it is made again to very good standards and the grooves on the outside are designed to catch grease, although I would recommend silicon spray over the grease as it allows the bearings far less resistance.




The piston as you can see uses the new 3 groove rails, if you aren’t aware of this the system prevent grease buildup at the front and back of the piston where it is then deposited into either the gearbox or worst still into the air nozzle which eventually fouls the hop unit and the barrel, resulting in a less effect hop and also decrease I accuracy and range.




Now one of the disappointments is the teeth on the piston, only the last tooth is metal. Now although this is perfect for us players using sub 1 joule weapons it does pose a potential weak spot for players able to take their guns to higher power ranges and adding the 3 groove rail system to the equation players looking to up grade might want to look at the non- 3 rail version.


Putting this aside though, the Modify piston is very well made and not being able to go above 0.98 joules this piston is perfect for both the high speed and high torque gear sets.




Finally the lowly air nozzle, this is 100% compatible if all variants and makes of M4A1 tappet plates and I was able to successfully mount it on Tokyo Marui, JG, JLS, Systema and a whole range of other 3rd party tappet plates.

Link to post
Share on other sites

Modify Spring and Spring Guide


Along with the Cylinder and Gear set modify also sent us a spring and guide, now modify certainly know their stuff and rather than sending the usual 90+ springs that a lot of companies send for us to test thinking that they will be under the 1 joule rule, Modify has actually conducted a lot of testing into gear, spring, thrust bearings setups and mixes allowing us to build a complete gear box as close to the 1 joule mark as possible without exceeding it. Excellent news for airsofter’s with little time on their hands for extensive testing, continuous tweaking and modifications.




The Rotary spring guide uses the same thrust bearing technology as the piston head allowing the spring to completely rotate on the guide. Now although this version of spring guide looks identical to the old Modify spring guide, there are some differences in design. The actual shaft of the spring guide also rotates assisting the thrust bearings but also the spring allowing it to return to its uncompressed state quicker and with less resistance, theoretically reducing wear and tear on the spring.




So now we have covered the individual parts, the technology and innovation, do they actually work and how well do they perform in a variety of gear boxes?


Putting it all together


Now as I mentioned at the beginning of the review, I’, not going to do a step by step guide for anything but the Tokyo Marui Version 2 gear box, although I will supply images and feed back on numerous other gearboxes and image will only be taken on areas of interest or concern.


The first thing I did was to insert the 6mm bushings in to the left hand side of the gear box, this was easily achieved but did require some pressure getting them to snap into position and lie into the grooves, used a small rubber mallet to knock the flat.




Now the next part was probably the easiest thing I have ever done when building a modified gear box (Pun not intended!) and that was to insert all the gears. It was a simple task of dropping the gear chassis into the bushings….done!




Now on a version 2 Marui gear box this was no problem along with a G&G and ICS, but on other gear boxes such as the JG, Echo1 and JLS where a lot of the time the holes made for the bushings are not aligned for standard gears, so how can you get this to fit?


Modify have been very clever with the chassis design as it offers enough support that you only need two of the three gear box mounts to fit. As the three gears make a triangle the Modify Modular gear set only requires two of the mounting holes on both halves of the gearbox to be aligned to guarantee a secure mounting for the gear set.




In the above picture you can clearly see that the top two mounts are aligned, due to the chassis bracket having their own bushings the bevel gear in the Jing Gong gear box is held firmly in place without requiring any bushings in the actual gearbox. Needless to say that due to the chassis bracket being made out of tempered steel you don’t need to worry about the integrity of the chassis. Not only that but you will also find that the motor now engages correctly with the gears now.




Next to go in is the anti-reversal latch, with the new design this is a joy to install compared to the original design. Again it’s nice to see a company that looks at a design that works yet manages to find away to make it better, and easier to install. Just place it on the end of a screwdriver and drop it in twist and it engages the bevel gear, done!




Next to go in is the cylinder, cylinder head and piston units, these fit in exactly like any other cylinder set and there is no trick or special way of in stalling these. Although I must say that the set fitted in the Version 2 gearbox very snuggly, very important for those not wanting to waste any air pressure.




Next to go in is the spring guide, even with me deliberately letting the spring fire out the back of the gear box with the spring guide, the anti-reversal latch stayed in place. Time to close up the gearbox, again this is where that groove in the top of the anti-reversal latch really helps allowing you to guide it into the top mounting hole. The gears slot nicely in as they are already aligned and held up right in the chassis




So how does it fire?


The whole gear box runs smooth as silk, the piston runs back and forth with little effort although the gear box does have a very distinct sound. Anyone who has used the Angel range of gears will understand what I mean and it is very different compared to the Marui Gear set. The out put is a constant 0.96 – 0.98 joules, which is absolutely outstanding!

Link to post
Share on other sites



I have to say this is one of the most innovative ideas and designs for gearboxes that have come out in a long time; it enables the user to quickly upgrade a gearbox with minimal fuss and confidence in the unit as a whole. Users wishing to upgrade non-aligning gearboxes finally have an answer to the problem, rather than spending many frustrating hours to no avail or substandard results you can now drop in a Modify Modular gear set.


Although it’s not all good news, the individual gears are not available as of yet and Modify have made no mention as to if they will release individual replacement gears. Also if you do get a lemon the inability to tweak the chassis could prove to be as frustrating as having to tweak a non-aligned gear box. So we will have to wait and see what the quality of the final production is like.




Easy to install

No fuss


Will fit all brands of gear box

Will work in non-aligned gear boxes




Currently unable to replace individual gears if any strip

No room to tweak gear set as it is a unit


Score and closing comments


I will give the Modify Modular gear set 8/10, all in all the unit is very impressive and like I said before one of the most innovative and creative ideas for the inner workings of gear boxes for a long time and I will certainly be looking out for future products from Modify.


I would like to thank the team at Modify especially Jane who was very patient in answering more torrid of questions and also for supplying us not only with the sample but also the information about the product in the first place.

Comming soon:


Review of the MagPul MIAD grip and CTR Stock.

Link to post
Share on other sites

fareast, brilliant review! any word on when/if a V3 set will be available?


also, please contact Modify and get them to release that anti-reversal latch! being able to rotate/allign it with the gearbox closed would be a GODSEND. so much so, i'm considering taking a dremel to my existing ones.... :unsure:

Edited by Tinkerbell
Link to post
Share on other sites
Great Review!


Looks like people that are unexperienced at putting gears back into gearboxes could reallydo with a set of these.


Not just the inexperienced, this thing is a huge time saver and not just to be written off by veterans as for "Beginners" this is a serious piece of kit for both the novice and pro alike.

Link to post
Share on other sites



Very well-written review. I think Modify did their research when they releases these parts as they addressed a couple of the big time consumers when it comes to gearbox construction: shimming and anti-reverse latch spring retention. One thing that interests me was the fact that the gearset is labeled with the ratio. I hopped over to their website (http://www.modify.com.tw) and after searching through their products listing, found the following information:


GB-09-11??Modular Gear Set for Marui Ver.2/3 (Torque 21.6:1)

GB-09-12??Modular Gear Set for 6mm gearbox Ver.2/Ver.3 (Torque 21.6:1)

GB-09-13??Modular Gear Set for 7mm gearbox Ver.2/Ver.3 (Torque 21.6:1)

GB-09-14??Modular Gear Set for Marui Ver.2/Ver.3 (Speed 16.32:1)

GB-09-15??Modular Gear Set for 6mm gearbox Ver.2/Ver.3 (Speed 16.32:1)

GB-09-16??Modular Gear Set for 7mm gearbox Ver.2/Ver.3 (Speed 16.32:1)


Link to source below.

[ http://www.modify.com.tw/Product_detail.as...41&F_ID=1000398 ]


Definitely a lot of potential here with this gearset, I'm curious to see a long term stress-test as I've been using Prometheus gears for a while and wonder if these would be a worthy alternative.

Link to post
Share on other sites
fareast, brilliant review! any word on when/if a V3 set will be available?


The JG GB he used above is a V3. FE was showing how it would work even in a 'non aligned' gearbox.


Great work FarEast! The photography alone was superb - right down to the carpet filament on the cylinder head :D



Edited by arivee
Link to post
Share on other sites

This is a lot better than I thought it would be - that cylinder kit, whilst pretty pedestrian as they go, still seems to be of very good quality - but I still worry about the bevel-pinion mesh issues.


And yes, that e-ring on the AR latch is a great idea - and that notch. Beats my usual method of filing the notch out with a set of files and a LOT of time. :D

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use and the use of session cookies.