KWA EVE-4 First Impressions

[Speedbird_666]

mine is working fine and I’ve only swapped out the hop rubber.

Cool story bro.

if it’s not broken why fix (imo)

Did you actually read what I posted? It was broken.

Particularly the post first game use report - where the gun ran so hot it became unusable, the weird velocity issues and the trigger switch that was in self-destruct mode - all of which I have fixed.

One look on the KWA Owners group will show that the stock piston is one of the most common points of failure and the first thing replaced - sometimes within a couple hours of use. Then there's the massive tappet-timing issue that will cut the power output in half as the nozzle and tappet wears.

I'm glad yours is working fine. There have been plenty that haven't - right out of the box.

I stand by what I've said - not recommended. At all.

 

[zknightzero]

Hi there @Speedbird_666,

Really detailed thread! I just purchased a KWA eve 4, which has the following upgrades:

Maxx hop up

Gate titan II bluetooth

CNC adjustable trigger

I've noticed the stock motor and batteries are running hot on both 25 and 30c 11.1v batteries, do you think it's worth swapping out the motor first and what would you recommend? Would this be too much torque / speed: https://www.ak2m4.co.uk/xt-high-torque-motor-28tpa-long-fan

I haven't quite decided on whether the Piston and Piston Head is also worth upgrading at this point too. 

Many thanks!

 

[Speedbird_666]

I've noticed the stock motor and batteries are running hot on both 25 and 30c 11.1v batteries, do you think it's worth swapping out the motor first and what would you recommend? Would this be too much torque / speed: https://www.ak2m4.co.uk/xt-high-torque-motor-28tpa-long-fan

I haven't quite decided on whether the Piston and Piston Head is also worth upgrading at this point too.

Hello there - welcome to the forums.

28TPA works fine in my testing - runs much cooler and draws less amps. You will get a slight full-auto ROF reduction though - which is no bad thing with the tappet timing. The extra torque shouldn't be an issue with the stock gears.

I would recommend replacing the Piston and Head. The all-plastic pistons don't seem to last long - a common complaint with KWA guns.

Gate Titan II - make sure you have the latest firmware as there has been issues with the way that the Titan II (but not the original Titan) 'sees' the sector gear teeth in the firing cycle with the additional sensor fitted on the board.

 

[zknightzero]

Thank you for the welcome, would you suggest any other motor to keep the ROF up? I understand that there's a trade off with ROF / Torque and that the gears would likely be the change if I wanted to increase the ROF.

Ironically I bought a warhead 52k motor but this seems to have chewed up another build of mine that's in the shop since I messed it up, so I'm afraid to throw it in this build.

I'll purchase a madbull px02 and ZCL piston head: https://www.ak2m4.co.uk/zci-piston-head-double-oring?search=Piston

Thank you for the suggestion, I'll ensure I keep the firmware up to date. 

 

[ak2m4]

I'll purchase a madbull px02 and ZCL piston head: https://www.ak2m4.co.uk/zci-piston-head-double-oring?search=Piston

Currently out of stock on the single oring aluminium piston heads - more arriving end of the week. 

Really Double O-ring piston heads aren't worth the added cost in reliability and bring nothing to the table.  Will remove this from the website just reminded me.

The POM-H piston heads with the Viton orings are currently the most requested / purchased right now so worth checking out

Also I'm not sure about the Madbull PX02, generally a lot of retailers are pulling away from the wide rack design due to it causing scratches on the inside of cylinder.  Not sure if that type of piston is a requirement for that KWA?  £20+ for a wide-racked MIM piston doesn't make much sense to me unless it's a compatibility thing.

 

[zknightzero]

Thanks for the update @ak2m4. I'm quite new to all of this, would you suggest another piston, head and motor from your site? I'd prefer to get it all from you rather than sourcing parts elsewhere. 

 

[Speedbird_666]

@ak2m4 It's a compatibility thing unfortunately. The PX02 is the closest metal-racked piston to the stock KWA in terms of dimensions (the GB is fractionally oversized to standard V2). It was a heartbreaking purchase - £30 for a piston delivered...? BUT it fits the GB perfectly - minimal lateral/vertical movement but moves freely on the rails.

@zknightzero I would suggest the AOE version of the XT Piston head - the AoE needed correcting on my gun - I don't normally bother with AoE corrections in general, but this gun needed it. You might also have to shave the second to last tooth down for clearance - a couple of minutes with a file should sort it.  Oh, and almost all of my guns use POM piston heads from AK2M4. Much prefer them to the aluminium types.

 

[zknightzero]

Thank you both, should be here by the end of this week. I'll give it a fix on Saturday and let you know how it goes!

 

[ak2m4]

Thank you both, should be here by the end of this week. I'll give it a fix on Saturday and let you know how it goes!

Hopefully arrive tomorrow for you.  Keep an eye on your email for a RM tracking link.

 

[zknightzero]

Thank you for the fast shipping @ak2m4 

So as it turns out, after ordering the madbull piston, shims and motor, all I really needed was the motor!

My original concern was how quickly the motor heated up as well as the battery. When I opened it up, I noticed the piston doesn't look stock - this wasn't mentioned in the listing when I purchased it. They had mentioned a tech put in the new nub, titan and trigger, but nothing else:

View attachment 111185

Whilst the piston head wasnt the best, as it is stock, i suppose if it isn't broken don't fix it. The teeth on it look ok. However, the AOE looked a little odd at first:

View attachment 111186

Although depending on how you look at it, it's not too bad, especially when you match the next set of teeth, and consider that the previous tech put in sorbothane padding in the cylinder:

View attachment 111187

Whilst you could shave down that first tooth, the clearance seems fine. I figured I would trust the work that's already been done to it rather than complicating it further. But I will heed your advice @Speedbird_666 - if something seems off in future I'll replace the piston head as I now have the parts to do so!

I have noticed since putting it back together that the safety selector is a bit dodgy, I'll rectify that at some point this weekend. 

I'm new to this sort of tech work so let me know if you think what I've decided is garbage or not lol

 

[ak2m4]

looks like the 1st tooth (the big thick one) is a little high, it could be rubbing against the top of the sector gear, but I've got zero experience of the eve so might just be a "thing".  However is easy fixed grinding it down.  you're right though perhaps leave it for a few games and see how it performs.

 

[Reflxx]

Late reply to this thread , figured I’d ask if anyone was still checking this thread , from what I’ve gathered I’m planning on putting in a MAXX hop , with an sr10 tapper and a maxx 21.25 nozzle . Paired with a gate titan , mad bull piston and dt AOE piston head , still unsure on what motor and gearbox ratio I’m looking at though any suggestions? Also , has anyone checked out the gearbox and knows if I will have to do any shimming? ( that is without changing any motor or gears)

 

[zknightzero]

@Reflxx I've got a spare madbull if you're interested. As for the rest I'm not sure to be honest, it seems to be working just fine at the moment, but accuracy could do with some work so I was wondering what hop up could work with it, being that the original does look proprietary only.

 

[JuggyUK]

Apologies for resurecting this thread.

I have a KWA Eve-9 with Gate Titan installed, I need to pull the gearbox apart to clean some dirt from the Titan sensors and would like to install a few upgrades while I'm about it.

From reading this thread I gather the following upgrades are best.

SHS motor (high speed or high torque?)

XT piston head

Madbull Piston

Anything else worth doing? I do not mind spending a bit of cash on getting it running nicely.