My maxx 4s!

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olds97_lss

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Location
Dekalb, IL
RC Driving Style
  1. Bashing
I sold my savage flux to help fund buying one and picked it up last week. The first new RC I've had since 2018.

I replaced the motor/esc with a MMX/2200kv sensored system as well as the receiver to spektrum since that's what I run in everything. I'll leave the stock servo for now.

I've put a set of RC Station 3.8" LP wheels/tires on it off my stampede as they put too much strain on that. Now that I have a proper 4S machine, I can dial the stampede back a bit so it's less likely to destroy itself.

05/17/2021 - When I got it:
2021-0517-maxx-top.jpg

2021-0517-maxx-side-body.jpg


05/19/2021 - By Wednesday, I had the red widemax kit installed and started installing the MMX/2200kv system:
2021-0519-maxx-wideKitInstalled-MMX-2200kv-testFit-side-high.jpg


05/20/2021 - Thursday I put the RC Station wheels/tires on it:
2021-0520-maxx-RCStation3.8Tires-front.jpg

2021-0520-maxx-RCStation3.8Tires-side.jpg


05/22/2021 - By Saturday, my NHX dual fan cooler showed up as did my 3 port servo splitter for the fans:
2021-0522-maxx-electronicsInstalled-top-closeUp.jpg


05/23/2021 - Yesterday, the tube of E6000 showed up, so I meshed/goo'd the body in hopes to help it last longer:
2021-0523-maxx-BodyMeshedE6000-01.jpg


The duct brand mesh tape sucks. Doesn't stay put at all. When this body gets messed up, I'll likely replace it with a probodyrc body as I've had really good luck with those the past couple of years on other trucks.

For now, I'm sticking with stock gearing, 24/50. The RC Station tires are a bit larger OD than stock, so I should get similar speeds with the 2200kv vs the stock 2400kv.

If the tires/wheels hold up, I'll likely get a black set as the orange is just jarring to look at with the "red" maxx. Wish they had had orange in stock, then it would have looked better.

I have a couple liperior 4S 65C packs coming this week that I'll be using in it. I had to dremel out the battery bay to fit my lipo's in it that I built out of old hobbystar 6200mah 3S packs that I've been running in my stampede. I have a couple 3S 65C liperior's and they didn't fit either without modifying the chassis a bit. I'm assuming the 65C 4S liperior's will be similar width.

These are the tires compared to stock, 3.8" trenchers and 2.8" trenchers for reference:
2021-0520-trencher3.8-RCStation3.8-Maxx4S-trencher2.8.jpg


I did buy a full set of axle carriers/c-hubs as take offs on ebay. I know the c-hubs are weak in the front, so figured it would be a good idea to have a set on hand.

I haven't driven it yet. Well, I haven't bashed it yet. I ran it in my parking lot a couple days ago at 10pm after finalizing the electronics installation. I have the punch on the mmx set to 75% (which for castle means 75% limited, so 25% punch). I'll likely leave it at that for now since I still have the plastic axles. I'm not sure how they will hold up, but after having the v1 e-revo with plastic axles for 3 years on 4S, I'd imagine these will hold up as well as they look similar in size. Will find out I guess.

When installing the widemaxx kit, they suggested increasing the rear oil to 50wt. After reading some posts at traxxas forum, it seems that 50wt front/70wt rear is a good all around setup for jumping while not being overly stiff, so I may change to that before next weekend. The front does feel very under dampened.
 
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Can't wait to see your latest video @olds97_lss ;)
I'm really chomping at the bit to launch this thing... The longer it sits, the more I change on it.

Today I changed out the shock oils after reading some info on the traxxas forum. Those that like to jump prefer 50wt in the front and 70wt in the rear, so that's what I changed it to today. I'm on the verge of tearing out the center diff and throwing 500K in it just because of posts I've seen regarding the 20M in it... but I think I'll drive it first. I thought 20M in my ERBE v2 was too thick, but after a few minutes, it loosens up. Guessing this will do the same, albeit it's being shorter, lighter and the tires are lighter...

This is why I don't buy trucks in the winter... By the time Spring rolls around, the entire truck is so far removed from what it was, that I have no clue if I even like it in factory form!

I have this nagging feeling though that I'm going to snap an arm off or something on my first jump... lol!
 
Ugh... this thing is like driving a blind cat! The servo saver spring is so soft that it may as well not be in there. Will be a while before I have video of it... I goofed up the camera and set the exposure mode too high, so even though it's cloudy out... it's painfully bright a lot of the time. :(

All I have now is the skidplate wear after running just 1 pack at my concrete bmx track... screw heads on the rear are already almost toast:
2021-0525-maxx-SkidPlateWear-DekalbSkatePark-1Pack-close.jpg


That's why I make steel or titanium wear plates for the trucks I run there... guess this one is no exception!
 
I made a 2mm or so thick spacer to compress the spring a bit more. Pretty sure it was an old shock clip from a savage. I had a bunch around for the stampede, but got annoyed at the package they were in and since I threw away the ultra shocks a long time ago, I think I threw those away as well.

Will see how compressing the spring a bit helps. Feels stronger on the bench.

There have been 2 or 3 screws for things I've taken off and put back on that have been stripped out threads already. I've been overly careful since everything is plastic. One of which was one of the screws for the steering top plate hold down on the outside edge. The other is the large screw that goes into the motor plate. Can't recall the other, but there was a 3rd.

With the steering top plate, I just drilled both holes through the shock tower completely and put in a longer screw, now they both have bite.

Footage from the first run with it:
 
I wish i had something like that around where I live to play on!!! That last landing I felt in my bones lol
 
Actually, that wasn't the worst landing. There was another right after that, but I blurted out a few choice words and I didn't want that in my video.
 
My second run with it:

I had put a set of traxxas 3.8 chevrons on it on 1/2" offset geode wheels for the first pack. Wow, do those tires suck for traction in the grass! For the second pack I put my backflip MT's on it from my e-revo 2.0. Way better grip, but the tires felt a bit large for it.

I've since installed a treal servo saver, which is a really nice piece and stiffens up the steering considerably:
2021-0602-maxx-TrealServoSaver-takenApart01.jpg

2021-0602-maxx-TrealServoSaver-installed02.jpg


I changed the battery hold down to one that uses velcro so I don't have to fiddle with spacers to run the different sized packs I have.

Today some stuff showed up for it:
2021-0604-StuffForTheMaxx.jpg


I wrapped, balanced, vented and mounted up the new wheels/tires (Backflip LP's and traxxas 8671 wheels):
2021-0604-maxx-backflipLP-body-side.jpg


I'm using axial 31087 flange nuts instead of the stock nuts/plastic disk things. I used those on my savage flux a long time ago and they were super beefy. I could only find 2 of them though, so I had to find them again.

I have also changed out the 20M center diff "fluid" with 500K to see how I like that. The 20M was almost like having a spool. Hoping the 500K isn't too light, but will find out.

I'll install the new servo when the stock one dies. I run that servo in both my outcast 6s and e-revo 2.0 off max6's at 7.2V and it does a decent job for $40. Also got the red fan to match the color scheme... but didn't feel like messing with fans and will put it on the MMX when that fan dies.
 
More stuff... added a 3x1800uf cap pack, treal front c-hubs, traxxas steel cvd's, moved the esc switch to the receiver box so it is less likely to shut itself off on a hard rear landing. Also lowered the center diff to 200K.

2021-0712-maxx-treal_C_Hubs-low.jpg

2021-0710-maxx-6SLiperiorInstalled-top.jpg


Also committed to running 6S in it. Can't quite get the speeds I need to run at the grass bmx track on 4S without overheating the motor.
2021-0712-maxx-CNHL40C5000mah6Sx4-TrealBlackC-Hubs.jpg


Dropped the gearing down to 22/50, dialed the punch down to 75% limited, brakes to 30%. Did those changes after running it on 6S on a pack I made out of a couple liperior 65C 3S 5000mah packs.

Short video of the first 6S session testing it out:

It's a bit of a handful. The center diff actually acts like a diff now on 6S. Didn't notice it as much on 4S, even with 200K in it.
 
She looks great! For a minute I thought she was going to go right through the fence and into the parked car! :eek:
 
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