95PGTTech 1/10 2WD ECX Ruckus build

[95PGTTech]

Rebuilt the front shocks (using the 4WD ones) by taking 10mm of travel out so it doesn't any longer bind the steering on full extension. Found metal lower shock ends that will work, and using a 2WD aluminum perch with a 4WD upper perch cut for a slot and glued to it so it holds the larger 4WD spring tight. I searched high and low for a perch from another model that would work, no dice. It's bigger diameter than a 2WD, but narrower than a Traxxas and other manufacturers springs. The solution is probably to just swap the upper and lower perches and trash these springs, or do like we did on our 4WD and go with a completely new unit.

The side by side pic is 4WD stock shock right, 4WD shock with 10mm spacers, rod end, 2WD modified perch on left.



It makes the ride height (with the bare minimum preload to keep the spring perch from falling out, can't go any less) no bueno. So we ended up putting the 2WD springs on the 4WD shocks with a 2WD unmodified upper and lower perch, and got this.



Final pics are the mock up of how we are replacing the stock transmission to rear shock tower brace and transmission to rear bumper brace (for us, now wheelie bar not rear bumper). Yes, that is a 3mm drill bit in the rear bumper...I didn't have any M3 long enough on hand to mock something up LOL

 

[95PGTTech]

New hardware came in, got a chance to wrap it up and loctite everything (no more 3mm drill bit wheelie bar mount LOL). Ran one battery through it on a weather break. Only thing we broke was loosened up the right rear wheel and lost the wheel nut and washer.

Thoughts: new trans will send power to both tires HARD under all circumstances. Did not seem to appreciably affect handling. Being all metal, was pretty quiet too. All tires other than Badlands suck by comparison. Even these Proline Trenchers were ice skates.

Have some Bandlands on the way now for it and some aluminum hubs for the front Raid wheels. Maybe we will hit this thing with 3S again when they get here. Trans mounting system seemed just fine.

 

[95PGTTech]

*mostly* good day. I can't keep this thing from spinning wheel hexes inside the wheel hubs. I guess tomorrow I could try the stock wheels again to see if it's an issue specifically with these Raid wheels, but since it's NOT happening in the front, I think it's just a function of too much power and too much traction. I have aluminum wheel hubs on the way.

Another bad thing was hitting ESC temp cutoff. Measured it 170 when it cut out after 8 minutes on 2S with 87 ambient outside, probably a 30 second cooldown in that run time. I don't think since stock we have run one entire battery through this thing without needing to stop for one reason or another. Modified life I guess. The trans works great. I wrote it down but not sure if I mentioned it here it comes with 20T pinion and 87T spur (48p) out of the box and it doesn't say that in the tiny bit of literature anywhere so maybe I'll save someone from sitting there counting teeth like I had to (they are not marked either like most aftermarket metal gearsets). I have the 21T pinion in there now. The ESC fan arrived. It bolts on and connects to the ESC plug fine just like the instructions say but doesn't work. At all. I powered just the fan up with jumper wires to a spare battery and the fan works and the ESC measured 7.4V DC output between the + and - terminals of its diagnostic port with the ESC on and zero with the ESC off so I'm kinda stumped. I even left it on for a minute thinking maybe there is some sort of delay between when the ESC turns on and when it commands the fan on. I emailed the manufacturer.

And we bent the poop out of the motor to wheelie bar mount, LOL. The few times that the wheel hexes don't strip this thing hooks HARD and obviously loads the bar well. M3 was no match. Positions 1 and 2 of the wheelie bar are too low to be of any use so I probably just need to redo the whole thing. But when we weren't turning wheel hubs into melty plastic messes, both the truck and the wheelie bar work GOOD. I attempted to go back to the narrow H-R hubs in the back thinking I just wasn't getting enough engagement on the axle threads, which seemed to help for a minute but eventually failed again. Added more preload to the rear suspension to get the ride height where we wanted and made other small changes during the shakedown today.

 

[95PGTTech]

Dialed up my robotics engineer brother (that’s his literal job, he’s the smart one) and went over some diagnostics with him and sent him some pics. He suspected intermittent/incomplete circuit break, and further diagnosis confirmed it. So I tore into it. I haven’t found a smoking gun yet but I really need to take it to his work where we can clean it up better (safely) and get it under a microscope and a trained eye. I have a 10BL120 I’m going to put in for the interim, and I ordered a 3674 because this motor doesn’t have the right banana plugs for it. The correct motor will be one that makes a TON of torque down low to further spin wheel hexes and bend wheelie bars, right?

 

[95PGTTech]

Mixed bag today. Fixed a lot, broke some more, fixed it. Still stuff to mod and adjust. At the end of the day, he and I had some fun, and the truck is in one piece for another bash session and tuning tomorrow. Which is better than a lot of days.

We started off replacing six Proline hubs with our afternoon snack today - that’s how many we destroyed yesterday trying to diagnose and fix issues. We think one may be the washers we custom made for the raid wheels. One may be older/worn axle nuts, and one definitely is a left rear inner wheel bearing that went so bad the axle is mating with the hub carrier (and the hardened steel axle is winning big time). A bunch of new hubs arrived including some aluminum ones but for now I put my stockpile of extra narrow offset hubs to use for testing our fixes. We use almost exclusively the wide offset. Because track width, duh. We think we solved it between those 3 things, but I have a 12-17 hex adapter kit on the way just in case problems persist. Proline 3.8s would probably look NUTS on this! Or a big/little setup!

With the Tazer esc down for repairs I put a 10BL120 in it for now. It has 4mm banana plugs on it already it was powering a 3660 GoolRC motor so I’d need adapters anyway so I just ordered the 3674 everyone raves about. I’d like to keep the Tazers as a matched pair anyway they work well. The 3674 does not come with a pinion I had 20, 21, and 23 on hand in 5mm 48p hardened so I went with 23. Id rather have the top end than keep compounding the wheelie problems, the 74 is going to likely make that even worse.

I’d really like to move this ESC up front, why did they put everything so far back on a RWD model?

 

[95PGTTech]

Attempted to use the heat wrench to get the hub to loosen up and allow me to get the outer race out. Wasn’t happening.



That sweet Chinesium alloy just bonded to the outer race when the bearing got hot and wouldn’t let it go. The alloy is so bad you can see where it deformed like butter from me prying on it (using something to brace against it too!). Threw a stocker in it because I really wanted to get some shakedown in and ordered up a replacement set.

I think ditching that washer I had under the wheel locknuts helped. It was probably not allowing the locknut to bite into the wheel hub (we use those fancy aluminum locknuts with the reverse cut thread). Had no wheel hubs destroyed today. We have enough thread we can probably go back to the wide wheel hexes.

Fan on ESC, ready to shake down

 

[95PGTTech]

The day I installed it with a 3650 21T

Today, after not even two full 2S lipos, half on a 3674 23T

Noisy
Input shaft has endplay
Spur when viewed from behind has runout especially at low speed
There is pretty good gear mesh and spacing even after running it and no super abnormal tooth wear pattern, but the slipper assembly behind the spur looks like crap and the whole assembly generates a very fine metallic dust constantly. I zoomed in to make sure it couldn’t be the axle against the motor plate. Uhoh!

Emailed the seller and got told maybe it needs to break in. LMAO. My experience in racing has always been that internal metallic shavings always immediately precede a spectacular and catastrophic internal failure. A new one is on its way, so tomorrow we may send this one to the moon. I do have the adapters to put some of my 2S in series and this 3674 is rated for 5S…

 

[slick2500]

Put a piece of Gorilla tape or aluminum tape over the rear bearing on that motor, it helps them last longer.

 

[95PGTTech]

Put a piece of Gorilla tape or aluminum tape over the rear bearing on that motor, it helps them last longer.

Over the brass hex? I did realize that had rocked loose a half turn left so and tightening it did help input shaft endplay. I might tear down the the new one and take a look through it. This one I just opened the box and installed (per instructions). Another odd thing is it was sent with the slipper full tight (most come either set to the normal 1 turn out or full loose to preserve the spring). I did back it out to 1/2 turn from loose before running it which is the same setting I have for both our 2wd and 4wd trucks. It’s a little tighter than most say they run, but it’s what achieved the settings all the videos said I should shoot for of wheelspin slip and the stand on rear tires apply power method

 

[slick2500]

Over the brass hex? I did realize that had rocked loose a half turn left so and tightening it did help input shaft endplay. I might tear down the the new one and take a look through it. This one I just opened the box and installed (per instructions). Another odd thing is it was sent with the slipper full tight (most come either set to the normal 1 turn out or full loose to preserve the spring). I did back it out to 1/2 turn from loose before running it which is the same setting I have for both our 2wd and 4wd trucks. It’s a little tighter than most say they run, but it’s what achieved the settings all the videos said I should shoot for of wheelspin slip and the stand on rear tires apply power method

No on the end bell of the motor, the bearing is exposed.

 

[95PGTTech]

No on the end bell of the motor, the bearing is exposed.

View attachment 7883View attachment 7884

Oh good call, I’m on it. Good bash day. Destroyed the Axial trans in session 1, swapped in our built spare stock style trans, had a good time session 2. Broke cosmetic/stupid stuff, nothing major

 

[95PGTTech]

In true Roadkill fashion, knowing we likely had a hurt trans, we took it out for a bash session, put a more agressive pinion in it and my best 100c 3s battery and tried to send it to outer space. I looked up the motor and ESC, 4S is a no go on this ESC (I could on the one I put in the 4WD Ruckus).

After about ten minutes he did one giant wheelstand and we knew something was up when it set the front end down really abruptly, and we found it had sheared off the output shaft at both axle pins. Was it the constant merciless wheelies on a high traction surface, was it the jumps (we don’t normally ramp it), or something inside go boom?



Got the trans out and after taking the motor off it actually rotates decently smooth so nothing inside must be THAT bad. A little shavings in there but could have been from the final failure. Gears look good. No metal on metal witness marks, bearings look ok. All the shavings/dust are under that outside cover. Slipper spring feels like it’s binding up on the nut. All hardware was tight. No shiny witness marks to say smoking gun that’s what was rubbing. A few marks on the red anodized cover but I think that was when the axle broke and flipped around.

I’m thinking slipper clutch at this point. I adjusted it before we went out using the stand on rear wheels and give it throttle until it wheelstands and slips method. It was really weird it wanted 1/2 turn out from full tight again, even tiny adjustment out more would be such bad slippage the truck was a permanent neutral and any tighter (even like an 1/8 turn) it would try and backflip zero slip. Something wrong with it making all that dust, could explain breaking both output shafts on a hard jump too. Whatever, not my problem, just gathering data and input for the seller.

 

[95PGTTech]

Most NORMAL families do not have a built, refreshed spare transmission ready to go "just in case," but race families aren't exactly normal. Normal families also don't install it at the dinner table together while having lunch, so...



Look how much track width I'm giving up right now with the narrow wheel hexes and narrow wheel hubs in the rear, this is depressing



The Traxxas 12-17 conversion kit came in and I was able to confirm it would fit correctly (the rear at least, where we are currently using Traxxas axles). This was both to give us an option if stripping the wheel hexes continues, and as an option to go to heavier/larger diameter 17mm wheels/tires.


Our second session went REALLY well. The stock trans with 30k diff oil doesn't perform terribly compared to the locker, and it does seem to turn better. We did pop off the right rear camber link eyelet and the wheelie bar upper right mounting screw on one bad tumble after a bad landing from a jump, but they went back on okay in the field. We also knocked the LED bar off the roof when he went under a bridge too low so to speak. Overall, probably our least destroyed-important-stuff session. On 3S, I was really imrpessed we have a bad history of absolutely FUBAR stuff on the big batteries. I added some videos to that how to thread I made about the wheelie bar.

https://www.ecxforum.com/threads/how-to-2wd-wheelie-bar.3333/#post-24690

 

[95PGTTech]

The Prolines got sexier. Aluminum 12mm hubs arrived. I'm going to get another set for the front, that's a 60 gram difference! I changed out the black hardware that comes with them for m3x16mm button head stainless to match the color of the hub. I had socket head and recessed head too, this is the one James (and more importantly the wife) voted for. I think they made a good call, I can't wait to see the matching set on the front.



Another way I can get more weight in the front would be to go to the belted version of these when they wear out. I measured these at 13oz for the pair and the belted PRO1017410 are listed at 13.9 and the belted 3.8s (PRO1016610) are over 30oz (not to mention 6.8 tall versus 5.05 tall) - then add the aluminum hubs (they make 12, 14, and 17 alum hub kits). I think losing the 12mm brass hexes would be mostly offset by the adding of the 17mm conversion kit. I'm not willing to go back to the RPM lower arms in the front, we're talking a few grams at best traded for a ton of slop and ugly AF. I already looked at cutting up some stuff to slide the battery even further forward but it's not going to be much before I hit the steering servo. I am exploring bringing the ESC up front by the transmitter. If all that or a combination of that doesn't work, I really have no choice - add weight with a weight bar. The racer in me really, really, really doesn't like adding ballast unless its an absolute last resort, but I have to get this thing off the wheelie bars somehow. The goal is softly touch them and softly set the front end back down and slingshot, currently we have rock back hard on them and stay pinned back on them under power.

 

[slick2500]

In true Roadkill fashion, knowing we likely had a hurt trans, we took it out for a bash session, put a more agressive pinion in it and my best 100c 3s battery and tried to send it to outer space. I looked up the motor and ESC, 4S is a no go on this ESC (I could on the one I put in the 4WD Ruckus).

After about ten minutes he did one giant wheelstand and we knew something was up when it set the front end down really abruptly, and we found it had sheared off the output shaft at both axle pins. Was it the constant merciless wheelies on a high traction surface, was it the jumps (we don’t normally ramp it), or something inside go boom?

View attachment 7890

Got the trans out and after taking the motor off it actually rotates decently smooth so nothing inside must be THAT bad. A little shavings in there but could have been from the final failure. Gears look good. No metal on metal witness marks, bearings look ok. All the shavings/dust are under that outside cover. Slipper spring feels like it’s binding up on the nut. All hardware was tight. No shiny witness marks to say smoking gun that’s what was rubbing. A few marks on the red anodized cover but I think that was when the axle broke and flipped around.

I’m thinking slipper clutch at this point. I adjusted it before we went out using the stand on rear wheels and give it throttle until it wheelstands and slips method. It was really weird it wanted 1/2 turn out from full tight again, even tiny adjustment out more would be such bad slippage the truck was a permanent neutral and any tighter (even like an 1/8 turn) it would try and backflip zero slip. Something wrong with it making all that dust, could explain breaking both output shafts on a hard jump too. Whatever, not my problem, just gathering data and input for the seller.

Was this one of the Aliexpress/Banggood/eBay special units from China? I've always heard mixed things about the Axial trans so I never went that route.

 

[95PGTTech]

Was this one of the Aliexpress/Banggood/eBay special units from China? I've always heard mixed things about the Axial trans so I never went that route.

Yup, Amazon Prime $35 2 day. Same one guy uses in that YouTube video I linked. I was skeptical, but over 400 written reviews with a 4.2 star is pretty damn convincing (better than any RCAWD or H-R part LOL). Found other guys retrofitting it into other stuff. Some reviews said all stainless hardware and mine definitely wasn’t some said packed with grease mine wasn’t so maybe there are multiple slave shops cranking these out. As with most China parts there are reviews there 1 star complete junk. Guys getting them missing bearings, broken pins out of the box, etc. Guess I’m in that group and got a junk slipper out of the box. I’ll tear down my one (I’m assuming you only get one) new free replacement and look it over before install. If I really fall in love with this trans, “reputable” companies like H-R make one.

 

[95PGTTech]

Really crappy day out, not worth risking the electronics or even just the sheer cleanup. James and I went out and stomped in mud puddles instead. I did some boring work during his nap - changed up some ESC settings, aligned it (-2 camber at all corners, zero toe front and 1/4 toe in rear non-adjustable). Got some wiring organized better, and added 12mm standoffs to the ESC tray and 15mm standoffs to the battery hold down so I can go back to using the stock setup with the 3S and not zip ties because I think that’s the battery that’s here to stay. Added a little more preload to the rear and moved the shock to the most vertical setting.



Replacement AX10 trans came in. I’m not in a hurry to throw it in with the stock style build working this well. I did take it apart and check for obvious bad crap out of the box and didn’t find anything major. The slipper on this one came cranked down all the way so I loosened it up and threw a washer under the nut.

 

[slick2500]

Yup, Amazon Prime $35 2 day. Same one guy uses in that YouTube video I linked. I was skeptical, but over 400 written reviews with a 4.2 star is pretty damn convincing (better than any RCAWD or H-R part LOL). Found other guys retrofitting it into other stuff. Some reviews said all stainless hardware and mine definitely wasn’t some said packed with grease mine wasn’t so maybe there are multiple slave shops cranking these out. As with most China parts there are reviews there 1 star complete junk. Guys getting them missing bearings, broken pins out of the box, etc. Guess I’m in that group and got a junk slipper out of the box. I’ll tear down my one (I’m assuming you only get one) new free replacement and look it over before install. If I really fall in love with this trans, “reputable” companies like H-R make one.

You have to take Amazon reviews with a grain of salt, most 5 star reviews are bogus as are some of the 4 stars you have to read the 3 star and lower reviews to actually get a good impression of the items. And yeah it sounds like there are some inconsistencies in what you actually get.

 

[95PGTTech]

Good day, took Ruckus to the park where we fooled around in the parking lot for a few laps since it was empty, then walked the trails for a half hour (it's pretty funny to see James walking next to it like the RC is his dog), did some varied terrains back there in the trails that are probably better for a 4x4 crawler, hit the playground, then with nothing to lose really sent it in the parking lot. Didn't bother to GPS it, don't care on this surface. To the eyeball, it was as close to as fast as this truck has ever gone and maybe approaching the 50mph (grass) of his 4x4.

Nothing major broken, battery was still at 3.8 per cell after almost an hour of use (albeit most of it very light but still). Learned how important quality AA batteries are to transmitter function/range. Motor and ESC were ice cold all day barely warm to touch didn't even bother IR gun. Not doing much to it for now with the 4x4 under major construction, this thing is pretty good and reliable as-is. Brought it home, cleaned/blew it all off and checked for problems, charged the battery and ran it again in the afternoon on grass again. Motor got slightly warm but it was also 95 ambient and in direct sun and in tall tall grass.

Right rear camber link did pop off again. Once on a cartwheel in the parking lot at the park and popped it back off. Cleaning it off after the second session noticed BOTH had come off just not completely. I think I see them hitting the new aluminum rear shock tower so we will have to address that I guess with some thin spacers. I'm going to throw some stiffer springs in the back to try and account for all the weight back there. As you'll see in the video no shock on earth is going to help this thing right now, it simply needs weight added to the front (or preferrably, weight relocated forward. Bit of a rear wheel play issue to inspect too, going to take another look at those bearings. A lot of play in that left upper camber arm mount to the stock hub - the H-R replacement arrived today so those will go in. We lost a wheel nut on the left rear in the grass today but thanks to those aluminum Proline wheel hubs it was just throw on another wheel nut and go.




Rear wheel play video. Checked wheel nuts, tight. Suspect bearings.

 

[95PGTTech]

Little video I clipped together from today. Wheelies on high traction surface makes it pretty obvious it's not a shock/weight transfer issue if the truck rocks it back on the wheelie bars and pins it there with power, its an issue of simply the nose doesn't weigh enough to ever come back down. I have the aluminum hubs on the way for the front wheels, but then it's pretty much just build an adjustable weight bar for it and get it as low and as forward as I can while still retaining some ground clearance.