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AX10 Scorpion RTR turned NMRCC Trail Class Build

After some consulting with @WHITE-TRASH I decided to build a Capra axle for the rear to get overdrive since it was about the same cost as overdrive transmission options I was looking at, but had the added benefit of more ground clearance. He also recommended me a cheap carbon fiber chassis off Amazon to move my drivetrain forward to to help my forward weight bias as well as get my truck lower. I also abandoned the idea of running water in my tires and went to a foam setup.

I decided to weigh the SCX10 chassis setup as well as the transmission while I had everything apart.
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Axial 3-gear transmission with a 93T 48P spur gear sans motor, 86g:
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I used a stock Axial Capra housing (AXI232005), Axial hardware (AXI235016, AXI235014, & AXIC3165), Axial stub shafts (AXI232008), SSD 27T/8T overdrive diff gears (SSD00349), SSD Locker (SSD00196), Treal 19T/16T Overdrive portal gears (X0034LUD9B), Vanquish axle shafts (VPS08083), and a TRB bearing set (140041).

With the overdrive diff gears and overdrive portal gears, my rear axle ratio works out to 4.01 vs 3.31 for my front axle which is about a 21% overdrive on the front.

The new parts:
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I needed a much longer rear drive shaft for the new chassis, so I bought another one from Injora since they are cheap and all metal.
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The foam setup for the Ruptures. I ended up using the foams that came with the Ruptures in my Moabs and they seem to work perfectly in the Moabs.
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The chassis rails I used. Link to the cheap Carbon Fiber Amazon Chassis
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The Capra/AR44 axles have a 1.063" ring gear vs 1.482" for the AX10 axles. I was concerned at first about the durability compared to the AX10 axle, but it has held up great.
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I am not sure why this was the case, but the SSD pinion had some clearance issues with the SSD locker. I just chucked the locker up in my cordless drill and sanded that side of the locker down a bit.
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The other big issue I ran into is that the Treal 16T/19T portal gears do not fit in the stock Capra housing. I used my Dremel with a 1/4" sanding drum to remove the bulk of the material, then I wrapped some sandpaper around a 1/2" drill bit to finish it up. I was a bit uncomfortable with the amount of material I had to remove, but it has holding up so far; you have to really cut into two of the screw bosses for mounting the portal cover.
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I had to do a lot of 3D printing to get everything to work the way I wanted, including the links. I did 1/4" diameter for the uppers, and 5/16" diameter for the lowers. My front lowers are 3.850" eye-eye, front uppers are 3.800" eye-eye, rear lowers 6.500" eye-eye, rear uppers 6.125" eye-eye. Total wheelbase is now a little shorter at 12.875". The forward offset transmission/link mounting necessitated the new 129-179mm Injora steel driveshaft for the rear. I decided to cut down one of the stock AX10 driveshafts for the front since they were already shorter than the 119-159mm Injora driveshaft I was running in the rear previously.
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I also printed new 1.9 and 2.2 3 piece wheels to get my outside tire width back down to something reasonable; about 10.75" with the wider 2.2 setup vs. over 11" before.
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Here are the rest of the parts I designed and printed:
Rear shock towers
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Upper link riser for the Capra axle to get the geometry right to minimize pinion roll through travel
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Boatsides for battery and ESC mounting
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Belly plate that keeps the rod ends flush with the bottom and has a recess for the transmission to drop it as low as possible. My belly plate is 3.25" wide, which is about as narrow as I could get it and have clearance between the front upper links and the driveshaft and motor.
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I moved my front shocks up on top of the front axle and mounted vertically when viewed from the side, but tipped in like a real rig when viewed from the front. This required me to mount the shocks 90º relative to how you normally see shocks mounted in RCs. This gave way more room for steering, even with the new wheels that sucked the tires in over 1/4"per side.
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The lower shock mounts/electronics mounting plate to compliment the upper shock mounts. You can also see the new lower spring cups I printed for the shocks since I lost one of the original ones. These new cups allow for slightly more compression travel since they do not take up any space between the lower rod end and the shock body. I really wanted to put my ESC on this plate, but there just wasn't quite enough clearance through suspension travel, so it is only my receiver and on button for the ESC. The ESC ended up getting mounted in the driver side boat side and the battery in the passenger side boat side.
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I also printed a slightly beefier servo mount and raised the upper link mounting position to help squat the chassis under power. I really wanted to mount the servo behind the front axle, but was having a tough time figuring out how to do it, so it is pretty similar to what I used to have.
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An overall of the new chassis:
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With the forward mounted transmission and brass knuckles, I ditched the water from my 2.2 setup and put the stock foams that came with the 1.9 J-Concepts Ruptures in my Moabs since I had the Crawler innovation foams for the Ruptures now. Total weight ended up at 5.34 Lbs. (2,421g) with a 60.8% forward bias.
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How the body looked trimmed to match the angle of the belly and the boatsides:
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I pretty much pulled an all-nighter to finish building my rig in time for the competition, and it still wasn't fully assembled when I had to get it into tech before it closed. I managed to get it finished just before the 1.9 courses started at 9:00am and literally had zero wheel time before the competition. They did the 1.9 trail class from 9:00am-12:30pm, and the 2.2 trail class from 1:00pm to 5:00pm. Each class had 5 courses open simultaneously and everyone could run them at their own pace in whatever order they wanted which was pretty cool and a good way to run everyone through pretty efficiently.

I drove it around for a minute or two before hitting my first 1.9 course, which happened to be one of the easiest of the day and was a real confidence booster. I ran the entire course clean including bonuses with the exception of one rollover I couldn't drive out of.
The second 1.9 course I ran was the hardest and got down to business in a hurry. The second gate was an off-camber 90º turn right on the edge of a 8-10' cliff. I watched the guy in front of me go off the cliff and break his rig. In hindsight, I should have just taken the gate on it since I used several reverses and ended up going off the cliff. To my surprise, none of my 3D printed parts broke and I drove it back on its wheels, but couldn't find a way to get back on course and had to take a reposition. I didn't do too terribly on the rest of the course, but I was running out of time at that point and had to skip the bonuses and ended up timing out right after gate 8 or 9.
The third course I hit was probably the second easiest, but I made a couple of dumb mistakes that cost me points. I did make all the bonuses and gates though within time.
The fourth course I did, I had a really clean run until a bonus towards the end that I got totally screwed up on and in hindsight should have skipped. There was another bonus on that course I made the right call to skip that I never saw anyone make it through clean.
The final 1.9 course I did was the second hardest. I screwed up on a bonus early on in the course and wasted way too much time on it (I ran it clean later in the day). Then there was a drop off that was almost pure luck to not roll into the gate on that I hit a cone on. I think I was one of the only people to clear the 8th gate clean though which made me feel pretty good. I ended up timing out right at the 9th gate, but if I hadn't royally screwed up on that bonus early on, I could have had a pretty good run.

Here are the 1.9 Trail Class results, I got 22 out of 28 which isn't great, but not too bad considering I had zero wheel time with the new setup:
1. Christian -223
2. Nick -209
3. Eric -203
4. Garret -202
5. Zack M. -191
6. Daniel -157
7. Orlando -151
8. Thomas -133
9. Elijah -131
10. Kevin -129
11. Jackson -128
12. Zak S. -122
13. Aaron -120
14. Bacon -102
15. Ryan -101
16. Kaden -89
17. Kenny -84
18. Rona -74
19. Bethel -71
20. Andrew -52
21. Mike -50
22. Me -42
23. Marcy -39
24. Jesse -20
25. Brandon +6
26. Jason +49
27. Rich +84
28. Kailey +89

For the 2.2 competition, all I did was bolt up the Moabs in place of the Ruptures. At this point I had gained some confidence and was starting to get a feel for the rig. On the first course I ran, I watched the two guys in front of me absolutely ruin their runs on the third gate, and even suggested to one of them to take the line through it I ended up running clean, but neither of them did. I ended up running the course pretty clean, but I don't remember if there were bonuses I skipped.
The second course I did, I thought I was totally screwed on, but I ended up doing fairly well aside from the two bonuses I skipped; one was a nasty drop that had a really high chance of putting you on your lid, and the other was a really steep slab climb I couldn't make it up playing around afterwards.
The third course I ran, I did pretty clean, I just skipped one bonus that I couldn't make messing around on after my run, so a good call there.
The fourth course was one of my best runs. I did the whole thing clean except one bonus I skipped that was a real run killer. It was tricky and on the edge of a cliff, but I put tires on it, but backed off when I decided the risk wasn't worth the reward.
The fifth course I ran was really cool and I had a good run going until I screwed up on a gate that really wasn't that hard and cost myself a ton of time and points. I skipped a bonus drop that was mostly luck as to whether you stayed on your wheels or fell off a cliff. I was slaying the rest of the course, but clipped a cone that was totally avoidable trying to rush, and ended up timing out just before the last bonus and gate which I could have made.

I ended up 12th out of 26 which is awesome, and the club president even stopped to tell me that I did really well. It is definitely nice to finally be seeing some progression:
1. Nick -227
2. Ryan -212
3. Kenny -210
4. Christian -208
5. Daniel -204
6. Zack M. -193
7. Garret -191
8. Orlando -142
9. Eric -137
10. Jackson -125
11. Bethel -106
12. Me -97
13. Zak S. -95
14. Thomas -76
15. Aaron -75
16. Bacon -50
17. Kaden -41
18. Iryss -35
19. Brandon +21
20. Elijah +23
21. Mike +57
22. Andrew +59
23. Jesse +78
24. Kailey +119
25. Marcy +141
26. Jason +152

It was an awesome event, and the mad scramble to make it was totally worth it! It was a $50 fee for the whole weekend for all classes and included a T-shirt. The raffle was killer and it seemed like almost everyone won at least something. I ended up with a G-Speed Chassis and a full set of 1.9 KLR/M tires. There were people I talked to that came out from Utah and Colorado which I thought was pretty crazy for an RC event. I am really happy with the improvement in performance and the fact all of the 3D printed parts held together, even after some nasty hits. The Capra rear axle and chassis were huge upgrades.

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1.9 Trail Class Winners:
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2.2 Trail Class Winners:
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Raffle:
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I later got around to printing up some angled rear links to take full advantage of the angle skid and Capra rear axle. I just did a set quick and dirty for the next competition, and while the gain in clearance was massive, I needed to go back to the drawing board and re-do them.

I gave them a 30° angle and transitioned them from 5/16" (same as the straight links I was previously running) to 1/2" at the bend (still 5/16" wide, so a rounded rectangular cross-section) and printed them solid. Even so, they were not as stiff as the straight links and were giving me more axle hop. The angled rod ends I reused from the straight links weren't doing me any favors either. I bent the axle side rod ends which rolled my rear axle up a bit and effectively shortened my wheelbase and let the rear tires get into the body a bit.

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The comp this weekend was the season opener at a local park called "Supper Rock" and we ran one course for each class (Pro, Sporty, 2.2 Trail, and 1.9 Trail) and did some grilling. It was a cold day and it was still right around freezing when we started at 9:00am and the rocks were cold and shaded for the most part. The rock is also partially decomposed granite which is basically like driving on marbles sometimes and can make it really frustrating to get up on top of the rocks.

I had a decent run on the 1.9 course and ended up with a midpack finish. No major mistakes on my part, but I had a rollover, a few reverses, clipped a gate and skipped a bonus.
  1. Christian -50
  2. Garret -47
  3. Aaron -40
  4. Chris -38
  5. Rob -25
  6. ME -21
  7. Thomas -18
  8. Kevin -13
  9. Andrew +26
  10. Rona +26
  11. Stephen +28
The 2.2 course was pretty brutal and only one person finished the course. Me and two other guys couldn't get past gate 4, and everyone else besides the guy who finished got stuck at gate 8 or 9. With the cold weather and this granite, it was amazing how much worse the traction was with the Moabs vs the Ruptures. I know the Moabs are old and outdated, but I had never noticed such a disparity in performance previously. Ultimately traction is what held me back from progressing gate 4. The chassis was settled and stable enough, I just could not get it to hook. In hindsight, I should have just given it a hard bump and taken out the gate, but I don't think I would have made it through gate 5 or 6 in competition. I screwed around a while on course after my run and took me a while to find a line through those points with multiple attempts.

  1. Christian -32
  2. Garret +22
  3. Aaron +24
  4. Andrew +24
  5. Chris +34
  6. ME +34
  7. Stephen +34
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I rolled my car pretty hard several times, both on course and screwing around off course and broke my front shock tower at some point, but didn't realize it until I was home.
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I just printed out another front shock tower to replace the one I broke last time, and redesigned my rear lower links to use 4mm x 30mm studs (3mm x 20mm previously) at the axle end with some SSD 5347 knock-off rod ends that have Axial width balls. I also moved where the bend was in the link to optimize ground clearce and reduced the bend to 25° from 30° in an effort to get it a little stiffer.

Bent 3mm stud from the previous competition:
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The new hardware:
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Much more engagement into the lower link now:
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Showing the difference with the slightly revised lower link design:
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I had another competition. I only ended up finishing one of the three 1.9 courses. Nerves got my on the first course and I hit several gates and pointed out on the 9th gate. The second course was giving everyone hell and I pointed out on the 7th gate. I think only one or two people completed it. The third course was much easier and I did it pretty clean aside from a couple of reverses and a bonus I skipped that I don't know if anyone made.

1.9 Scores:

Christian -105
William -38
Thomas -13 (time)
Scot -13
Mike -1
Me +13
Orlando +23
Steve +41
Zac +89
Rich +92


The first 2.2 course was the hardest of the competition. I ended up pointing/timing out at gate 6 or 7, and only one person was able to complete the course. I did pretty well on the second course, but I was too conservative and skipped all of the bonuses. I could have made one of them no problem after messing around on it afterwards. The third course was easy and I cleaned it and all of the bonuses minus a couple of reverses.

2.2 Scores:

Christian -138
Thomas -55
Mike -37
Orlando -31
Me -15
Steve +14
Jesse +64

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The next competition was the first one I won. Granted, we only ran one course since it was a blizzard, but a win is a win!

We met up in Rio Rancho and it was snow free, but as soon as we started heading out to the comp spot the snow started coming down. It snowed about 3" in the 30 minutes it took everyone to run the one course. We had to sweep the gates so we could see where they were between runs and have a chance of making it through the course. I am not sure if it was my tires or what, but no one else could make it through gate 7, but I completed the entire course with twenty something points. It would have been a super easy course on a dry day. Unfortunately no pictures of my truck.
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After some more recreational runs, I noticed that the M3 set screw on my original front drive shaft was chewing up the original D-style front output on my on my transmission and was getting close to stripping out. Upon disassembly, I found out that the output screws had come loose on the spur gear inside the transmission and it was a good thing I caught everything when I did. I updated the transmission with the later through pin style Axial outputs (AXIC0435) and made sure to use red Loctite when putting it all back together.
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The newer style outputs didn't have a provision for the plastic centering bushing the original outputs had for the spur gear, so I left it out and just did my best to get everything centered before tightening it up. So far so good.
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I decided to weigh the tranny with the Team Brood motor for shits and grins:
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Did a test run to make sure all was good.
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I decided to finally take the plunge and upgrade to an out runner brushless setup and some of the long travel traxxas GTS shocks. I considered the Holmes Mini V3 and Furitek Python X ESCs as well as the Holmes Snubnose Revolver, Team Brood Riot SS, and Furitek Komodo Ten motors, but I ended up going with the Rhino 40A ESC and 2340kV S12 motor which only cost $90 and some change direct from China. The Rhino 40A ESC looks literally identical to the Holmes Mini V3 and uses the same AM32 software for tuning, and is made by DYS who is probably making the ESCs for Holmes as well. The S12 motor is nearly as light as the Holmes team spec Snubnose but the combo was literally half the price. The slow speed crawl has been greatly improved from my HW1080 G1 and 5 slot Team Brood 11T motor and the top end wheel speed is just as good if not a little better; not to mention I have lost a LOT of weight with this new setup. Unfortunately I didn't take any pictures prior to installing in the truck. The new ESC was small enough to mount it to my front axle plate under the upper links. I took this opportunity to redesign my belly plate to mount the transmission ~.1" lower, and raise and narrow the frame rails to give me more clearance over the front axle for shocks and relocating the receiver to make room for the ESC on the axle.

One piece belly plate with integrated boatsides (1st draft, final piece dropped the transmission and motor ~.1" and has walls to help secure the battery)
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Motor after grinding it on some debris that got stuck in the belly plate. You can see the recess in the belly plate for the lowered motor/trans combo in the second picture.
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The Rhino ESC and its mounting location. Yes the lower link is bent and it's time to upgrade the front links to M4 studs as well.
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Relocated receiver:
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The long travel Traxxas GTS shocks are very close to the same extended length and travel of the original AX10 shocks I had been running, but have aluminum bodies, threaded preload adjusters, and metal rod ends with much more misalignment than the slopped-out plastic ones in the Axial shocks. I bought these as take-offs with a .92 Lbs/in springs which were way too stiff for my application, but fortunately I had some of the spring options I had bought from Acxess Spring for my AX10 shocks that fit the GTS shocks well. I used part number PC032-593-12000-MW-1848-CG-N-IN (.853 Lbs./in) for the front and PC030-578-14800-MW-2350-CG-N-IN (.552 Lbs./in) for the rear. I also took off the hard plastic "bump stops" that ate up a considerable amount of travel.
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Unfortunately, the stiction/friction caused by the seal preload and oil in the GTS take-offs really hindered the performance of the truck in the next competition. The truck didn't really want to flex or settle at ride height, and they were really slow to drop out when I was hung on my belly.

With the raised and narrowed frame rails I updated my shock and body mounts.
Front:
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Rear; I decided to lean the shocks further forward to get more wheel travel, but greatly exacerbated the torque twist:
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New ready to run weight is 2,333.3g or 5.14 Lbs with my 2.2 setup and 2,125.1g or 4.69 Lbs with my 1.9 setup and right at 60% forward bias still.
 
So after the last round of mods, I took the truck to a competition on Cinco De Mayo and the truck was noticeably more stable on side hills. As I mentioned earlier, my suspension was really killing me with how stiff the shocks were, but overall I was happy with the performance of the truck. Definitely the hardest I have beaten on it to date. Plenty of power on tap with the little outrunner.

The first 1.9 course went very well for me. Aside from tagging one gate and a few reverses, I ran the course clean and got all three bonuses. Not a super hard course, but it got the better of quite a few drivers. The second course I really screwed myself on the first gate. The gate itself wasn't too hard, but the approach was tricky and I wasted way too much time trying to get on the right line and had to rush through the rest of the course and skip a bonus I probably could have made, but I literally finished the tenth gate at the last second. The same thing pretty much happened to me on the third course. Again I wasted too much time on the first gate and was racing to get through the tenth gate with seconds to spare, but I at least had time to grab a bonus line. I was a bit anxious and off my game the whole competition, but I am happy to have finished in the top half of the 1.9 field.

1.9 trail class
Garret -109 (4:49 left)
Christian -109 (3:32 left)
Orlando -67
Chris -59
Me -30
Gary +15
Kevin +22
Rona +50
Scot +61
Rich +92
Ed +136

For the 2.2 courses my best run was probably the first course even though I took a reposition on the first gate after falling of a ledge I couldn't get back up and only made it to the 8th gate before timing out. As bad as that sounds, I did it the third best. The second course I did alright on but ended up timing out on the 9th gate. I really need to work on my time management; 6 minutes seems to fly by when you're the one driving. I was on track for good finish on the third course, but got wrapped up in a grassy bush after dropping through the 8th gate and ended up popping the original plastic front drive shaft apart trying to break free. I definitely could have done better on the 2.2 courses.

2.2 trail class
Garret -96
Christian -54
Orlando +41
Greg +43
Chris +67
Me +70
Scot +94

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One of the other guys out there shared some good pictures with me actually in them.
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This one is me running and driving at full throttle to make the last gate on the second 1.9 course.
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The driveshaft after I popped it back together at home. it is permanently twisted, but still useable as a spare. I picked up a metal 68-86mm Injora driveshaft to match my rear drive shaft.
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After almost a year, I broke one of my printed wheels.
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I am not sure exactly when it happened, but I noticed it rubbing on my drag link rod end one day. There were several improvements I was wanting to make to my printed wheels, but between the design and print time I looked into wheels I could buy since I really didn't want to put in the time and wasn't completely satisfied with my printed PLA wheels. I liked the Dlux high-clearance wheels, but for ~$60/pair I couldn't justify it. I found some similar high clearance wheels on Amazon made by "AMK" that nearly matched all of the Dlux wheel specs for $50/set for 2.2" wheels and $40/set for 1.9" wheels and went ahead and ordered both. I am extremely pleased with them. The offset is perfect (they utilize separate hubs, so it is adjustable if I wanted to), they have tons of clearance for bigger knuckle weights, they are well-vented, and the 2.2" wheels are lighter than my printed wheels.
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I found out that 90% of the stiction issues I was having with the GTS shocks was the seal pack preload. After reading an article from Traxxas themselves about tuning GTS shocks for crawling, I found out that if you leave the seal cap loose 1/2 to 1 turn, the shocks operate much more smoothly.
 
The 1.9 versions of the AMK wheels ended up being slightly heavier than my 3D printed ones, but the offset was perfect like the 2.2 versions and they have a ton of clearance for a 1.9 wheel.
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I also went ahead an put the red pistons and smaller seal spacers in my GTS shocks that were mentioned in the Traxxas tech article and that made a HUGE difference. I also printed small spacers to be able to torque the seal caps tight, but keep them one turn "loose" on the seals. No leaks so far.
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New thinner seal spacers:
img_8669-jpeg.911648


Old stock seal spacer:
img_8670-jpeg.911650


New red piston:
img_8671-jpeg.911651


Original piston:
img_8672-jpeg.911652


I also bought a Losi Racing shock oil kit (TLR74020) and refilled them with the blue 20wt oil. Now they are nice and smooth and work great.
 
I went to another competition and the truck did well. Mid-pack finish in 1.9, and I started out with the best score on the first 2.2 course, but I stripped my spur gear at the 7th gate on the second course and got a DNF. I had the Protek 12t pinion meshed too deep on the spur, so the gears were meshed pretty loose despite the lash being set appropriately. I cleaned the teeth up on the spur a bit and meshed the gears really tight and was able to make a clean run on the third 2.2 course up until gate 8 when I rolled in a bush and finished off my spur trying to drive it out.

Scores:

1.9 trailclass
Garret -43, -42, -29 = -114
Christian -47, -37, +24 = -50
Andrew +3, -15, -5 = -17
Mike +9, +13, -17 = +5
Me -11, -1, +22 = +10
Kevin -29, +22, +30 = +23
Stephen -17, +28, +24 = +35
Rich -9, +34, +38 = +63
Rona +10, +30, +24 = +64
Jesse +22, +30, +36 = +88

2.2 trailclass
Christian -7, -33, -35 = -75
Garret -5, -22, -32 = -59
Andrew +18, +24, -30 = +12
Me -16, +28, +24 = +36
Stephen +34, +19, -7 = +48
Mike +32, +32, -14 = +50
Jesse +30, +30, +26 = +86

img_8674-jpeg.911661
 
After killing my spur gear in the last comp, I went to the 93T spur gear I used to run and a 10T Robinson Racing pinion (RRP1410). I also switched over to Tattu R-Line 4S 650 batteries to keep the same top end, drop some weight, and be able to mount the battery to the front axle. Since I started building a separate 1.9 class truck, I also ordered some freshly released 5.25" JConcepts Ruptures (4100-02) along with some Crawler Innovations foams with the high density inners (CWR-1350 & CWR-1351) and stretched my rear links to get my wheelbase just over 13.125". I also added the "light" Injora brass portal covers to help get my COG lower. It all ended up with a total weight of 5.01 Lbs and a 59% forward weight bias. I had to hack away a bit more on the body to clear the bigger tires, but it still looks reasonable.
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Crappy picture, but the new battery and ESC mount on the front axle.
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Shortly afterwards, we had the NMRCC State Championship in the Rio Puerco area west of Albuquerque. Not quite as big as the State championship in 2023, but still a pretty good turnout. I only attended Saturday when they were running the 1.9 and 2.2 trail classes and Super in the evening, but they ran Sporty, Pro, and Mini on Sunday.

Trail class rigs.
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img_8785-jpg.917366

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Trying to scrub my new tires in before the 2.2 class started.
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The truck performed great aside from the motor/esc getting hot and glitchy a few times (90°+F and no shade all day). Course 1 was a bummer because I completed gates 1 through 9 and all 3 bonuses without a single penalty, but I got screwed up going into gate 10 and couldn't get through it before timing out, so I went from a perfect run (-50) to +22 which was my only positive score of the day. Course 3 I screwed up my run hitting both cones on gate 10 being dumb and was completely avoidable. I ended up in 8th place, but if I had finished course 1 and not botched gate 10 on course three I might have been able to snag 6th or 7th place.
img_8795-jpg.917385
 
There was one 2.2 course for the season opener an I managed to snag first or second. Then I had another competition recently and it was a tough one. I only finished one course. One course was so tough, only two people managed to complete it (the top two finishers), and only four people completed the other course I didn't finish (the top four finishers).

2.2 Trailclass
1. Christian -29, -24, -18 = -71
2. Garret -20, -23, -16 = -59
3. Thomas -17, +22, -22 = -17
4. Stephen -17, +26, -4 = +5
5. Brian -11, +22, +28 = +39
6. Me -16, +28, +28 = +40
7. Chris S. +1, +26, +26 = +53
8. Sunshine -2, +34, +28 = +60
9. Mike H. +3, +30, +28 = +61
10. Jesse +24, +32, +28 = +84
11. Orlando +50, +28, +30 = +108
12. Anthony +32, +28, +50 = +110
13. William +50, +26, +50 = +126
14. Zak +50, +28, +50 = +128

9TQZCSP.jpeg


NMRCC got a new president and VP this season and they decided to ban Ruptures from the trail class despite them being run in the trail class for several years now. Now I need to find some new tires which pissed me off a bit since I just bought the Ruptures for this build and I was running Ruptures on my 1.9 build as well. Oh well, I want to pick up some of the 5.25" Tusks, but they are out of stock everywhere.

Current NMRCC Trail Class rules for anyone that is interested:

2025/2026 Trail Class Rules
They do apply for both classes (1.9 and 2.2) unless specified:
Any rule with asterisks is new
Chassis:
- Chassis rail length must be as long as the wheelbase (adding parts to the chassis to make it longer isn't allowed)**
- Chassis can be any regular rail (metal or carbon fiber), stock rail, stock tube, custom tube, and TVP (twin vertical plate).
Vehicle weight/ Added weight:
- Knuckle weights ARE allowed. Weighted wheels are allowed.
Body:
- Bug bodies ARE allowed
- Bodies must be scale in appearance.
- Tube frame chassis must have a minimum of at least a roof, hood, and sidepanels.
- Hardbodies are allowed.
- NO competition style bodies such as Lattice Innovation bodies, or 1/16 and smaller bodies
Tires:
- Scale tires only.
- NO competition or pin tires allowed.
- Tires can be siped, grooved and trimmed.
- Cut and shut tires are allowed, but as for the 1.9 class, only narrowing is allowed (no sidewall modifications)**
--BANNED TIRE LIST--
ALL Pin style tires are not allowed (For example: Reefs RC Cheater tires or Ibex)**
Sedonas
Rovers
Dlux Goats**
JConcepts Ruptures**
Extreme Route Lampreys**
Losi boss claws
Chisels
Panthers (all types)
Wheels:
- Wheels must be either 2.2" or 1.9", no other sizes. They will be ran with the corresponding tire, and ran in the corresponding class.
Electronics:
- One motor limit
- No 4WS or Dig is allowed.
 
Great little thread going on here. Love reading about the changes and the effects therof. Keep it coming good sir!
Likewise, I read through al those posts and marvelled at all the painstaking troubleshooting that took place!

And it was great seeing an old original Axial get put through its paces alongside more modern rigs...;)(y)
 
Great little thread going on here. Love reading about the changes and the effects therof. Keep it coming good sir!

Likewise, I read through al those posts and marvelled at all the painstaking troubleshooting that took place!

And it was great seeing an old original Axial get put through its paces alongside more modern rigs...;)(y)

Thanks guys! The only AX10 parts left at this point are the body, front axle, and transmission. I am getting ready to swap out the transmission and front axle, so all that will be left at that point will be the body. I'll probably start a new thread at that point, but its got at least one more competition in store for it.

I'll probably take all the AX10 parts and the SCX10 frame and throw together a rig with the old HPI Bronco body and either give it to my father or sell it all for pennies on the dollar. Honestly, the AX10 axles with the XR10 mod and the 3 gear transmission are still viable in today's comp scene; although there are better options now.
 
This is a sweet build, I'm glad to see the Scorpion getting some more love. I'm definitely going to take some notes for my own build, although I plan on trying to keep the original chassis. Nice rig man, excited to see where it goes from here.
 
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