Project: Axial XR10 Rock Crawler

When I first heard I was attending the Axial West Coast Crawling Championships, I was both excited and a little intimidated. Excited because this would be my first crawling event and I’ve always wanted to try it. Intimidated because this was my first crawling event and I had NO idea what to expect. For the event, Axial was kind enough to supply one of their killer XR10 rigs along with a slew of their aftermarket goodies. First off, I want to say that the XR10 is an excellent crawling vehicle. In stock form, it is capable of winning events and durable enough to survive some pretty amazing crashes. I should know. I did, however, install all of the aftermarket parts they included and, not only did I notice a slight weight advantage, but it also helped out the XR10’s performance. Let’s dive into some details!

CHASSIS & SUSPENSION
The stock, black-anodized aluminum chassis and electronics mounting plate are definitely high-end pieces, but I opted for Axial’s aftermarket carbon parts for strength and weight savings. While all the parts are pretty well keyed together, in a long distance fall there is the possibility that the aluminum might bend and you might not even know it. The carbon pieces resist this bending and, actually, look pretty trick! In addition to the chassis side plates and electronics mount, I also used Axial’s carbon battery mount. This piece does the same thing as the stock plastic part but it is super-cool carbon fiber! Moving to the front suspension, I replaced the stock, plastic C-hubs and steering knuckles with Axial’s aluminum parts. A slick, carbon fiber servo tray and hi-leverage steering arm round out the upgrades. Towards the rear, I kept things simple and swapped out the rear, plastic axle lockouts with Axial’s upgraded aluminum ones. These eliminate any flexing that may occur at the tire. Finally, I replaced all eight of the chassis links with Axial’s heavy duty, high-clearance links set. These might have added a tiny bit of weight, but they really help the XR10 slide off or over any rocks they come in contact with.

DRIVETRAIN
Both of the XR10’s gearboxes are solid as a rock and can take quite a bit of punishment, but there are a couple pieces you can drop in to make it even better. I started by swapping out the heavy, stock idler and final gear for Axial’s machined, lightweight units. Also replaced were the gearboxes ‘Gear 1’ and ‘Gear 2’ for lighter, machined parts. Altogether, these pieces dramatically reduce the rotating mass in each gearbox, allowing quicker, controllable acceleration up and over obstacles. To finish off the drivetrain, I upgraded each gearbox with one of Axial’s heavy duty gear plates. These plates include new, recessed bearings and help dissipate motor heat.

ELECTRONICS
Since the XR10 is a MOA (Motor On Axle) design, I basically needed two of everything in the ‘go’ department. I loaded up the XR10 with a pair of Tekin’s FXR ESCs and 35-turn, Heavy Duty brushed motors from their Crawler Series. This combo is programmable and allows you to complete control of the ESC’s setup. From the ESC (or Tekin’s awesome HotWire programmable system), you can fine tune each ESC to be exactly the same or completely different. I was able to program them in sync to allow me precise control at any throttle position, in forward or reverse. For steering duties, I knew I wanted a servo with some serious power and a complete metal geartrain. The Futaba BLS152 servo fit that bill, with impressive specs of .014 transit speed (at 6V) and a torque rating of 431 oz! Mated with a metal servo horn, this uber-powerful servo was able to turn the wheels no matter what situation I got the XR10 into! It’s a bit on the hefty side, but that weight is low and to the nose of the chassis so it actually worked out well. To make sure everything had enough power, I installed a Castle 10A BEC. Not once did I detect any hint of power loss in either the steering or the throttle. And speaking of power, a tiny MaxAmps 3S 2250 LiPo was snuggly mounted within the chassis rails of the XR10. This pack was awesome and worked flawlessly over the three days I abused it. In fact, it never left the interior of my XR10! And finally, to control my crawler on all of the rocks and hillsides, I opted for Futaba’s 4PL radio system. Small and lightweight, this radio system has an amazing feature list that is perfect for crawling. In addition to all of its normal features (which most radios have), the 4PL’s mixing feature allows you to mix 4WS (4 Wheel Steering) or a special section for dual ESC’s. This, along with its 2.4GHz, alarms, 128×64 dot backlit LCD and whopping 40-model memory make this radio a super deal, especially if you’re a serious crawler!

BODY, WHEELS & TIRES
The body on my XR10 is their sharp looking Hardline body. Sexy and sleek, this body is by far one of the best I’ve seen on a crawler! I sent mine to Larry over at Kustom RC Graphics and he laid down my new 2011 paint scheme. It flows wonderfully on this body and looks killer on the rocks! The stock VWS wheels were retained as were the orange aluminum rock rings. I installed a full set of Vanquish Products SST Weights in both front wheels, and replaced the stock plastic VWS beadlock wheel weight locks with Axial’s aftermarket carbon fiber ones. Even though the rear wheels did not have weights in them, I installed the carbon wheel weight locks anyway to keep the look the same. Wrapping all four wheels is a set of Hot Bodies Sedona crawler tires in the soft, white compound.

COMPONENTS
Axial Racing
axialracing.com
• XR10, #AX90017
• Stage 1 Aluminum Upgrade Kit, #AX30432
• Stage 2 Carbon Fiber Upgrade Kit, #AX30433
• Stage 3 Aluminum Hi-Clearance Links Kit, #AX30434
• Carbon Fiber Electronics Plate, #AX30772
• Carbon Fiber Battery Plate, #AX30774
• Heavy Duty Gear Plate, #AX30787
• High Leverage Steering Arm, #AX30788
• Machined 22T-48P Final Drive Gear, #AX30767
• Machined Lightweight 36T-48P Final Gear, #AX30768
• Machined Lightweight 36T-48P Idler Gear, #AX30770
• Machined 12T-48P Gear 1,#AX30769
• Machined 12T-48P Gear 2, #AX30771
• Aluminum Shock Cap, #AX30111
• 2.2 VWS Carbon Fiber Wheel Weight Locks, #AX30757

Futaba
futaba-rc.com
• BLS152 Super High-Torque Air Servo, #FUTM0512
• 4PL Transmitter System, #FUTK1400

Tekin
teamtekin.com
• FXR + T35 HD Combo, #TT2109 (x2)

MaxAmps
maxamps.com
• LiPo 2250 3S 11.1V Battery Pack

Hot Bodies
hbracing.com
• HB Sedona Tire – White Compound, #67918

Vanquish Products
vanquishproducts.com
• VP .6 Caliber SST Wheel Weight Set, #VPS01065

Castle Creations
castlecreations.com
• CC BEC, #010-0004-00

THE DRIVE
When I take any vehicle out for a day of play, practice or racing, I always try to get around the track as fast as possible. This usually means quite a few practice laps at speed to find the best line, maybe change the setup, tires, gearing, etc. By main event time, things usually go pretty good and I feel confident with my run. With crawling, it’s not quite the same deal. You still have to run the course in the least amount of time possible and the gates are just slightly wider than your crawler, so precision driving is a must! The catch is that you only get ONE trip through the course; no one or two-hour long practice session where you can test and tune. It’s show up, put your rig on the rock and go for it. Since this was my first crawling event, I was already a bit overwhelmed at the notion that I was going to put my XR10 down and have it fall off the side of every rock and hill I came to. I have to say, though, I was completely surprised at how well this thing sticks! The low CG of the XR10 coupled with the grippy Sedona tires was enough to perform some incredible side-hill action! Throttle control is key, and light inputs on the Futaba 4PL had me climbing and clawing my way from gate to gate in no time. Using the Dual ESC mixing mode, I could set up my electronic front and rear dig to help me navigate some of the harder sections I thought were not possible, especially for me. Even the articulation of the XR10 is amazing and really cool to see. When I needed a bit more boost, a quick blip of the throttle sent mega-juice from the 3S MaxAmps pack to the twin Tekin power-plants and away I went. The high-clearance aluminum links worked perfect, and allowed me to climb over larger sections of rocky terrain without any hang ups. Thanks to the added aluminum and carbon fiber, the XR10 required zero repairs on course, even after some horrendous falls right down onto the rocks below. Just check out the battle scars on the body.

FINAL THOUGHTS
I was always interested in crawling but never had a vehicle to do it with. My XR10, with all its included goodies, is probably a bit overkill for the seasoned driver, but for me it was all about performance and durability. I’m positive all these upgrades gave me and my rig a definite advantage and, now that I have an event under my belt, I’ll feel more confident up on the rocks. Plus, it just looks cool. Enjoy!