Every basher hits the same wall eventually. The 1/10 truck that felt fast now feels small, the skatepark gaps look bigger than the truck, and somebody at the field shows up with something that weighs as much as a bowling ball and launches like it owes the ground money. That is 8S territory, and in this class three trucks come up again and again on our repair bench and at the counter: the Traxxas X-Maxx, the ARRMA Kraton 8S EXB and the ARRMA Outcast 8S EXB.
They all run two 4S LiPo packs, they all claim 50+ mph, and they all cost real money once you add batteries and a charger. So the right pick is less about which one wins a spec sheet and more about where you drive and how you crash. Below is what each manufacturer says, as of October 2026, plus what that means in your backyard, at the BMX track and on the bench afterward.
The Short Answer
Buy the X-Maxx if you drive tall grass, rough fields and big terrain and want the most ground clearance; buy the Kraton 8S EXB if you want a long, stable speed monster truck for big jumps and fast runs; buy the Outcast 8S EXB if your idea of fun is wheelies, flips and skatepark stunts.
- Size: all three are about 28 to 31 inches long; the X-Maxx is the tallest and narrowest, the ARRMAs are lower and wider.
- Power: all three are 8S trucks running two 4S packs; the ARRMAs are also rated for 6S (two 3S).
- Speed: each maker claims 50+ mph. Traxxas specifies two 4S packs and an optional pinion; ARRMA lists no conditions.
- Budget for batteries: two 4S packs and a dual charger are part of the purchase, not an extra.
1. The Spec Sheet Showdown
Here is how the three line up using the numbers each manufacturer publishes: the Traxxas X-Maxx 77096-4 page, ARRMA's Kraton 8S EXB page and its Outcast 8S EXB page. ARRMA does not publish a weight for either truck, so we left that blank instead of guessing.
| Spec (manufacturer) | Traxxas X-Maxx 8S (77096-4) | ARRMA Kraton 8S EXB (ARA5808V2T1) | ARRMA Outcast 8S EXB (ARA5810V2T1) |
|---|---|---|---|
| Type | Monster truck | 1/5 speed monster truck | 1/5 stunt truck |
| Length | 30.67 in (779 mm) | 30.35 in (771 mm) | 28.11 in (714 mm) |
| Width | 21.3 in (540 mm) | 23.7 in (602 mm) | 23.43 in (595 mm) |
| Height | 13.99 in (355 mm) | 11.1 in (282 mm) | 12.01 in (305 mm) |
| Wheelbase | 18.92 in (480 mm) | 19.33 in (491 mm) | 16.93 in (430 mm) |
| Ground clearance | 4.2 in (107 mm) | 2.56 in (65 mm) | 2.56 in (65 mm) |
| Weight | 19.1 lb (8.66 kg) | Not listed by ARRMA | Not listed by ARRMA |
| Motor | Velineon 1200XL, 1275Kv, 48 mm diameter | Spektrum FIRMA 5687, 1100Kv, 4-pole | Spektrum FIRMA 5687, 1100Kv, 4-pole |
| ESC | Velineon VXL-8s | Spektrum FIRMA 160A V2 Smart | Spektrum FIRMA 160A V2 Smart |
| Steering servo | Traxxas 2085X metal gear, waterproof | Spektrum S6510 steel gear (820 oz-in at 8.4V) | Spektrum S6510 steel gear (820 oz-in at 8.4V) |
| Batteries needed | Two 4S LiPo, Traxxas High-Current connectors | 6S or 8S: two 3S or two 4S LiPo, IC5/EC5 | 6S or 8S: two 3S or two 4S LiPo, IC5/EC5 |
| Tires | Belted Sledgehammer, 8 in tall | dBoots Copperhead 2 Big Block | dBoots Back-Flip Big Block |
| Radio | Traxxas TQi 2.4GHz, 2-channel | Spektrum DX3 with SR6200A AVC receiver | Spektrum DX3 with SR6200A AVC receiver |
| Top speed claim | "50+ mph with two 4s LiPo batteries and optional pinion gear" | "50+" (no battery or gearing conditions given) | "50+" (no battery or gearing conditions given) |
Two ARRMAs, one platform
The Kraton and Outcast are siblings. Both use a 5 mm 7075-T6 aluminum chassis plate, 20 mm bore oil shocks with 6 mm shafts, a Spektrum FIRMA 5687 1100Kv motor, the FIRMA 160A V2 Smart ESC and the same 9.06 internal gear ratio. RC Car Action covered the Kraton 8S EXB RTR when ARRMA announced it in July 2023, with the same motor and ESC listed. The differences are where the fun lives: the Kraton's wheelbase is 491 mm against the Outcast's 430 mm, and they wear different tires and bodies.
The X-Maxx plays a different game
Traxxas went tall. The X-Maxx stands 13.99 inches high with 4.2 inches of center ground clearance, against 2.56 inches on both ARRMAs. It rides on 8-inch belted Sledgehammer tires, uses a Velineon 1200XL motor rated at 1275Kv and a VXL-8s ESC, and sends power through a Cush Drive system plus a Torque-Biasing Center Drive that Traxxas says absorbs shocks to improve driveline durability. At 19.1 pounds, it is a lot of truck to catch when it cartwheels.
Reading the speed claims
Every one of these trucks advertises 50+ mph, and none of those numbers is a promise about your driveway. Traxxas is specific: "50+ mph with two 4s LiPo batteries and optional pinion gear," so the out-of-the-box gearing is not the setup behind the headline. ARRMA's spec pages list top speed as "50+" without saying which battery or pinion was used, and the Horizon Hobby listing files the trucks under its 50+ mph category. Treat all three as the manufacturer's claim under ideal conditions with full 8S packs. On grass, on 6S or with stock gearing, expect less. On paper the X-Maxx motor has the higher Kv (1275 vs 1100), but final gearing, tires and weight decide real speed, not Kv alone.
2. Which One Fits How You Drive
Forget the spec sheet for a minute and picture your most common run. The answer usually falls out of that.
Pick the X-Maxx for rough ground and tall grass
If you drive pastures, construction-site dirt piles (with permission) or a backyard that has not seen a mower in a while, ground clearance is everything. The X-Maxx's 4.2 inches and tall tires let it roll over stuff that beaches lower trucks. The flip side is basic physics: it is taller and narrower than the ARRMAs (21.3 vs about 23.5 inches wide), and a tall, narrow truck is quicker to traction-roll in hard, fast turns on grippy pavement. Drive it like a monster truck and it rewards you.
Pick the Kraton 8S for speed runs and big air
The Kraton is the long, wide, low one. ARRMA calls it a speed monster truck, and the 491 mm wheelbase is what keeps it straight at speed and level in the air. It is the one we steer people toward for big ramps, open lots and long straight runs. With Copperhead 2 tires it bites on dirt and asphalt alike. The trade-off is that 2.56 inches of clearance, which shows up in tall grass and deep ruts.
Pick the Outcast 8S for stunts and skateparks
Same guts as the Kraton, but 61 mm less wheelbase. Shorter means it rotates faster: easier wheelies, quicker backflips and a truck that wants to be thrown around. ARRMA fits Back-Flip tires and calls it a stunt truck for a reason. If you drive bowls, curbs and dirt jumps where you land at odd angles, the Outcast is the more playful choice. If you want calm stability at speed, it is the wrong one. Not sure where the line is between a stunt truck and a monster truck? Our RC classes explainer breaks it down.
A few things all three share
All three need a big, open space. At 28 to 31 inches long and 50+ mph claimed, none of these belongs in a cul-de-sac with kids and parked cars. They are also hard on parts in the places you would expect: suspension arms, bumpers and drivetrain take the hits on landings. ARRMA's EXB trucks ship with aluminum chassis and brace parts already installed, and Traxxas built the X-Maxx's all-metal driveline around 8S power. Either way, keep spares for arms and bumpers in your bag.
3. Batteries, Charging and the Real Cost of 8S
None of these trucks comes with batteries or a charger. That is the part of the budget people forget, and it is also the part that keeps you safe. Before your first 8S charge, read our RC battery and charging guide.
What each truck needs
X-Maxx: two 4S LiPo packs with Traxxas High-Current connectors. Traxxas specifies two 4S packs (8S) for this model and recommends its 4S 6700mAh iD pack. Kraton and Outcast: ARRMA rates both for 6S or 8S and calls for two 3S or two 4S LiPo packs with IC5 or EC5 connectors. Two 4S packs at 3.7V nominal per cell add up to 29.6V nominal and 33.6V fully charged.
Learn on 6S first (ARRMA only)
Because the Kraton and Outcast are rated for 6S, a pair of 3S packs is a gentler way to get to know a truck this heavy. Learn the throttle and the landings, then move to 8S once the truck stops surprising you. For the X-Maxx, stick to Traxxas' spec of two 4S packs. If you are stepping up from a 2S or 3S truck, our brushless and cell-count upgrade path shows how the jump in voltage changes things.
Safe 8S charging, step by step
- Charge each 4S pack on its own channel. Your truck wires the two packs in series to make 8S. Your charger should not. A dual charger handles both packs at once, each with its own balance.
- Use the system the truck was designed around. X-Maxx wants Traxxas High-Current connectors (Traxxas recommends its 4S 6700mAh iD pack, part 2890X). The ARRMAs use IC5, which Spektrum Smart chargers read directly.
- Charge on a non-flammable surface and stay in the room. Two big 4S packs hold a lot of energy. Never charge in the truck, in a hot car or unattended.
- Let packs cool before charging. After a hard 8S session, packs come off warm. Give them time to come back to room temperature.
- Store at storage voltage. Spektrum Smart G2 packs drop themselves to 3.90V per cell after 72 hours of sitting; for other packs, use your charger's storage mode if they will sit for more than a few days.
- Retire puffy packs. A swollen LiPo is done. Do not charge it, do not run it.
Gearing and heat
Traxxas' speed claim depends on an optional pinion, and bigger pinions mean more load and more heat in the motor and ESC. If you chase the number, gear up in small steps and check motor temperature after short runs. Our gear mesh and gearing guide covers how to set mesh and change pinions without chewing a spur.
Conclusion
There is no bad truck in this group, only a bad match. If your driving is rough terrain and tall grass, the X-Maxx's clearance and size make sense. If it is big jumps and fast passes across open ground, the Kraton 8S EXB's long wheelbase is the stable pick. If you want to backflip off a skatepark bowl, the Outcast 8S EXB was built for that. Whatever you choose, budget for two 4S packs and a proper dual charger, and treat the 50+ mph claims as a ceiling, not a guarantee.
Want to see how big these trucks are in person, or talk through batteries and spares before you buy? Stop by our Cumming showroom or browse our 1/5, 1/6 and 1/8 scale trucks, the ARRMA collection and the Traxxas collection. Questions? Contact the shop.
Gear Mentioned in This Guide
Traxxas X-Maxx 8S Belted (77096-4)
The tallest of the three: 4.2 in of ground clearance, 8-inch belted Sledgehammer tires and Traxxas' 8S power system.
Shop now
ARRMA Kraton 8S EXB RTR (ARA5808V2T1)
Long 491 mm wheelbase speed monster truck with EXB aluminum parts and a FIRMA 160A V2 Smart ESC.
Shop now
ARRMA Outcast 8S EXB RTR (ARA5810V2T1)
Same EXB chassis and electronics as the Kraton on a shorter 430 mm wheelbase built for flips and wheelies.
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Traxxas Dual 4S LiPo Completer with EZ-Peak Live Dual (2997)
Two 4S 6700mAh iD packs plus a dual iD charger: the matched 8S setup for an X-Maxx.
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Spektrum Smart G2 PowerStage 8S Bundle (SPMXPSS850)
Two 4S 5000mAh Smart G2 IC5 packs and an S2100 2x100W charger for the Kraton or Outcast.
Shop nowFrequently Asked Questions
Is the X-Maxx bigger than the Kraton 8S?
Taller, yes; longer and wider, no. Traxxas lists the X-Maxx at 30.67 in long, 21.3 in wide and 13.99 in tall. ARRMA lists the Kraton 8S EXB at 30.35 in long, 23.7 in wide and 11.1 in tall. The X-Maxx also has far more ground clearance: 4.2 in vs 2.56 in.
What is the difference between the Kraton 8S and Outcast 8S?
They share the same EXB chassis, motor, ESC, servo and radio. The Kraton is a speed monster truck with a 491 mm wheelbase and Copperhead 2 tires; the Outcast is a stunt truck with a shorter 430 mm wheelbase and Back-Flip tires, so it flips and wheelies more easily.
How fast is the X-Maxx 8S?
Traxxas claims 50+ mph with two 4S LiPo batteries and an optional pinion gear. That is the manufacturer's claim; with stock gearing, on grass or with tired packs you will see less.
Can I run the Kraton 8S or Outcast 8S on 6S?
Yes. ARRMA rates both trucks for 6S or 8S, using two 3S or two 4S LiPo packs with IC5 or EC5 connectors. 6S is a good way to learn the truck before stepping up to 8S.
What batteries does the X-Maxx need?
Traxxas specifies two 4S LiPo packs with Traxxas High-Current connectors and recommends its 4S 6700mAh iD pack (part 2890X). Traxxas sells a completer pack with two 4S iD packs and an EZ-Peak Live Dual charger.
Do these trucks come with batteries and a charger?
No. All three are ready-to-run with a radio, but batteries and a charger are sold separately. Plan for two packs and a charger that can handle two 4S packs.
