VehiclesHobao Hyper MTX RTR

Hobao Hyper MTX RTR
1/8 scale · monster truck · HB-MTXE-C150BU
- Top speed
- 44mphcalculated
- Final drive
- 21.75:1
- Tire
- 182mm

Specifications
Last modified
| Spec | Value | Basis |
|---|---|---|
| Drivetrain | ||
| Pinion | 15TStock | Stock |
| Spur | 45TStock | Stock |
| Transmission & axle | 7.25:1Derived | Derived |
| Spur ÷ pinion | 3.000:1Calculated | Calculated |
| Final drive | 21.75:1Stock | Stock |
| Wheels & tires | ||
| Tire diameter | 182mmStock | Stock |
| Rollout | 26.3mm per motor turnCalculated | Calculated |
| Wheel hex | 17 mmStock | Stock |
| Power | ||
| Motor | 2000KVStock | Stock |
| Motor shaft | 5 mmStock | Stock |
| Battery | Up to 6SLiPoStock | Stock |
| Stock motor | 1/8 Brushless Motor 4076 2000KVStock | Stock |
| Stock ESC | Hobby Wing 150AStock | Stock |
| Battery connector | XT90Stock | Stock |
| Performance | ||
| Theoretical top speed | 43.5mph on 6SCalculated | Calculated |
| Motor speed | 44,400rpm, no loadCalculated | Calculated |
| Chassis | ||
| Weight | 6.4 kg (14.1 lb)Stock | Stock |
| Length | 635 mm25 inStock | Stock |
| Width | 495 mm19.5 inStock | Stock |
| Height | 290 mm11.4 inStock | Stock |
| Wheelbase | 396 mm15.6 inStock | Stock |
| Diff oil, front | 5KStock | Stock |
| Diff oil, center | 7KStock | Stock |
| Diff oil, rear | 5KStock | Stock |
| Vehicle | ||
| Part number | HB-MTXE-C150BU | |
| Scale | 1/8 | |
| Class | Monster truck | |
Stock is as the vehicle ships. Calculated is worked from the stock figures on this page rather than stored beside them, so the two cannot drift apart. Derived is worked out from gear tooth counts the maker publishes rather than printed as a ratio; the notes below say how. The top speed is kinematic: an ideal no-load RPM with no slip and no loss under load, so a real car is slower.
Gearing parts
| Component | Teeth | Pitch | Bore | Part number |
|---|---|---|---|---|
| Fitted at the factory | ||||
| Pinion | 15T | Mod 1 | 5 mm | 89325 (opens in a new tab) |
| Spur | 45T | Mod 1 | Not applicable | 94089 (opens in a new tab) |
Tooth counts are the ones in the specifications above. Pitch is given as metric module (Mod 1, Mod 0.8) or diametral pitch (32P, 48P). They are different standards and are not interchangeable, even where the numbers look close. Bore is the pinion’s hole, listed separately from the motor shaft (5 mm on the stock motor). Linked part numbers go to the maker's or official distributor's page for that part.
How these numbers were settled
Hobao's page lists a 15T motor gear, a 36T spur and 9T/29T differential gears, but the 36T gear sits on the center differential and is not the gear the pinion drives.
- The manual (steps 39 to 44) and its parts list show the 15T motor gear (89325) driving a 45T spur (94089) on a gear axle, whose 16T gear (94088) turns the 36T center differential gear (94091N).
- The front and rear differentials use a 29T crown gear and a 9T pinion (94001N, 94002N).
- That makes the ratio after the spur 7.25:1 (36/16 x 29/9) and the total 21.75:1, worked out from the tooth counts, since Hobao prints no ratio.
- Hobao's tire drawing gives the tire as 182mm tall and 98mm wide.
- The RTR has a 2000KV four-pole motor with a 5mm shaft and a Hobbywing 150A speed control rated for 4S to 6S, fed by two packs on XT90 plugs.
- The manual fills the front and rear differentials with 5000 silicone oil and the center differential with 7000.
- The shock oil is marked 500 with no unit, so it is left blank.
- Hobao's dimension drawing gives 6400g, not saying whether a battery is included.
- The ARR version (HB-MTXE) is the same truck without electronics.
Documents
- ManualHyper MTX instruction manual (Hobao USA PDF) (opens in a new tab)Center gearbox and motor steps 39-44, pp. 15-17
- Exploded viewHyper MTX exploded view (Hobao USA PDF) (opens in a new tab)
- Parts listParts list, in the Hyper MTX manual (Hobao USA PDF) (opens in a new tab)pp. 23-26
Sources
- hb-mtxe-c150bu-hyper-mtx-mo…hobao-usa.com (opens in a new tab)
- Manual (PDF)hobao-usa.com (opens in a new tab)
- Manual (PDF)hobao-usa.com (opens in a new tab)
- 005-1.pnghobao-usa.com (opens in a new tab)
- size.pnghobao-usa.com (opens in a new tab)
- 94089-mt-plus-ii-spur-gear-…hobao-usa.com (opens in a new tab)
- 89325hobao-usa.com (opens in a new tab)
- 94088-steel-gear-16t-2pcshobao-usa.com (opens in a new tab)
- 94091n-steel-spur-gear-36t-…hobao-usa.com (opens in a new tab)
- 94002nhobao-usa.com (opens in a new tab)
- 89322hobao-usa.com (opens in a new tab)
- 89421wp-1-waterproof-esc-15…hobao-usa.com (opens in a new tab)
- monster-truck-hyper-mtx-ele…hobao-usa.com (opens in a new tab)
- hobao-hyper-mtxe-monster-tr…shop.robitronic.com (opens in a new tab)
- hb-mtxe-hyper-mtx-monster-t…hobao-usa.com (opens in a new tab)
Every figure on this page traces to one of these. Where they disagreed, the note above says which was used and why.