Crank it up to WHACK!
Watch the engine fly out!

Build this super-fast LEGO Technic racer, featuring a pull-back motor and engine pop-out action. Combine with BASH! for a crazy combo model.

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🏛 Technic
Set #42072

WHACK!

WHACK.

🏆 Best For: Younger LEGO fans and those new to Technic building ⏱ 1.0 hr build 🧩 135 pcs
★★★☆☆ 3.5

Fans appreciate the set's simple build and fun crash feature, making it a great entry point for Technic beginners. However, some find it lacking in complexity and wish for more advanced functionality.

📝 Our Take

WHACK! is a fun, entry-level Technic set with a cool action feature. The pull-back motor and engine pop-out provide immediate playability and introduce basic Technic concepts.

This set is perfect for younger builders getting into Technic. It's a quick build with a satisfying payoff, and the crash feature adds a lot of excitement.

Skip this if you're looking for a complex or challenging build. Consider larger Technic sets with more intricate gear systems and functions.

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How does the pull-back motor work in this set? Is it possible to combine this set with BASH! without instructions? What are the best ways to display this set? How does this set compare to other small Technic cars?

🧱 Building Experience

🧩
135
Pieces
1.0h
Build Time
📊
Beginner
Difficulty
Build Highlights:
  • Simple and straightforward construction
  • Introduction to pull-back motor mechanisms
  • Satisfying engine pop-out function
  • Durable design for crash testing

📈 Investment Analysis

→ Price stable
C+
Investment Grade
⏳ Active
WHACK! is a small, retired Technic set that may see modest appreciation over time. Its low price point and simple design don't make it a prime investment target, but its play feature and potential for combined builds with BASH! could attract some collectors. The set's value is likely tied to its complete condition and original packaging.

Not Financial Advice: Content is for educational purposes only. Past performance doesn't guarantee future results. Full disclaimer

📖 About This Set

Experience the amazing power and acceleration of this high-speed LEGO® WHACK! model, featuring a lime-green, red and gray color scheme with racing stickers, sturdy front bumper, large rear spoiler and wide black rims with low profile tires. This advanced building set is equipped with a pull-back motor and a new-for-December-2017 engine pop-out function, which is activated on impact. Combine with the 42073 BASH! pull-back model for extended play possibilities or to create the WHACK! ‘N' BASH! combi model.

  • Features a powerful pull-back motor, sturdy front bumper, large rear spoiler, wide black rims with low profile tires and an engine pop-out function, which is activated on impact.
  • Check out the lime-green, red and gray color scheme with cool racing stickers.
  • Bring on the 42073 BASH! and let the race begin!
  • Activate the pull-back motor to launch the high-speed WHACK!
  • New-for-December-2017. See the engine fly out of the vehicle body on impact… WHACK!
  • This LEGO® Technic advanced building set is designed to provide an immersive and rewarding building experience.
  • Combine with the 42073 BASH! to create an awesome WHACK! ‘N’ BASH! combi model with 2 pop-out engines!
  • Suitable for ages 7-14.
  • WHACK! measures over 2” (6cm) high, 6” (17cm) long and 3” (9cm) wide.
  • Combi WHACK! ‘N' BASH! model measures over 3” (9cm) high, 7” (20cm) long and 3” (10cm) wide.

Compare Similar Sets

Compared to larger Technic sets, WHACK! is a much simpler and more affordable option. It's a good starting point for younger builders, but those seeking complexity should consider sets like the Stunt Bike or other mid-range Technic vehicles. The play feature is the main draw, setting it apart from static display models.

📦 Full Parts Inventory - 41 unique parts • 129 total pieces

Technic Pin Connector Hub with 2 Perpendicular Axles Technic Pin Conne...
Part #: 10197 Dark Bluish Gray
Technic Axle Pin 3L with Friction Ridges Lengthwise and 1L Axle Technic Axle Pin ...
Part #: 11214 Dark Bluish Gray
Technic Panel Curved 11 x 3 with 10 Pin Holes through Panel Surface Technic Panel Cur...
Part #: 11954 Black
Pullback Motor 6 x 3 x 5 Pullback Motor 6 ...
Part #: 12799 Dark Bluish Gray
Technic Pin Connector Round 1L [Beam] Technic Pin Conne...
Part #: 18654 Dark Bluish Gray
Tile 1 x 4 with Groove Tile 1 x 4 with G...
Part #: 2431 Lime
Technic Pin with Friction Ridges Lengthwise and Center Slots Technic Pin with ...
Part #: 2780 10× Black
Technic Axle and Pin Connector Angled #1 Technic Axle and ...
Part #: 32013 Black
Technic Axle and Pin Connector Angled #3 - 157.5° Technic Axle and ...
Part #: 32016 Black
Technic Pin Long with Friction Ridges Lengthwise and Stop Bush [3 Lateral Holes, Big Pin Hole] Technic Pin Long ...
Part #: 32054 Red
Technic Axle 2 Notched Technic Axle 2 No...
Part #: 32062 Red
Technic Axle 5 Technic Axle 5
Part #: 32073 Light Bluish Gray
Technic Bush 1/2 Smooth with Axle Hole Semi-Reduced Technic Bush 1/2 ...
Part #: 32123b Yellow
Technic Beam 2 x 4 L-Shape Thick Technic Beam 2 x ...
Part #: 32140 Lime
Technic Beam 2 x 4 L-Shape Thick Technic Beam 2 x ...
Part #: 32140 Black
Technic Beam 3 x 5 L-Shape with Quarter Ellipse Thin Technic Beam 3 x ...
Part #: 32250 Dark Bluish Gray
Technic Beam 1 x 15 Thick Technic Beam 1 x ...
Part #: 32278 Light Bluish Gray
Technic Axle and Pin Connector Perpendicular Double Technic Axle and ...
Part #: 32291 Light Bluish Gray
Technic Beam 1 x 5 Thick Technic Beam 1 x ...
Part #: 32316 Red
Technic Beam 1 x 3 Thick Technic Beam 1 x ...
Part #: 32523 Light Bluish Gray
Technic Beam 3 x 5 L-Shape Thick Technic Beam 3 x ...
Part #: 32526 Dark Bluish Gray
Sticker Sheet for Set 42072-1 Sticker Sheet for...
Part #: 36513 [No Color/Any Color]
Technic Brick 1 x 4 [3 Pin Holes] Technic Brick 1 x...
Part #: 3701 Black
Technic Axle 8 Technic Axle 8
Part #: 3707 Red
Technic Axle 12 Technic Axle 12
Part #: 3708 Black
Plate 1 x 4 Plate 1 x 4
Part #: 3710 Lime
Technic Bush Technic Bush
Part #: 3713 Light Bluish Gray
Technic Axle and Pin Connector Perpendicular Double Split Technic Axle and ...
Part #: 41678 Dark Bluish Gray
Technic Axle and Pin Connector Perpendicular 3L with 2 Pin Holes Technic Axle and ...
Part #: 42003 10× Dark Bluish Gray
Technic Pin 1/2 Technic Pin 1/2
Part #: 4274 Blue
Technic Axle 7 Technic Axle 7
Part #: 44294 Yellow
Tyre 43.2 x 22 ZR Tyre 43.2 x 22 ZR
Part #: 44309 Black
Technic Axle 3 Technic Axle 3
Part #: 4519 Yellow
Wheel 30.4 x 20 without Pinholes, with Reinforced Rim Wheel 30.4 x 20 w...
Part #: 56145 Black
Technic Beam 1 x 2 Thick with Pin Hole and Axle Hole Technic Beam 1 x ...
Part #: 60483 Light Bluish Gray
Technic Beam 3 x 3 T-Shape Thick Technic Beam 3 x ...
Part #: 60484 Light Bluish Gray
Technic Panel Fairing # 4 Small Smooth Long, Side B Technic Panel Fai...
Part #: 64391 Lime
Technic Panel Fairing # 3 Small Smooth Long, Side A Technic Panel Fai...
Part #: 64683 Lime
Technic Pin Long with Friction Ridges Lengthwise, 2 Center Slots Technic Pin Long ...
Part #: 6558 22× Blue
Wave / Flame Rounded Large with Marbled Trans-Yellow Pattern Wave / Flame Roun...
Part #: 85959pat0003 Trans-Red
Technic Axle 4 with Stop Technic Axle 4 wi...
Part #: 87083 Dark Bluish Gray
Plate Special 3 x 4 with 1 x 4 Center Studs [Plain] Plate Special 3 x...
Part #: 88646 Black
This set is a good source of basic Technic pins and connectors, useful for MOC builders needing these common elements. The black tires are also a valuable addition to any Technic parts collection.

💎 Notable Parts

Blue Technic Pin Long with Friction Ridges Lengthwise, 2 Center Slots (22x) $1.10
Black Technic Pin with Friction Ridges Lengthwise and Center Slots (10x) $0.50
Dark Bluish Gray Technic Axle and Pin Connector Perpendicular 3L with 2 Pin Holes (10x) $1.00
Black Tyre 43.2 x 22 ZR (4x) $2.00
Est. BrickLink Part Value
$4.60

💡 MOC Potential

🚗 Small go-kart or buggy variations
🤖 Simple walking or rolling robot
🚗 Alternate car designs with modified crash features

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📖 Building Instructions 4

WHACK! Instructions
42072_X_WHACK N BASH
Download PDF
WHACK! Instructions
42072_X_Measurements
Download PDF
WHACK! Instructions
BI 3004/52, 42072 V29
Download PDF
WHACK! Instructions
BI 3004/52, 42072 V39
Download PDF

Charts Inventory Statistics

41
Unique Parts
129
Total Pieces
0
Minifigures
Inventory Version: 1