Name: Free Shipping! X-PRO Thunder 40cc ATV with Chain Transmission, Pull start! Disc Brake! 6in Tires!
Brand: XPro
SKU: free-shipping-x-pro-thunder-40cc-atv-with-chain-transmission-pull-start-disc-brake-6-tires
Availability: InStock

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Free Shipping! X-PRO Thunder 40cc ATV with Chain Transmission, Pull start! Disc Brake! 6in Tires!

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Free Shipping! X-PRO Thunder 40cc ATV with Chain Transmission, Pull start! Disc Brake! 6in Tires!—

$569.95

$199.48

Select Color

Select Assembly Service

From $199.48

Original: $569.95

-65%

Free Shipping! X-PRO Thunder 40cc ATV with Chain Transmission, Pull start! Disc Brake! 6in Tires!—

$569.95

$199.48

The Story

⚙️

Engine

40cc Gas

🔄

Transmission

Auto Pull Start

🏁

Top Speed

10–15 mph

⚖️

Max Load

70 lbs

🪑

Seat Height

22.46"

✅

Certified

EPA Approved

Xingyue 4-Stroke Engine No Oil Mix — X-PRO Thunder 40 40cc Kids ATV

A 4-Stroke Engine in a 40cc Kids ATV — Because Fueling Shouldn't Be Complicated

We equipped the Thunder 40 with a Xingyue 4-stroke air-cooled engine that runs on straight 87 Octane gas — no oil-to-fuel mixing ratios, no 2-stroke oil to keep stocked, no risk of engine damage from a miscalculated mix. Fully automatic chain drive. Pull start. 0.9kW / 6,500 RPM. Top speed 10–15 mph. One fuel type, one step to fill.

⚠ Critical before first start: We ship the Thunder 40 without engine oil in the crankcase — this is standard for new powersports equipment. Add 10W-40 4-stroke motor oil and check the dipstick before the very first start. Running without oil causes permanent damage.

4-stroke means no measuring. Fill with 87 Octane, pull the cord, ride. That's the right fueling experience for a 3-year-old's ATV — and their parent's peace of mind.

Hydraulic Disc Brakes Front Rear — X-PRO Thunder 40 40cc Kids ATV

Hydraulic Disc Brakes Front & Rear — A Safety Specification Most 40cc ATVs Skip

We spec'd the Thunder 40 with hydraulic disc brakes on both the front and rear wheels. Most 40cc ATVs at this price point use drum brakes on one or both wheels — shorter stopping distances and more consistent brake feel at every speed. For a 4-year-old who is still developing reaction time and spatial awareness, we believe the brake specification matters.

We also include an adjustable speed governor so you can set an appropriate maximum speed for your child's current skill level, and a handlebar-mounted engine kill switch for immediate shutoff.

We chose disc brakes on both wheels because when a young rider squeezes the brakes, the gap between "squeeze" and "stopped" should be as short as it can be.

7 Exclusive Hydrographic Designs — X-PRO Thunder 40 40cc Kids ATV

7 Exclusive Hydrographic Designs — Because a First ATV Should Feel Like It Was Chosen

Cartoons, Green Camo, Hip Hop, Hot Rod Flame, Pink Camo, Red Lightning, Starry Camo. We applied each design through hydrographic water-transfer printing — panels submerged through a printed film on water, wrapping the pattern around every curve and contour, then sealed under UV-stable clear coat. Seven exclusive designs that aren't available on any competing 40cc ATV.

We didn't offer seven designs because we had extra inventory to move. We did it because a first ATV should look like the child who rides it chose it — not like the only option available.

X-PRO Licensed U.S. Dealer OEM Parts Support — X-PRO Thunder 40 40cc Kids ATV

X-Pro Dealer Backing — OEM Parts Ready Before the Vehicle Ships

X-Pro has operated as a licensed U.S. powersports dealer for 20+ years. We maintain two company-owned warehouses in California and Texas — not a third-party logistics center, our own facilities, our own staff. OEM replacement parts for the Thunder 40 (ATV-Z06 / LY-ATV-40C) are in those warehouses and ready to ship before the vehicle goes on sale. Frame warranty: 1 year against structural defects. Parts warranty: 90 days against manufacturing defects. Support is handled in-house by our U.S.-based team.

We stocked the parts before we listed the vehicle. Not because we expect problems — because if one comes up, a 3-year-old's riding season shouldn't have to wait for a part to ship from overseas.

Rider Fit Guide

Recommended Age	3–6 years old — direct adult supervision required at all times
Recommended Height	Estimated 3'0" to 4'0" (91–122 cm)
Maximum Weight Capacity	70 lbs (32 kg) — verify rider weight before purchase; do not exceed
Suitable Riding Environments	Flat backyard grass or packed dirt — outdoor daytime use with direct adult supervision

We designed the Thunder 40 for young riders ages 3–6, up to 70 lbs, with a flat outdoor riding area and a parent or guardian who can provide direct supervision at all times. Best fit: height approximately 3'0" to 4'0", in families with backyard grass or packed dirt — and a parent willing to be present for every ride. If your child is at or near 70 lbs, the step-up to our Eagle 110cc ATV (143 lb capacity) is the right choice to avoid outgrowing the Thunder 40 quickly.

Always ensure the vehicle's engine size, speed rating, and weight capacity are appropriate for the rider's age, size, and experience level.

Fit guide is for reference only. Actual fit may vary based on inseam, footwear, and riding posture.

Licensed U.S. Dealer

20+ Years in Business

U.S. Support

Phone & Email, Real People

OEM Parts in Stock

CA & TX Warehouses

Manufacturer Warranty

Frame 1 Year · Parts 90 Days

Key Features

Xingyue 4-Stroke Engine — No Oil Mixing: We equipped the Thunder 40 with a Xingyue 40cc 4-stroke engine that runs on 87 Octane gas only — no oil mixing, no 2-stroke complications. Fully automatic chain drive, pull start. 0.9kW / 6,500 RPM, 10–15 mph. ⚠ Engine NOT pre-filled with oil — add 10W-40 4-stroke motor oil before first start.

Hydraulic Disc Brakes Front & Rear: We spec'd disc brakes on both wheels — shorter stopping distances than drum-brake competitors. Parent-adjustable speed governor. Handlebar kill switch. The brake specification we believe young riders deserve.

7 Exclusive Hydrographic Designs: Cartoons, Green Camo, Hip Hop, Hot Rod Flame, Pink Camo, Red Lightning, Starry Camo. Water-transfer printing sealed under UV-stable clear coat. Seven designs unavailable on competing 40cc ATVs.

Fits Ages 3–6, Max 70 lbs: 22.46" seat height. 4.10-6 tubeless tires. EPA certified gas ATV — NOT for California. Headlight decorative only. Ships UPS/FedEx Ground parcel — no freight appointment.

Reliable U.S. Support, Ready Parts: As a licensed U.S. powersports dealer with 20+ years in business, two company-owned warehouses in California and Texas, and a dedicated in-house team, we keep OEM replacement parts for the Thunder 40 stocked and ready to ship.

Description

We built the Thunder 40 for riders ages 3–6 who are ready for their first gas-powered ATV — and for the parents who need that machine to be straightforward to fuel, capable enough to be safe, and distinctive enough that a child actually wants to ride it. The Xingyue 4-stroke engine uses 87 Octane gas only. No oil mixing. Hydraulic disc brakes on both wheels. Seven hydrographic designs, not available on any competing 40cc ATV.

⚠ Before first start: We ship the Thunder 40 without oil in the engine crankcase — standard for new powersports equipment. Add 10W-40 4-stroke motor oil and check the dipstick before the first start. Running without oil causes permanent engine damage and voids the warranty. The front LED headlight is decorative and does not illuminate — the Thunder 40 is designed for outdoor daytime use under direct adult supervision.

The fully automatic centrifugal chain drive transmission — no clutch, no gear shifting — means a young rider can focus on steering and speed, not mechanical skill. The adjustable speed governor lets parents set an appropriate maximum speed for the child's current development level. The handlebar kill switch provides immediate shutoff from the rider's hands.

Ships UPS Ground or FedEx Ground in a compact box (38"×22"×20", ~95 lbs). No freight scheduling required. Arrives 85% pre-assembled — install 4 wheels, handlebar clamp, front bumper guard, and rear cargo rack (approximately 45–60 min). EPA certified. Not for California. Off-road use only. Maximum load: 70 lbs.

X-Pro has operated as a licensed U.S. powersports dealer for over 20 years. When you buy the Thunder 40 from our store, you are buying from a dealer with two company-owned warehouses in California and Texas, an in-house U.S.-based support team, and OEM replacement parts for the ATV-Z06 stocked before the vehicle went on sale. Frame warranty: 1 year against structural defects. Parts warranty: 90 days against manufacturing defects.

Technical Specifications

Engine & Transmission

Engine Brand	Xingyue
Engine Displacement	40cc
Cylinders	Single Cylinder
Cooling System	Air Cooled
Max Power	0.9 kW / 6,500 RPM
Max Torque	1.6 N·m / 5,000 RPM
Ignition Type	CDI
Transmission	Fully Automatic (Chain Drive)
Start System	Pull Start (Recoil)
Fuel Type	Gasoline (87 Octane Minimum) — No oil mixing
Fuel Tank Capacity	1L
Top Speed	10–15 mph

Brakes & Suspension

Front Brake	Hydraulic Disc Brake
Rear Brake	Hydraulic Disc Brake
Front Suspension	Dual Front Shocks
Rear Suspension	Single Rear Shock
Front Tire	4.10-6 Tubeless
Rear Tire	4.10-6 Tubeless
Wheel Material	Steel Rims

Size & Fit

Overall Length	42"
Overall Width	26.8"
Overall Height	28.7"
Seat Height	22.46"
Ground Clearance	4"
Wheelbase	27.5"
Net Weight	76 lbs
Gross Weight (incl. pkg)	95 lbs
Max Load Capacity	70 lbs
Package Dimensions	38" × 22" × 20"

Safety, Controls & Certification

Engine Kill Switch	Yes — Handlebar Mounted
Speed Governor	Yes — Adjustable
Headlight	Yes — Decorative (Non-functional)
Frame Material	Steel
EPA Certified	Yes
CARB Certified	No — Not for sale in California
Front Bumper Guard	Included
Rear Cargo Rack	Included
Tool Kit	Included
Owner's Manual	Included

Comparison

	X-PRO Thunder 40	Competitor A	Competitor B	Competitor C	Competitor D
Max Load Capacity	70 lbs	70 lbs	70 lbs	66 lbs	70 lbs
Seat Height	22.46"	~22"	~21"	~20"	~22"
Engine Type	4-Stroke (No Mix)	4-Stroke	2-Stroke	4-Stroke	2-Stroke
Front Brake	Hydraulic Disc	Drum	Drum	Drum	Drum
Rear Brake	Hydraulic Disc	Drum	Drum	Drum	Drum
Graphic Designs	7 Hydrographic	Standard Colors	Standard Colors	Standard Colors	Standard Colors
Speed Governor	Yes — Adjustable	Yes	Yes	Not confirmed	Yes
Delivery Method	UPS/FedEx Parcel	Varies	Varies	Varies	Freight
Seller Type	Licensed U.S. Dealer (20+ yr)	3rd-party seller	3rd-party seller	3rd-party seller	3rd-party seller
OEM Parts Availability	In U.S. (CA & TX)	Limited U.S.	Limited U.S.	Limited U.S.	Via importer

Data sourced from publicly available manufacturer/seller listings, July 2026. Competitor names not disclosed. Specifications may vary by model year. Provided for comparative reference only.

Why Buy From Us

Company History

The company behind X-Pro has operated in the U.S. motorcycle and powersports market for over 20 years as a licensed U.S. motorcycle dealer. Not a dropshipper. Not a temporary marketplace seller. Two company-owned warehouses in California and Texas. Every product we sell is backed by a support team, parts inventory, and warranty handling that we manage in-house.

The X-Pro Brand

X-Pro was established in 2018 as a dedicated powersports brand built on over two decades of hands-on U.S. market experience. The product line covers mopeds, scooters, dirt bikes, motorcycles, ATVs, go-karts, and electric powersports — all sold with full dealer backing. When X-Pro entered the market, the affordable powersports space was largely defined by short-term sellers with no replacement parts and no after-sales support. X-Pro was built to operate differently.

Why Families Choose X-Pro for a First Kids' ATV

Buying a first gas-powered ATV for a 3–6 year old comes down to a practical question: does the machine have the right specifications for the age group — and is the seller still going to be there when something needs attention after the sale? We answer that question with measurable specifications: disc brakes on both wheels, 4-stroke engine with no oil mixing, seven design options. And we answer the post-sale question the same way we always have: with OEM parts already stocked in the U.S. and a support team that handles warranty claims in-house.

Warehouses & Fulfillment

We operate two company-owned warehouses — California and Texas. Staffed by our own team. No third-party logistics routing. Inventory is stored, inspected, and shipped from these facilities directly.

After-Sales & Warranty

Every Thunder 40 is covered by our manufacturer Limited Warranty: 1-year frame, 90-day parts. Warranty claims go directly to our U.S.-based support team — not a manufacturer hotline, not an offshore contact form. Our team has access to warehouse inventory and order records to resolve issues efficiently.

Parts Availability

We maintain OEM replacement parts for the Thunder 40 (ATV-Z06 / LY-ATV-40C) in our U.S. warehouses. Parts are stocked before the vehicle goes on sale. Parts orders ship from the same facilities on the same timelines as complete units.

Warranty

Every X-Pro Thunder 40 is covered by our Limited Warranty: • Frame: 1-year warranty against structural defects • Parts: 90-day warranty against manufacturing defects (excludes normal wear items such as tires, brake pads, drive chain, and spark plugs) Warranty claims are handled directly by our U.S.-based support team.

View full warranty policy

Limited Warranty covers manufacturing defects only. Normal wear and tear, damage from accidents, misuse, or unauthorized modifications are not covered.

Assembly & Setup

What's in the Box

Vehicle body (85% pre-assembled), 4 wheels, handlebar assembly, front bumper guard, rear cargo rack, tool kit, owner's manual, and hardware. Helmet is NOT included — required for safe riding, sold separately.

What Needs Assembly

Install 4 wheels, mount handlebar clamp, attach front bumper guard, and secure rear cargo rack. Two-person assembly recommended for wheel mounting. Add 10W-40 4-stroke motor oil before first start — engine does NOT ship pre-filled with oil. Apply thread-locker (Loctite) to all bolts before the first ride.

Assembly Time

Approximately 45–60 minutes with basic hand tools. Refer to the included owner's manual for step-by-step instructions. Professional mechanic assembly is highly recommended — improper assembly voids safety guarantees and is a leading cause of early mechanical issues.

Before You Buy

1 · Add Engine Oil Before First Start (Critical)

We ship the Thunder 40 without engine oil in the crankcase — this is standard for new powersports equipment, not an error. Before the very first start, add 10W-40 4-stroke motor oil and verify the dipstick is at the correct level. Running the engine without oil — even for a brief moment — causes permanent engine damage and voids the warranty. This is the single most important step before first use.

2 · Not for California

The Thunder 40 is EPA certified but does not meet California Air Resources Board (CARB) emission standards. We cannot sell or ship this vehicle to California addresses. Off-road use only in all other U.S. states — not street legal anywhere.

3 · Shipping — UPS/FedEx Ground Parcel

Your Thunder 40 ships UPS Ground or FedEx Ground in a compact box (38"×22"×20", ~95 lbs). Standard parcel delivery — no freight scheduling, no delivery appointment, no carrier coordination required. Typically 3–7 business days from our California or Texas warehouse.

4 · Assembly — 45–60 Minutes

The Thunder 40 arrives 85% pre-assembled. Install 4 wheels, handlebar clamp, front bumper guard, and rear cargo rack. Two adults recommended. Apply thread-locker (Loctite) to all bolts before the first ride — vibration during riding will loosen factory-set hardware, and this is a required pre-ride step. Professional mechanic assembly is highly recommended.

5 · Weight Limit — 70 lbs Maximum

Maximum load is 70 lbs (32 kg). Verify your child's current weight before purchasing. If they are at or near 70 lbs, we recommend the X-PRO Eagle 110cc ATV (143 lb capacity) to avoid outgrowing this machine quickly. Do not exceed the weight limit under any circumstances.

6 · Headlight — Decorative Only

The front LED headlight is decorative and does not provide functional illumination. The Thunder 40 is designed for outdoor daytime riding under direct adult supervision. Do not ride at dusk, after dark, or in low-visibility conditions.

7 · Pull Start & Speed Governor

To start: set throttle to idle and pull the T-handle firmly and steadily. For riders ages 3–5, we recommend that a parent starts the engine. The adjustable speed governor should be set to its minimum position before the first ride — increase the setting gradually as the child's skill and confidence develop. Maximum speed: 10–15 mph at full throttle.

8 · Safety & Supervision Requirements

The Thunder 40 is designed for riders ages 3–6, up to 70 lbs, under direct adult supervision at all times. Always wear a properly fitted, approved helmet and full protective gear — helmet is not included with the vehicle. Off-road use only — outdoor, flat surface, daytime, with an adult present for every ride.

Support Center & Resources

Contact Us — Phone, Email & Video Call
Order Parts for Thunder 40 (ATV-Z06)
Warranty Policy

FAQ

Does this ATV come with engine oil?

No — we ship the Thunder 40 without oil in the engine crankcase, which is standard for new powersports equipment. You must add 10W-40 4-stroke motor oil before the first start. Running the engine without oil — even briefly — causes permanent damage and voids the warranty.

What age and weight is the Thunder 40 designed for?

We designed the Thunder 40 for riders ages 3–6, up to 70 lbs. Seat height is 22.46 inches. Direct adult supervision is required at all times. If your child is at or near 70 lbs, we recommend stepping up to the Eagle 110cc ATV (143 lb capacity) to avoid outgrowing this machine quickly.

Does it require oil mixing in the fuel?

No — the Xingyue 4-stroke engine runs on 87 Octane unleaded gas only. No oil mixing required. Fuel tank capacity: 1L. Use fresh, unblended 87 Octane gas.

What is the top speed, and can it be limited?

Top speed is 10–15 mph at full throttle. We include an adjustable speed governor that should be set to its minimum position before the first ride. Increase the setting gradually as the child's skills and confidence develop. Contact our support team if you need help adjusting the governor.

Is the Thunder 40 available in California?

No. The Thunder 40 is EPA certified but does not meet California Air Resources Board (CARB) emission standards. We cannot sell or ship this vehicle to California addresses. If you're in California and looking for an ATV, contact our team to discuss what CARB-compliant options we may have.

Does the headlight work?

The front LED headlight is decorative and does not provide functional illumination. We designed the Thunder 40 for outdoor daytime riding under direct adult supervision only — not for dusk or nighttime use.

Does it require freight delivery?

No — the Thunder 40 ships UPS Ground or FedEx Ground in a compact box (38"×22"×20", ~95 lbs). Standard parcel delivery with no freight appointment required. Typically 3–7 business days from our California or Texas warehouse.

How much assembly is required, and how long does it take?

The Thunder 40 arrives 85% pre-assembled. You'll install 4 wheels, the handlebar clamp, front bumper guard, and rear cargo rack — approximately 45–60 minutes with basic hand tools. Professional mechanic assembly is highly recommended. Add 10W-40 engine oil and apply thread-locker to all bolts before the first ride.

Who is the Thunder 40 for?

We designed the Thunder 40 for young riders ages 3–6, up to 70 lbs, in families with a flat outdoor riding area and the ability to provide direct adult supervision on every ride. A parent should start the engine for riders ages 3–5. It's the right machine for a child's first gas-powered ATV experience — with disc brakes on both wheels, a 4-stroke engine, and seven design options.

How does the Thunder 40 compare to the Scout 40?

Both the Thunder 40 (ATV-Z06) and Scout 40 (ATV-Z04) are X-Pro 40cc kids ATVs with the same Xingyue 4-stroke engine, same age/weight range (3–6, 70 lbs), and similar specifications. The primary difference is body style and graphic design options. Compare our product listings or contact our team to decide which fits your child's preference.

What does the warranty cover?

Every Thunder 40 is covered by our X-Pro Limited Warranty: 1-year frame warranty against structural defects, 90-day parts warranty against manufacturing defects. Normal wear items (tires, brake pads, chain, spark plugs) and damage from misuse, accidents, or modifications are excluded. View the full policy at xprousa.com/pages/warranty-policy.

Is the Thunder 40 suitable for first-time riders?

Yes — the fully automatic transmission (no clutch, no shifting) means first-time riders can focus on steering and speed control rather than mechanical skill. Set the speed governor to minimum for the first several sessions and supervise directly at all times. We recommend that a parent start the engine for riders ages 3–5.

What type of brakes does the Thunder 40 have?

Hydraulic disc brakes on both front and rear wheels. We specified disc brakes on both wheels rather than the drum brakes found on competing 40cc ATVs — for shorter stopping distances and more consistent brake feel for young riders with developing reaction times.

How does the pull start work?

Set the throttle to idle position and pull the T-handle firmly and steadily. Cold starts typically require 2–4 pulls; warm restarts are usually immediate. For riders ages 3–5, we recommend that a parent starts the engine each session. There is no battery, no electric start — this is a recoil pull start only.

What type of fuel does the Thunder 40 use?

87 Octane or higher unleaded gasoline only. No oil mixing. Fuel tank capacity: 1L. Use fresh fuel — treat or drain for storage over 30 days to prevent carburetor clogging.

Other X-Pro Models

Model	Best For	Key Difference
X-PRO Scout 40 (ATV-Z04)	Riders who want the same 40cc age group in a different body style	Same Xingyue 4-stroke engine, same age/weight range — different body design; compare design options to decide between models
X-PRO Eagle 110cc (ATV-P001)	Riders ages 8+, or children at or near the 70 lb weight limit of the Thunder 40	110cc, 143 lb capacity, 21.26" seat height, electric start — step-up when child outgrows the Thunder 40
X-PRO Hawk 125 (ATV-P003)	Teen riders ages 12+ up to 198 lbs ready for a full-capability 125cc ATV	125cc automatic with reverse, remote kill switch, 19"/18" tires, 198 lb capacity — the full step-up from youth ATVs