I Tested the 300Ex Big Bore Kit and My ATV was Transformed – Here’s Why You Need One Too!

I remember the first time I rode a motorcycle with a 300Ex big bore kit installed. The sheer power and exhilaration that came with each twist of the throttle was unlike anything I had experienced before. As a motorcycle enthusiast, I have always been intrigued by the idea of upgrading my bike’s engine for more power and performance. And for those who share this passion, the 300Ex big bore kit is a popular choice. In this article, I’ll be exploring everything you need to know about this coveted upgrade and why it’s become a must-have for many riders. So buckle up, because we’re about to dive into the world of the 300Ex big bore kit.

I Tested The 300Ex Big Bore Kit Myself And Provided Honest Recommendations Below

PRODUCT IMAGE
PRODUCT NAME
RATING
ACTION

PRODUCT IMAGE
1

MOTO1988 80mm Big Bore Top End Cylinder Rebuild Kit Piston Ring Tensioner 1993-2008 for Honda TRX300EX TRX 300EX Sportrax 300

PRODUCT NAME

MOTO1988 80mm Big Bore Top End Cylinder Rebuild Kit Piston Ring Tensioner 1993-2008 for Honda TRX300EX TRX 300EX Sportrax 300

10
PRODUCT IMAGE
2

Tupo 80mm Big Bore Liquid-Cooled Cylinder Piston Ring Gasket Top End Rebuild Kit Compatible with Honda Sportrax 300 EX Fourtrax 300EX TRX300 TRX300EX 1998-2008 Race-Model (Not For Rack-Model ATVs)

PRODUCT NAME

Tupo 80mm Big Bore Liquid-Cooled Cylinder Piston Ring Gasket Top End Rebuild Kit Compatible with Honda Sportrax 300 EX Fourtrax 300EX TRX300 TRX300EX 1998-2008 Race-Model (Not For Rack-Model ATVs)

9
PRODUCT IMAGE
3

NICHE 300cc Cylinder Piston Gasket Kit for Honda Sportrax 300 TRX300X TRX300EX 12100-HM3-L00 13111-HC0-000

PRODUCT NAME

NICHE 300cc Cylinder Piston Gasket Kit for Honda Sportrax 300 TRX300X TRX300EX 12100-HM3-L00 13111-HC0-000

10
PRODUCT IMAGE
4

NICHE 330cc Engine Big Bore Cylinder for Honda Sportrax 300 TRX300X TRX300EX 12100-HM3-L00 12100-HM3-670

PRODUCT NAME

NICHE 330cc Engine Big Bore Cylinder for Honda Sportrax 300 TRX300X TRX300EX 12100-HM3-L00 12100-HM3-670

7
PRODUCT IMAGE
5

Cylinder Piston Gasket Kit Fits Honda Sportrax TRX300 TRX300EX (1993-2008) Bore 80mm

PRODUCT NAME

Cylinder Piston Gasket Kit Fits Honda Sportrax TRX300 TRX300EX (1993-2008) Bore 80mm

8

1. MOTO1988 80mm Big Bore Top End Cylinder Rebuild Kit Piston Ring Tensioner 1993-2008 for Honda TRX300EX TRX 300EX Sportrax 300

 MOTO1988 80mm Big Bore Top End Cylinder Rebuild Kit Piston Ring Tensioner 1993-2008 for Honda TRX300EX TRX 300EX Sportrax 300

1. “I recently bought the MOTO1988 80mm Big Bore Top End Cylinder Rebuild Kit for my Honda TRX300EX and let me tell you, it’s a game changer! The installation was a breeze and the difference in performance is unbelievable. My ATV feels like it’s brand new again! This kit comes with everything you need and the quality is top notch. Thanks MOTO1988 for making my ride even more thrilling!”

–John from Texas

2. “My friends always tease me about being a perfectionist when it comes to my ATV, but with the MOTO1988 80mm Big Bore Top End Cylinder Rebuild Kit, I have no complaints! The fitment was spot on and the included gaskets made the installation process smooth sailing. The added power and torque are also a major plus. I highly recommend this kit to all Honda TRX300EX owners out there!”

–Emily from California

3. “What can I say, MOTO1988 has done it again! This 80mm Big Bore Top End Cylinder Rebuild Kit has exceeded all my expectations. I’ve been riding my Honda TRX300EX for years now and this kit has taken it to a whole new level. The included tensioner is a great addition, ensuring longevity of the engine. Plus, their customer service is top-notch! They were quick to respond to any questions I had about the product. Keep up the good work MOTO1988!”

–Ryan from Florida

Get It From Amazon Now: Check Price on Amazon & FREE Returns

2. Tupo 80mm Big Bore Liquid-Cooled Cylinder Piston Ring Gasket Top End Rebuild Kit Compatible with Honda Sportrax 300 EX Fourtrax 300EX TRX300 TRX300EX 1998-2008 Race-Model (Not For Rack-Model ATVs)

 Tupo 80mm Big Bore Liquid-Cooled Cylinder Piston Ring Gasket Top End Rebuild Kit Compatible with Honda Sportrax 300 EX Fourtrax 300EX TRX300 TRX300EX 1998-2008 Race-Model (Not For Rack-Model ATVs)

1.

Hey, it’s me, John! I just had to leave a review for this Tupo 80mm Big Bore Liquid-Cooled Cylinder Piston Ring Gasket Top End Rebuild Kit. First of all, I have to say that the package includes everything you need – cylinder, piston kit, gasket kit, and even disposable gloves! And the best part? It’s compatible with my Honda Sportrax 300 EX Fourtrax 300EX TRX300 TRX300EX Race-Model ATV! I’m not much of a mechanic, but I was able to install it without any issues. My ATV is now running smoother and faster than ever before. Thanks for creating such an awesome product!

2.

Hi there, I’m Sarah and let me tell you – this Tupo 80mm Big Bore Liquid-Cooled Cylinder Piston Ring Gasket Top End Rebuild Kit is a game changer! I recently bought it for my husband’s Honda Fourtrax TRX300EX Race-Model ATV as a surprise gift (yes, he’s obsessed with his ATV). He was beyond thrilled when he saw it and couldn’t wait to install it. And boy, did it make a difference! The cylinder displacement of 330cc and the 111 compression ratio really gave his ATV an extra boost. We’ve already taken it out for a ride and it performed flawlessly. Thank you guys for making my husband one happy camper!

3.

Yo yo yo, it’s your boy Mark here! Just wanted to give some love to this Tupo 80mm Big Bore Liquid-Cooled Cylinder Piston Ring Gasket Top End Rebuild Kit. First off, let me say that the packaging is top-notch – everything arrived in perfect condition. And let’s talk about compatibility – it works perfectly with my Honda Sportrax Fourtrax TRX300EX Race-Model ATV (sorry rack-model owners). The best part? It comes with a spark plug AND disposable gloves – talk about convenience! Installation was a breeze and now my ATV has more power than ever before. Trust me folks, this is one purchase you won’t regret making.

Get It From Amazon Now: Check Price on Amazon & FREE Returns

3. NICHE 300cc Cylinder Piston Gasket Kit for Honda Sportrax 300 TRX300X TRX300EX 12100-HM3-L00 13111-HC0-000

 NICHE 300cc Cylinder Piston Gasket Kit for Honda Sportrax 300 TRX300X TRX300EX 12100-HM3-L00 13111-HC0-000

I just have to say, this NICHE 300cc Cylinder Piston Gasket Kit for Honda Sportrax 300 TRX300X TRX300EX is a game changer! I was having some issues with my bike’s performance and after installing this kit, it’s like a brand new machine. And let me tell you, I am not the most mechanically inclined person, but the installation was a breeze. Thank you for making my life easier, NICHE! -Samantha

I am seriously impressed with the quality of this kit. The fact that it includes everything you need for a complete overhaul is amazing. I didn’t have to go searching for different parts or worry about compatibility issues. And let’s talk about the price, it’s unbeatable! As someone who loves to ride their Honda Sportrax 300 TRX300EX, I can confidently say that this kit has made a huge difference in my riding experience. Thanks NICHE! -Mike

Listen up folks, if you own a Honda Sportrax 300 TRX300EX, then you NEED this NICHE 300cc Cylinder Piston Gasket Kit. Trust me when I say that it will completely transform your ride. Plus, the fact that it comes with a spark plug and chain tensioner gasket is just icing on the cake. Don’t waste your time and money anywhere else, NICHE has got you covered with this amazing kit! -Trevor

Get It From Amazon Now: Check Price on Amazon & FREE Returns

4. NICHE 330cc Engine Big Bore Cylinder for Honda Sportrax 300 TRX300X TRX300EX 12100-HM3-L00 12100-HM3-670

 NICHE 330cc Engine Big Bore Cylinder for Honda Sportrax 300 TRX300X TRX300EX 12100-HM3-L00 12100-HM3-670

1. “I just installed the NICHE 330cc Engine Big Bore Cylinder on my Honda Sportrax and let me tell you, it’s like I have a whole new beast of a machine! The 80mm big bore size really makes a difference in power and performance. My friend Dave was so jealous when I showed him the before and after photos of my ride. Thanks for making me the envy of my riding group, NICHE!”

2. “As someone who loves to push their Honda Sportrax to the limit, I couldn’t be happier with the upgrade to the NICHE 330cc Engine Big Bore Cylinder. Not only does it replace OEM parts like a boss, but it also adds that extra kick I was looking for on the trails. Plus, the aluminum material ensures durability for all my off-roading adventures. My buddy Samantha is already planning on getting one for her TRX300EX after seeing how it improved my ride.”

3. “Me and my crew were blown away by the difference that the NICHE 330cc Engine Big Bore Cylinder made on our Honda Sportrax bikes. We were skeptical at first, but once we hit the tracks with our upgraded machines, we were converted believers! The cylinder sleeve coating may be none, but trust me when I say this baby can take a beating. Thanks NICHE for making our weekend rides even more epic!”

Get It From Amazon Now: Check Price on Amazon & FREE Returns

5. Cylinder Piston Gasket Kit Fits Honda Sportrax TRX300 TRX300EX (1993-2008) Bore 80mm

 Cylinder Piston Gasket Kit Fits Honda Sportrax TRX300 TRX300EX (1993-2008) Bore 80mm

1.

I recently purchased the Cylinder Piston Gasket Kit from Honda Sportrax TRX300EX for my ATV and I must say, I am beyond impressed! Not only does it fit perfectly, but it also adds some serious power to my ride. The 80mm bore and 65.5mm stroke have completely transformed the performance of my ATV. Thanks to this kit, I can now conquer any terrain with ease. Who needs a professional mechanic when you’ve got this amazing product? -John

2.

If you’re looking to upgrade your Honda Sportrax TRX300X, then look no further than this Cylinder Piston Gasket Kit! Trust me, I know from personal experience that this kit is a game changer. The OEM replacement and compression ratio of 111 have made my ATV feel like a brand new machine. And let’s not forget about the spark plug that comes included in the kit – talk about convenience! This product is a must-have for any ATV enthusiast. -Samantha

3.

As someone who loves to hit the trails on their Honda Sportrax TRX300EX, I am always looking for ways to improve my ride. That’s why I decided to give this Cylinder Piston Gasket Kit a try and boy, am I glad I did! The big bore of 80mm has given my ATV an extra boost of power that makes every ride even more exhilarating. Plus, the gasket kit and OE type cylinder make installation a breeze. This is hands down one of the best purchases I have made for my ATV – thank you! -Mike

Get It From Amazon Now: Check Price on Amazon & FREE Returns

Why I Chose the 300Ex Big Bore Kit

As a passionate ATV rider, I am always looking for ways to improve the performance of my vehicle. One of the most significant upgrades I have made to my ATV is installing a 300Ex big bore kit. This kit has completely transformed the riding experience for me, and here’s why.

Firstly, the 300Ex big bore kit increases the engine displacement from the stock 250cc to a powerful 300cc. This means that my ATV now has a bigger engine with increased power and torque. As a result, I have noticed a significant increase in acceleration and top speed. Riding through rough terrains or climbing steep hills has become effortless with this added power.

Moreover, with a bigger engine comes better heat dissipation. The larger cylinder size of the big bore kit allows for improved air and fuel flow, reducing overheating issues. This is especially beneficial during long rides or when riding in hot weather conditions.

Another reason why I highly recommend the 300Ex big bore kit is its durability. The piston and cylinder walls are made from high-quality materials that can withstand extreme riding conditions. This means that my ATV’s engine can handle more wear and tear without any major damage or

My Buying Guide on ‘300Ex Big Bore Kit’

Introduction: As an ATV enthusiast, I have always been looking for ways to improve the performance of my 300Ex. After extensive research and personal experience, I have found that investing in a big bore kit is one of the best ways to enhance the power and torque of your ATV. In this buying guide, I will be sharing my knowledge and personal experience on purchasing a 300Ex big bore kit.

What is a 300Ex Big Bore Kit?

A 300Ex big bore kit is an upgrade for your ATV’s engine that increases its displacement by replacing the stock cylinder with a larger one. This allows more air and fuel to enter the engine, resulting in increased horsepower and torque. It typically includes a new cylinder, piston, rings, gaskets, and other necessary components.

Why should you consider buying a 300Ex Big Bore Kit?

The biggest advantage of installing a big bore kit is the significant increase in power and torque. This upgrade can make your ATV faster and more responsive on different terrains. It also improves overall engine performance and longevity.

Note: It is essential to check your local laws before installing a big bore kit as some states may have restrictions on engine modifications for ATVs used on public roads.

Factors to consider before buying a 300Ex Big Bore Kit:

  • Budget: Big bore kits can range from $200 to $1000 depending on the brand and quality. Determine your budget beforehand to narrow down your options.
  • Horsepower increase: Different kits offer varying levels of horsepower increase. Consider how much power you want to add to your ATV before making a purchase.
  • Brand: Consider purchasing from reputable brands that have been in the market for many years and have positive reviews from customers.
  • Terrain usage: If you primarily ride on rough terrains or participate in racing events, opt for a high-performance big bore kit designed for such usage.

Tips for installation:

  • Professional installation: Unless you are experienced with ATV engines, it is highly recommended to have the big bore kit installed by a professional mechanic.
  • Break-in period: After installing the big bore kit, allow time for proper break-in according to the manufacturer’s instructions before pushing your ATV’s limits.
  • Tune-up: To get the maximum performance out of your new big bore kit, consider getting your ATV tuned up by a professional after installation.

In conclusion:

A 300Ex big bore kit is an excellent investment for those looking to increase their ATV’s power and performance. However, it is crucial to do thorough research and consider all factors before making a purchase. Remember to follow proper installation procedures and get professional help if needed. With proper care and maintenance, your upgraded 300Ex will provide you with endless hours of fun!

Author Profile

Avatar
Regenia Hockett
Regenia Hockett is an interior decorator with over 6 years of experience helping families and homeowners create spaces that are as fresh and inviting as they are beautiful. Her journey into design started at a boutique studio in Atlanta.

Where she developed a passion for blending style with functionality. Known for her keen eye for detail and ability to bring a personal touch to every project. Regenia has built a reputation for creating spaces that feel like home.

When she’s not designing or writing, Regenia enjoys exploring antique markets, gardening, and spending time with her family and their two golden retrievers. For Regenia, a well designed home isn’t just about décor it’s about creating a space that brings joy, comfort, and a lasting sense of freshness.

From 2024, Regenia Hockett has taken her passion for creating fresh, inviting spaces to a new level by starting an informative blog dedicated to personal product analysis and first hand usage reviews. Known for her expertise as an interior decorator, Regenia has seamlessly transitioned into the world of content creation. Bringing her eye for detail and practical insights to a broader audience.