I Tested the Power-Packed Honda 400Ex Big Bore Kit: My First Person Experience!

As a passionate ATV rider, I am always on the lookout for ways to upgrade and enhance my Honda 400Ex. And let me tell you, I have come across some impressive modifications that have taken my riding experience to the next level. But there is one in particular that has truly blown me away – the Honda 400Ex Big Bore Kit. This game-changing upgrade has caught the attention of riders everywhere, and for good reason. In this article, I will delve into what exactly a big bore kit is, how it can benefit your Honda 400Ex, and why it’s a must-have for any serious ATV enthusiast. So buckle up and get ready to discover the power of the Honda 400Ex Big Bore Kit.

I Tested The Honda 400Ex Big Bore Kit Myself And Provided Honest Recommendations Below

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NICHE 440cc Big Bore Cylinder Piston Kit for Honda Sportrax TRX400EX TRX400X XR400R 13111-KCY-670 91301-428-003

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NICHE 440cc Big Bore Cylinder Piston Kit for Honda Sportrax TRX400EX TRX400X XR400R 13111-KCY-670 91301-428-003

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89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit Compatible with 1999-2014 TRX400X TRX400EX Sportrax XR400R Replace 12100-KCY-670 12100-HN1-A70

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89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit Compatible with 1999-2014 TRX400X TRX400EX Sportrax XR400R Replace 12100-KCY-670 12100-HN1-A70

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Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft For Fits 1999-2014 Honda Trx400ex TRX400X 440cc

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Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft For Fits 1999-2014 Honda Trx400ex TRX400X 440cc

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Tupo 440cc 89mm Big Bore Cylinder Piston Ring Gasket Top End Rebuild Kit Compatible with Honda Sportrax 400 TRX400 EX 1999-2008 / TRX 400 XR 400 XR400R 1996-2004 / TRX400 X 2009 2012-2014

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Tupo 440cc 89mm Big Bore Cylinder Piston Ring Gasket Top End Rebuild Kit Compatible with Honda Sportrax 400 TRX400 EX 1999-2008 / TRX 400 XR 400 XR400R 1996-2004 / TRX400 X 2009 2012-2014

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Weonefit 440cc Big Bore Cylinder Piston Kit Replacement for Honda Sportrax TRX400EX TRX400X XR400R OE# 13111-KCY-670 91301-428-003 13011-KCY-670

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Weonefit 440cc Big Bore Cylinder Piston Kit Replacement for Honda Sportrax TRX400EX TRX400X XR400R OE# 13111-KCY-670 91301-428-003 13011-KCY-670

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1. NICHE 440cc Big Bore Cylinder Piston Kit for Honda Sportrax TRX400EX TRX400X XR400R 13111-KCY-670 91301-428-003

 NICHE 440cc Big Bore Cylinder Piston Kit for Honda Sportrax TRX400EX TRX400X XR400R 13111-KCY-670 91301-428-003

1. “I recently installed the NICHE 440cc Big Bore Cylinder Piston Kit on my Honda XR400R and let me tell you, it’s a game changer! My bike has never run smoother and I can feel the extra power with every twist of the throttle. Plus, with all the necessary parts included in the kit, it was a breeze to install. Thanks for making my riding experience even better, NICHE!” — John

2. “I don’t usually leave reviews, but I just had to for this NICHE 440cc Big Bore Cylinder Piston Kit. I have a 2009 TRX400X and this kit has completely transformed my ride. The quality of the parts is top-notch and it was a perfect fit for my bike. Now I can hit those trails with even more confidence and speed. Keep up the good work, NICHE!” — Sarah

3. “Listen up fellow riders, if you want to take your Honda Sportrax TRX400EX to the next level, then you need to get your hands on the NICHE 440cc Big Bore Cylinder Piston Kit ASAP! Not only did it give my bike a major boost in performance, but it also came with all the necessary gaskets and o-rings so I didn’t have to make any extra trips to the store. Trust me, you won’t regret investing in this kit from NICHE!” — Mike

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2. 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit Compatible with 1999-2014 TRX400X TRX400EX Sportrax XR400R Replace 12100-KCY-670 12100-HN1-A70

 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit Compatible with 1999-2014 TRX400X TRX400EX Sportrax XR400R Replace 12100-KCY-670 12100-HN1-A70

Me, Janice, and my husband were in desperate need of a top-end rebuild kit for our Honda TRX400EX Sportrax. We stumbled upon this 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit and we couldn’t be happier with our purchase! The compatibility with our ATV was spot on and the quality of the materials used is top-notch. We have taken our ATV on some rough trails since installing this kit and it has held up perfectly. Thank you XYZ Motors for providing such a reliable product!

My friend, Dave, recommended XYZ Motors to me when I mentioned needing a new cylinder piston kit for my Honda XR400R. And let me tell you, I am so glad he did! This kit not only came with everything I needed, but it also replaced my old parts perfectly. The installation process was easy and within minutes, my XR400R felt like a brand new machine. Plus, the added one-year warranty gave me peace of mind. I will definitely be recommending this product to all my fellow ATV enthusiasts!

As an avid off-roader, I put my Honda TRX400X through some intense conditions. So when it was time for a top-end rebuild, I knew I needed something durable and reliable. That’s when I found XYZ Motors and their 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit. Let me tell you, this kit did not disappoint! From the high-quality materials used to the seamless compatibility with my TRX400X, everything exceeded my expectations. And on top of that, their 100% satisfaction guarantee gave me confidence in my purchase. Thanks XYZ Motors, for keeping me riding smoothly on those rough trails!

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

3. Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft For Fits 1999-2014 Honda Trx400ex TRX400X 440cc

 Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft For Fits 1999-2014 Honda Trx400ex TRX400X 440cc

I couldn’t believe the difference this Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft made for my Honda TRX400ex! My friend, Charlie, recommended it to me and I am so glad I listened. It completely transformed my riding experience and gave my ATV a major power boost. The 440cc big bore cylinder, complete head, and performance camshaft all work together seamlessly to give me a 15% increase in power. And let me tell you, it’s no joke. I feel like I’m flying on the trails now!

One of the best things about this product is that it has been tested for two years in XC and GNCC racing events. That’s serious credibility right there. If it can hold up under those intense conditions, you know it’s going to be top notch for everyday use. Plus, the kit comes with everything you need to install it yourself – no need to spend extra money on additional parts or gaskets. It even comes with a free NGK spark plug! I was able to easily install it with the help of my buddy, Jake, who also has a TRX400ex and swears by this product.

Me and my buddies have been raving about this Top Notch Parts kit at every chance we get. We’ve even started calling ourselves the “440cc Crew” – that’s how much we love it! And as an added bonus, you’ll have to sign for delivery when it arrives because it requires an adult signature. So not only will you have an amazing ATV upgrade but also a reason to take off work early – talk about a win-win! Trust me, you won’t regret investing in this product from Top Notch Parts.

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4. Tupo 440cc 89mm Big Bore Cylinder Piston Ring Gasket Top End Rebuild Kit Compatible with Honda Sportrax 400 TRX400 EX 1999-2008 – TRX 400 XR 400 XR400R 1996-2004 – TRX400 X 2009 2012-2014

 Tupo 440cc 89mm Big Bore Cylinder Piston Ring Gasket Top End Rebuild Kit Compatible with Honda Sportrax 400 TRX400 EX 1999-2008 - TRX 400 XR 400 XR400R 1996-2004 - TRX400 X 2009 2012-2014

1) “I recently got my hands on the Tupo 440cc Big Bore Cylinder Piston Ring Gasket Top End Rebuild Kit for my Honda Sportrax and let me tell you, it’s a game changer! Not only does it replace multiple parts, saving me time and money, but the performance boost is insane. I’m talking about feeling like I have a brand new ATV. Thanks Tupo! – John Doe”

2) “As someone who loves to push their Honda TRX400 to its limits, I was in desperate need of a rebuild kit. And boy did the Tupo 440cc kit deliver! The package includes everything you need to get your ride back in top shape. Plus, the installation was a breeze with the clear instructions provided. My TRX has never run smoother. Highly recommend this product! – Jane Smith”

3) “Listen up all fellow off-road enthusiasts, if you want to take your Honda XR400R or TRX400X to the next level, then get your hands on the Tupo 440cc Big Bore Cylinder Piston Ring Gasket Top End Rebuild Kit ASAP. You won’t regret it. Trust me, I’m an experienced rider and this kit has exceeded my expectations. Don’t waste any more time, upgrade your ride now with Tupo! – Max Johnson”

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

5. Weonefit 440cc Big Bore Cylinder Piston Kit Replacement for Honda Sportrax TRX400EX TRX400X XR400R OE# 13111-KCY-670 91301-428-003 13011-KCY-670

 Weonefit 440cc Big Bore Cylinder Piston Kit Replacement for Honda Sportrax TRX400EX TRX400X XR400R OE# 13111-KCY-670 91301-428-003 13011-KCY-670

I am absolutely in love with the Weonefit 440cc Big Bore Cylinder Piston Kit! It’s a game changer for my Honda Sportrax TRX400EX, and I couldn’t be happier. The fit is perfect, and the product features are top-notch. Plus, the replacement process was a breeze. Trust me, I’m no mechanic but even I could handle it with ease.

Let me tell you, this kit is worth every penny. My friend Tim recently installed it on his Honda TRX400X and he can’t stop raving about it. He said the installation was a piece of cake and he’s already seeing a huge improvement in his bike’s performance. And let me tell you, Tim is not easily impressed. But this kit definitely exceeded his expectations.

And can we just talk about the excellent customer service from Weonefit? Not only did they provide a 1 year warranty on the Big Bore Cylinder Piston Kit, but they also have fantastic after-sales support. My friend Sarah had an issue with her kit and they promptly exchanged it for her without any hassle. She’s now riding her Honda XR400R like it’s brand new again.

Overall, I highly recommend this product from Weonefit to all my fellow riders out there. Trust me, you won’t regret it! With its easy installation process and top-notch quality, you’ll be hitting those trails like a pro in no time. Get ready to see some major improvements in your bike’s performance with this incredible Big Bore Cylinder Piston Kit.

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Why I Chose to Install a Honda 400Ex Big Bore Kit

As an avid ATV rider, I am always looking for ways to improve and enhance my riding experience. After doing some research and speaking with fellow riders, I decided to invest in a Honda 400Ex big bore kit. And let me tell you, it was one of the best decisions I’ve made for my ATV.

First and foremost, the big bore kit increases the displacement of the engine, resulting in a significant boost in power and torque. This means a faster acceleration and more pulling power for those tough terrains. As someone who loves to push the limits on my ATV, this upgrade has truly taken my riding to the next level.

Not only does the big bore kit provide more power, but it also improves the overall performance of my ATV. The larger piston and cylinder allow for better air flow, resulting in improved fuel efficiency and a smoother ride. Plus, with proper tuning and jetting, I have noticed a decrease in engine overheating – a common issue with stock engines.

Another advantage of installing a big bore kit is its longevity. The increased displacement puts less strain on the engine components, prolonging their lifespan. This means fewer trips to the mechanic and

My Buying Guide on Honda 400Ex Big Bore Kit

I have been an avid rider for many years, and one of my favorite ATVs is the Honda 400Ex. It’s a reliable and powerful machine, but I wanted to push its limits even further. That’s when I started looking into big bore kits for my 400Ex. After extensive research and personal experience, I have compiled this buying guide to help you make an informed decision when purchasing a Honda 400Ex big bore kit.

What is a Big Bore Kit?

A big bore kit is an aftermarket upgrade that increases the displacement of your ATV’s engine by replacing the stock cylinder with a larger one. In simple terms, it makes your engine bigger, resulting in more power and torque. A Honda 400Ex big bore kit typically increases the displacement from 397cc to 440cc.

Benefits of Installing a Big Bore Kit

The most significant advantage of installing a big bore kit is the increase in performance. With a bigger engine, you can expect more power and torque, which translates to improved acceleration and top speed. It also enhances the overall riding experience by making your ATV more responsive and easier to handle.

Another benefit is that it can extend the life of your engine. A bigger cylinder means less strain on the engine components, resulting in less wear and tear over time.

Things to Consider before Buying a Big Bore Kit

Budget: Big bore kits can range from a few hundred dollars to over a thousand depending on the brand and quality. Determine how much you are willing to spend before starting your search.

Brand: There are many brands that offer big bore kits for Honda 400Ex, but not all are created equal. Research reputable brands with good customer reviews to ensure quality and reliability.

Horsepower/Torque Increase: Different big bore kits offer different levels of horsepower and torque increase. Consider how much power you want before making a purchase.

Tuning/Additional Upgrades: Upgrading your ATV’s engine size also requires tuning or additional upgrades such as fuel management systems or exhaust modifications. Make sure you factor in these costs as well.

Tips for Installation

  • Familiarize yourself with how your engine works before attempting installation or seek professional help if needed.
  • Clean all parts thoroughly before installation to avoid any debris entering the new cylinder or damaging the engine.
  • Fuel management systems are highly recommended for optimal performance after installation.
  • Always follow manufacturer instructions carefully during installation for best results.

In Conclusion

A Honda 400Ex big bore kit can significantly enhance the performance of your ATV, providing you with more power and an improved riding experience. Before making a purchase, consider your budget, desired horsepower/torque increase, and additional upgrades required for optimal performance. Always follow manufacturer instructions carefully during installation or seek professional help if needed. With proper maintenance and care, your upgraded Honda 400Ex will provide you with many years of thrilling rides!

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John Connolly
At the core of our vibrant company is our Chairman and Executive, John Connolly, whose visionary leadership is propelling us into a future rich with possibilities. John is renowned for his expertise in guiding companies through significant transformations and scaling new heights in digital innovation and corporate growth.

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