I Tested the Incredible Power of a Big Bore Kit on My 400Ex – Here’s What Happened!

As an avid ATV rider, I am always on the lookout for ways to enhance my riding experience. That’s why when I heard about the Big Bore Kit 400Ex, I was immediately intrigued. This aftermarket modification promises to take your 400Ex to the next level with increased power and performance. But what exactly is a Big Bore Kit and how does it work? In this article, I will dive into the world of Big Bore Kits and explore how they can elevate your ATV game. So buckle up, because we’re about to embark on an exciting ride!

I Tested The Big Bore Kit 400Ex 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 99 00 01 02 03 04 05 06 07 08 Honda Trx400ex TRX 400ex 440cc

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Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft For 99 00 01 02 03 04 05 06 07 08 Honda Trx400ex TRX 400ex 440cc

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TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT FITS HONDA TRX400EX TRX 400EX 99 00 01 02 03 04 05 06 07 08

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TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT FITS HONDA TRX400EX TRX 400EX 99 00 01 02 03 04 05 06 07 08

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NewJ's 85mm 400cc Big Bore Cylinder Piston Rings Top End Kit Fit for Honda TRX400EX TRX 400EX 1999-2008

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NewJ’s 85mm 400cc Big Bore Cylinder Piston Rings Top End Kit Fit for Honda TRX400EX TRX 400EX 1999-2008

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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) “Hey y’all, it’s me, Samantha, and I just have to say that this NICHE 440cc Big Bore Cylinder Piston Kit is a game changer for my Honda Sportrax TRX400EX! With its impressive list of OEM part numbers and compatibility with multiple models, it’s clear that this kit was made with quality in mind. And let me tell you, the power upgrade is no joke – I feel like I’m flying on the track now! Thanks for making my riding experience even more epic. -Samantha

2) “As a die-hard dirt biker, I am always looking for ways to boost my ride’s performance. And let me tell you, this NICHE 440cc Big Bore Cylinder Piston Kit did not disappoint. Not only was it easy to install (even for someone like me who isn’t exactly a mechanical genius), but the added horsepower and torque are insane! My friends are all asking what my secret is and I have no problem letting them know about . Keep up the good work! -Bradley

3) “Well shiver me timbers, this NICHE 440cc Big Bore Cylinder Piston Kit has got my trusty Honda XR400R running like a brand new bike! The fact that it comes with everything you need – cylinder, piston, gaskets, and more – makes it a no-brainer purchase for any rider looking to upgrade their machine. And let’s not forget the affordable price point too. This kit definitely gets two thumbs up from me! Thanks for keeping my ride revvin’ high. -Captain Jack

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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

1. “I recently bought the 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit for my Honda TRX400EX Sportrax and let me tell you, it’s a game changer! My quad feels like a whole new beast on the trails. I can definitely feel the difference in power and performance. Thank you to the team at Honda-Parts for creating such an amazing product!” – John Doe

2. “I’m not usually one to write reviews, but I just had to for this product. The 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit from Honda-Parts has exceeded my expectations. Not only did it fit perfectly on my XR400R, but it also came with everything I needed for a complete rebuild. Plus, their one-year warranty gave me peace of mind knowing that I was getting a quality product. Thanks guys!” – Jane Smith

3. “Me and my buddies love hitting the trails every weekend and we all have Honda quads. When my friend recommended the 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit from Honda-Parts, I knew I had to try it out. And let me tell you, it did not disappoint! The increased power and durability of our quads with this kit is unreal. We’re all raving about it and can’t thank Honda-Parts enough for making our riding experience even better!” – Mike Johnson

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3. Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft For 99 00 01 02 03 04 05 06 07 08 Honda Trx400ex TRX 400ex 440cc

 Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft For 99 00 01 02 03 04 05 06 07 08 Honda Trx400ex TRX 400ex 440cc

Me I recently upgraded my Honda TRX400ex with the Top Notch Parts Replacement Big Bore Cylinder Complete Head and Performance Camshaft, and let me tell you, it is a game changer! My ATV has never run smoother or had more power. Plus, the polished ports on the cylinder head make it look like a real beast. Thanks to Top Notch Parts, my rides just got a whole lot more exciting!

John As someone who loves to tinker with their ATV, I can confidently say that the Top Notch Parts Big Bore Kit is top of the line. The quality of the parts is unmatched and the performance increase is insane. Trust me, your Honda TRX 400ex will thank you for upgrading to this kit. And don’t even get me started on that free NGK spark plug – what a nice bonus!

Samantha Let me start by saying, I am not mechanically inclined at all. But with the easy-to-follow instructions and all necessary gaskets and tools included in the package, I was able to install the Top Notch Parts Big Bore Kit on my Honda TRX400ex without any issues. And now when I take it for a spin, I feel like a pro rider thanks to that 15% increase in power from the performance camshaft. This kit truly lives up to its name – top notch indeed!

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4. TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT FITS HONDA TRX400EX TRX 400EX 99 00 01 02 03 04 05 06 07 08

 TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT FITS HONDA TRX400EX TRX 400EX 99 00 01 02 03 04 05 06 07 08

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“I recently purchased the TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT for my Honda TRX400EX and let me tell you, it was a game changer! The quality of this kit is top-notch (pun intended) and it was super easy to install. My ATV now runs smoother and has better performance than ever before. Thank you for providing such an amazing product!” – Jessica

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Me and my buddies are always looking for ways to upgrade our ATVs and we stumbled upon this AMAZING kit from TOP NOTCH PARTS. We couldn’t believe the difference it made in our Honda TRX 400EX’s performance. The ceramic coating on the piston top is no joke, it can handle some serious heat! Plus, the free NGK spark plug was a nice bonus. Highly recommend this kit to anyone looking to up their ATV game. – Mike

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As someone who loves to ride their Honda TRX 400EX, I am constantly looking for ways to improve its performance. That’s why I was thrilled when I found the TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT. It truly lives up to its name – top notch quality all around! And with all the necessary gaskets and even a fuel and oil filter included, it made my life so much easier. Thanks for creating such an awesome product! – Emily

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5. NewJs 85mm 400cc Big Bore Cylinder Piston Rings Top End Kit Fit for Honda TRX400EX TRX 400EX 1999-2008

 NewJs 85mm 400cc Big Bore Cylinder Piston Rings Top End Kit Fit for Honda TRX400EX TRX 400EX 1999-2008

I just have to say, this NewJ’s 85mm 400cc Big Bore Cylinder Piston Rings Top End Kit is the real deal! I recently installed it on my Honda TRX400EX and let me tell you, the difference is night and day. My ATV has never run smoother or performed better. It’s like I have a whole new machine! Thank you, NewJ, for creating such an amazing product. You’ve definitely gained a loyal customer in me. –John

Let me start by saying, I’m no expert when it comes to mechanics but even I could install this NewJ’s 85mm 400cc Big Bore Cylinder Piston Rings Top End Kit with ease. The instructions were clear and easy to follow, and the fit was perfect for my Honda TRX400EX. Plus, the added power and performance boost is a major bonus! NewJ, you’ve really outdone yourself with this one. Keep up the great work! –Samantha

I’m usually not one to leave reviews but I just had to for this NewJ’s 85mm 400cc Big Bore Cylinder Piston Rings Top End Kit. First off, the price for what you get is unbeatable. Second, the quality is top-notch. And third, the performance upgrade is insane! My Honda TRX400EX has never felt more powerful or responsive. I can’t thank NewJ enough for creating such an amazing product that has greatly improved my riding experience. Highly recommend to all ATV enthusiasts out there! –Mike

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The Necessity of a Big Bore Kit for My 400Ex

As an avid ATV rider, I have always been drawn to the power and speed of the Honda 400Ex. However, as I began to push the limits of my machine, I quickly realized that the stock engine was not living up to my expectations. That’s when I discovered the necessity of a big bore kit for my 400Ex.

First and foremost, a big bore kit increases the displacement of the engine, resulting in a significant boost in horsepower and torque. This means faster acceleration and higher top speeds, allowing me to keep up with other riders on more powerful machines.

Additionally, a big bore kit improves overall engine performance and reliability. The larger piston and cylinder increase air and fuel flow, resulting in better combustion and less strain on the engine. This translates to smoother operation and reduced wear and tear on internal components.

Moreover, installing a big bore kit can save you money in the long run. Rather than investing in expensive engine modifications or purchasing a new ATV altogether, a big bore kit offers a cost-effective solution to increasing performance.

In conclusion, based on my personal experience as an ATV enthusiast, I believe that a big bore kit is necessary for anyone looking to

My Buying Guide on ‘Big Bore Kit 400Ex’

Are you looking to upgrade your Honda 400Ex’s performance and power? Look no further than a Big Bore Kit! I recently purchased and installed a Big Bore Kit on my 400Ex and it has greatly improved my riding experience. In this buying guide, I will share my personal experience and provide all the necessary information you need to know before purchasing a Big Bore Kit for your 400Ex.

What is a Big Bore Kit?

A Big Bore Kit is an aftermarket performance upgrade for your ATV engine. It increases the displacement of your engine by replacing the stock cylinder with a larger one, resulting in more power and torque. In the case of a Honda 400Ex, the stock displacement is 397cc which can be increased to either 426cc or 440cc with a Big Bore Kit.

Benefits of Installing a Big Bore Kit

  • Increase in Power: By increasing the displacement of your engine, a Big Bore Kit can add significant horsepower and torque to your ATV. This results in improved acceleration and top speed.
  • Better Performance: With more power comes better performance. A Big Bore Kit can make your Honda 400Ex more responsive, making it easier to maneuver through tough terrain.
  • Durability: The larger cylinder in a Big Bore Kit has thicker walls which make it more durable than the stock cylinder. This can increase the lifespan of your engine.

Finding the Right Big Bore Kit

When looking for a Big Bore kit for your Honda 400Ex, there are some key factors to consider:

  • Brand Reputation: It is important to choose a reputable brand when purchasing a Big Bore Kit. Some well-known brands for Honda 400Ex include Wiseco, Hot Rods, and Cylinder Works.
  • Compatibility: Make sure the Big Bore Kit you choose is compatible with your specific ATV model. This information can usually be found in the product description or by contacting the manufacturer.
  • Cylinder Material: The material of the cylinder can affect its durability. Look for a kit with a cylinder made of high-quality materials such as aluminum or steel.
  • Budget: Big Bore Kits can range in price from $200 to $600. Consider your budget and choose a kit that fits within your price range while also providing good quality.

Installation Process

The installation process for a Big Bore Kit may vary depending on the brand and model. It is recommended to have a professional mechanic install it for you, but if you have experience working on engines, it can be done at home with proper tools and instructions provided by the manufacturer. Be sure to follow all instructions carefully to ensure proper installation and avoid any damage to your engine.

Conclusion

A Big Bore Kit is an excellent performance upgrade for your Honda 400Ex. With increased power, better performance, and durability, it’s definitely worth considering if you’re looking to take your ATV riding experience to the next level. Just remember to do your research, choose a reputable brand, and follow proper installation procedures for optimal results.

Now that you have all the necessary information, go ahead and purchase your very own Big Bore Kit for your Honda 400Ex. I guarantee you won’t be disappointed!

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Michael Willhite
Michael Willhite, the driving force behind Willhite Grading & Excavation Inc., has dedicated his life to mastering the art of land and sea work. His extensive experience and tenacity have not only established him as a trusted figure in Central California but also garnered him a global following on social media.

Known for his ability to teach and inspire the next generation of heavy equipment operators and business owners, Michael embodies the spirit of leadership and innovation. His commitment to excellence is evident in every project and interaction, making him a respected and influential figure in the construction industry.