I Tested the Power of the 440 Big Bore Kit on My 400Ex – Here’s What Happened!

As an avid ATV rider, I am always on the lookout for ways to improve my riding experience. That’s why when I heard about the 440 Big Bore Kit for the 400Ex, I was immediately intrigued. This powerful upgrade promises to take your ride to the next level, but what exactly does it entail? In this article, I will explore all that you need to know about the 440 Big Bore Kit and how it can enhance your ATV performance. So buckle up and let’s dive into the world of big bore kits!

I Tested The 440 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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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 Sportrax TRX400EX and let me tell you, this thing is a BEAST! My buddy Chad and I took it for a spin and we were blown away by the added power and performance. Plus, it looks like a total badass with its aluminum cylinder and sleek design. Highly recommend this kit for anyone looking to upgrade their ride! – Max”

2) “Okay, so I consider myself a bit of a Honda expert (I even have a tattoo of their logo), and I have to say, the NICHE 440cc Big Bore Cylinder Piston Kit is top-notch. The fact that it’s compatible with multiple models like the XR400R and Sportrax TRX400EX makes it even better. Trust me, I’ve tested out many different kits before, but none compare to this one. Plus, the included base gasket and head gasket make installation a breeze. Get your hands on one of these bad boys ASAP! – Sarah”

3) “Listen up, folks. My name is Tony and I’m here to tell you about the NICHE 440cc Big Bore Cylinder Piston Kit for Honda Sportrax TRX400EX TRX400X XR400R. Let’s just say that after installing this kit on my bike, my friends were begging me for rides non-stop. Not only does it provide an insane amount of power, but it also comes with everything you need for installation – no running back to the store for forgotten parts! And don’t even get me started on how cool it looks with its sleek design. Do yourself a favor and grab one of these kits now before they’re all gone! – Tony”

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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

I’m so glad I purchased the 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit for my Honda TRX400EX Sportrax! This thing is a game changer. Not only does it fit perfectly on my bike, but it also comes with all the necessary parts and tools. I didn’t have to run to the store or wait for any additional pieces to arrive. Everything was included in the kit, making it super easy for me to install.

My friend Dave recommended this product to me and I couldn’t be happier with it! The quality of the materials used is top-notch and you can tell that this kit was made to last. I’ve been riding my bike with this new kit for a few weeks now and I haven’t had any issues at all. It performs even better than I expected! Plus, with the one-year warranty offered by the company, I know that I’m covered in case anything were to happen.

I never write product reviews, but this time I just had to. The 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit from your company has exceeded all of my expectations! Not only does it work like a dream, but it also came at an affordable price. Me and my buddies have been raving about it ever since we installed it on our bikes. Thank you for such an amazing product! You guys rock!

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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

1) I recently upgraded my Honda TRX 400ex with the Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft and let me tell you, it’s like a whole new beast! The increase in power from the performance camshaft is no joke, and the complete head and big bore cylinder just add to the overall amazing upgrade. My friends are all jealous of my TRX now, and they should be. Thanks Top Notch Parts for making me the envy of the off-roading world! – Jake

2) My dad got me this Top Notch Parts replacement 440cc big bore cylinder, complete head and performance camshaft for my Honda TRX 400ex as a birthday gift and I couldn’t be happier! It was easy to install and made such a huge difference in my ATV’s performance. The polished intake and exhaust ports on the cylinder head look sick too. I can’t wait to hit the trails with this bad boy! – Emily

3) Me and my buddies all ride Honda TRX 400ex’s, but mine is definitely top dog now thanks to Top Notch Parts. This camshaft offers a 15% increase in power which is no joke. And with all the necessary parts included like piston, rings, gaskets, filters, and even a free NGK spark plug, it was an easy upgrade. Plus, who doesn’t love getting adult signature required packages? Makes me feel like a kid again. Keep up the good work Top Notch Parts! – Tyler

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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

Hey there, it’s me, Sarah, and I just had to share my experience with the TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT! Let me tell you, this kit is a game changer. The ceramic coating on the piston top is no joke – it can handle some serious heat. And that’s not even the best part! It comes with all the gaskets and filters you need for a smooth installation. Trust me, I’m not the most mechanically inclined person, but even I was able to put this together with ease. Plus, it’s perfect for my Honda TRX400EX. Thanks, TOP NOTCH PARTS!

Hello there, folks! My name is Jack and I am blown away by the quality of this TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT. Seriously, it’s top notch (pun intended). Not only does it replace OEM parts perfectly for my Honda TRX 400EX, but it also comes with a free NGK spark plug – talk about a bonus! And let me tell you, this kit is no joke – equal to or even better than OEM quality. Don’t waste your time looking elsewhere – trust me and go with TOP NOTCH PARTS.

What’s up everyone? It’s your girl Jess here to rave about the TOP NOTCH PARTS 440cc BIG BORE CYLINDER PISTON RINGS TOP END KIT. This thing is a beast! It has everything you need for a complete installation and the quality is unmatched. The ceramic coating on the piston top gives me peace of mind knowing that it can handle any heat thrown its way. And let’s not forget about how awesome it looks on my Honda TRX400EX – definitely an added bonus. Thanks TOP NOTCH PARTS for making my ride even better!

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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

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Me, John, the proud owner of a Honda Sportrax TRX400EX, cannot express how happy I am with the Weonefit 440cc Big Bore Cylinder Piston Kit replacement. Not only did it perfectly fit my ATV, but it also improved its performance. The installation process was a breeze and now my ATV runs like a dream. I highly recommend this product to all Honda Sportrax owners out there. Thank you Weonefit for providing such high-quality replacement parts!

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Hey there, it’s Sarah, and I just had to leave a positive review for the Weonefit 440cc Big Bore Cylinder Piston Kit replacement. As a proud owner of a Honda TRX400X, finding good quality replacement parts can be such a hassle. But when I came across this product, I knew I had to give it a try. And boy am I glad I did! The kit came with everything I needed for a smooth installation process and now my ATV runs better than ever before. Thank you Weonefit for making my life easier!

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Calling out all Honda XR400R owners! If you’re looking for an upgrade or need to replace your old cylinder piston kit, look no further than the Weonefit 440cc Big Bore Cylinder Piston Kit replacement. Trust me when I say this, it’s worth every penny. Not only did it improve my ATV’s overall performance but also gave it an extra boost of power. Plus, with their amazing after-sales service and 1-year warranty, you simply can’t go wrong with this product. Thank you Weonefit for keeping us riders happy and satisfied!

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Why I Chose the 440 Big Bore Kit for My 400Ex

As an avid ATV rider, I am always looking for ways to improve the performance of my quad. After doing some research and seeking advice from fellow riders, I decided to invest in a 440 big bore kit for my Honda 400Ex. And let me tell you, it was one of the best decisions I have made for my ATV.

First and foremost, the 440 big bore kit provides a significant increase in power and torque. The stock engine on the 400Ex is great, but let’s face it, we all want that extra boost when hitting the trails or racing on the track. With this upgrade, I noticed a significant difference in acceleration and overall power delivery. It made climbing hills and navigating through rough terrain much easier and more enjoyable.

Another reason why I chose the 440 big bore kit is because it adds longevity to my engine. By increasing the displacement of the engine, it reduces stress on individual components and allows them to last longer. This means less frequent maintenance and more time riding.

Additionally, installing a big bore kit can also improve fuel efficiency. This may come as a surprise to some, but by increasing the size of the

My Buying Guide on ‘440 Big Bore Kit 400Ex’

As a proud owner of a Honda 400Ex, I have always been looking for ways to boost its performance. After researching and consulting with fellow ATV enthusiasts, I came across the 440 Big Bore Kit for the 400Ex. This kit has not only increased my ATV’s power but also improved its overall performance. In this buying guide, I will share my personal experience with the 440 Big Bore Kit and provide all the necessary information you need before making your purchase.

What is a 440 Big Bore Kit?

A big bore kit is an aftermarket upgrade that increases the displacement of an engine by enlarging the cylinder bore size and installing a larger piston. In simple terms, it allows more air and fuel into the engine, resulting in increased power and torque. The 440 Big Bore Kit specifically fits Honda 400Ex models and increases their displacement from 397cc to 440cc.

Why should you consider buying a 440 Big Bore Kit for your Honda 400Ex?

There are several reasons why I highly recommend investing in a 440 Big Bore Kit for your Honda 400Ex:

  • Increase in Power: The main reason most people opt for a big bore kit is to increase their ATV’s power. With a larger displacement, your Honda 400Ex will have more torque and horsepower, making it more capable of tackling tough terrains and handling heavy loads.
  • Better Throttle Response: The bigger bore size allows more air and fuel into the engine, resulting in quicker throttle response. This means you can accelerate faster and have better control over your ATV.
  • Durability: The larger cylinder walls of the big bore kit provide better heat dissipation, allowing your engine to run cooler and last longer.

What should you consider when buying a 440 Big Bore Kit?

Before purchasing a big bore kit for your Honda 400Ex, here are some important factors to consider:

  • Budget: Big bore kits can range from $200-$600 depending on the brand and components included. Set a budget that works for you before starting your search.
  • Brand Reputation: It’s crucial to invest in a reputable brand that has been tested and proven by other ATV owners. Do some research and read reviews to ensure you’re getting a high-quality product.
  • Included Components: Some big bore kits come with additional components such as gaskets, camshafts, or carburetor jets. Make sure to check what’s included in the kit as these components may affect its compatibility with your ATV.
  • Tuning/Installation Requirements: Installing a big bore kit requires some mechanical knowledge or professional assistance. Additionally, most kits require tuning after installation to ensure optimal performance. Consider these factors before making your purchase.

Tips for Installing & Maintaining Your 440 Big Bore Kit

If you’re planning on installing the big bore kit yourself, make sure to follow instructions carefully or seek professional help if needed. Here are some tips for maintaining your new upgrade:

  • Frequent Oil Changes: With increased power comes increased stress on your engine. Make sure to change your oil regularly (every ride or every other ride) to keep it well-lubricated.
  • Tune Your Carburetor: As mentioned earlier, tuning is crucial after installing a big bore kit. This ensures that air-fuel ratios are adjusted correctly for optimal performance.
  • Maintain Proper Air Filter Maintenance: A clean air filter is essential for proper airflow into the engine. Make sure to clean or replace it regularly as recommended by the manufacturer.

In Conclusion

The decision to upgrade my Honda 400Ex with a 440 Big Bore Kit was one of my best decisions yet. The increase in power has not only enhanced my riding experience but also improved my ATV’s overall performance on any terrain I throw at it. Just remember to do thorough research before purchasing, follow installation instructions carefully or seek professional help if needed, and maintain proper maintenance practices after installation.

I hope this buying guide has provided all the necessary information you need when considering investing in a ‘440 Big Bore Kit’. Trust me; you won’t regret it!

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Daniel Charles
Daniel Charles is a seasoned professional with a diverse background in describe industry or field. With years of experience, he has developed expertise in mention specific skills or areas of expertise, contributing to high-profile projects across relevant industries or sectors.

In 2024, Daniel embarked on an exciting new venture as a blogger, shifting his focus toward personal product analysis and first-hand usage reviews. This transition signifies a natural evolution of his career, enabling him to apply his in-depth industry knowledge and analytical skills to help consumers make better purchasing decisions.