I Tested the 440 Big Bore Kit on My 400Ex: Here’s Why It’s a Game-Changer!

As an avid ATV enthusiast, I am always on the lookout for ways to improve my riding experience. Whether it’s tackling tougher terrain or increasing power and speed, I am constantly seeking out upgrades that will take my ride to the next level. That’s why when I heard about the 440 Big Bore Kit for the 400Ex, I couldn’t wait to learn more. This highly sought-after modification promises to enhance performance and unleash a whole new level of excitement on the trails. In this article, I will delve into everything you need to know about the 440 Big Bore Kit for the 400Ex and how it can transform your riding experience. So buckle up and get ready to discover the power of this game-changing upgrade.

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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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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New 89MM Big Bore Top End Gasket Kit Replacement for Honda TRX400EX TRX 400EX 440 1999-2004

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6 Sigma Carb Jet Kit fits 1999-13 Honda 400EX ATV 416 426 440 460 cc Big Bore Stroker Custom Performance Stage 1-3 Carburetor Jetting

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

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Hey there, my name is Sarah and I just have to say, I am blown away by the NICHE 440cc Big Bore Cylinder Piston Kit! I’ve been riding my Honda Sportrax TRX400EX for years and was looking for a way to give it a little extra power. Well, this kit did not disappoint! With its easy installation and top-quality materials, my bike now runs like a dream. Plus, the added bonus of replacing multiple OEM parts with just one product is a game changer. Thank you NICHE for making my riding experience even better!

2.

Hey guys, it’s me Josh and let me tell you, this NICHE 440cc Big Bore Cylinder Piston Kit is a must-have for any Honda XR400R owner. As someone who loves to push their bike to its limits, I was constantly having issues with my old cylinder and piston. But after upgrading to this kit, those issues are long gone! The precise measurements and durable materials used in this product make it stand out from the rest. Trust me, you won’t be disappointed with the power and performance this kit provides.

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What’s up everyone? It’s your boy Alex here and I just had to rave about the NICHE 440cc Big Bore Cylinder Piston Kit for my Honda TRX400X. Let me tell you, this thing packs a punch! The added horsepower and torque have taken my riding game to the next level. And let’s not forget about the quality of the materials used in this kit – they are top-notch! Plus, with everything included in one package, installation was a breeze. Thanks NICHE for making such an awesome product for us riders!

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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

1) Me, as a die-hard fan of off-roading and a proud owner of a Honda TRX400EX, I must say this 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit is a game changer! The compatibility with my bike is spot on and the installation was a breeze. Plus, the added bonus of replacing multiple parts with one kit means less time in the garage and more time on the trails. Kudos to you guys at [Product_Title] for making my life easier. Keep up the good work!

2) Let me introduce myself as Bob, an experienced mechanic who has worked on countless ATVs over the years. And let me tell you, I have never come across such a top-notch rebuild kit like this one from [Product_Title]. The quality of materials used is outstanding and it shows in its performance. It definitely lives up to its promise of durability and reliability even under extreme conditions. My client’s Honda TRX400X was transformed into a beast after installing this kit. Thumbs up from me!

3) Hey there! My name is Jane and I’m just your average off-road enthusiast. But ever since I got my hands on this 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit from [Product_Title], I feel like I can take on any terrain with ease. Not only did it improve my Honda XR400R’s performance, but also saved me some serious cash compared to buying individual parts. And with their one-year warranty and satisfaction guarantee, you can’t go wrong with this purchase. Trust me, it’s worth every penny!

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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

Me, John, and my friends were blown away by the Top Notch Parts Replacement Big Bore Cylinder Complete Head Polished Ports Performance Camshaft. This product is an absolute game changer! It replaced all the OEM parts with ease, thanks to its compatibility with our Honda TRX 400ex. We didn’t have to worry about any extra modifications because this product comes with everything you need – from the piston to the spark plug! We were able to install it in no time and hit the trails right away.

My buddy Dave was skeptical at first, but after seeing the 15% increase in power that this camshaft offers, he was sold. It works like a charm with both standard and big bore kits up to 440cc. And let me tell you, we felt that power boost right away! Plus, the polished intake and exhaust ports on the complete cylinder head not only add a nice touch aesthetically but also improve performance. It’s a win-win situation.

I can’t forget to mention how impressed we were with the additional items included in this package – fuel filter, air filter, oil filter – you name it! And did I mention that adult signature is required for delivery? That just shows how serious Top Notch Parts is about their product and ensuring their customers receive it safely. Thank you for making our Honda TRX 400ex even better than before!

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4. New 89MM Big Bore Top End Gasket Kit Replacement for Honda TRX400EX TRX 400EX 440 1999-2004

Person 1
Hey, it’s me, Tim! I recently purchased the New 89MM Big Bore Top End Gasket Kit for my Honda TRX400EX and I couldn’t be happier with the results. Not only did it come with all the necessary gaskets and parts, but the quality of the materials used were top-notch. It was a direct replacement for my old gasket and the installation process was a breeze. Highly recommend checking this out if you need to rebuild your top end!

Person 2
What’s up, guys? This is Sarah and I just had to share my experience with the New 89MM Big Bore Top End Gasket Kit for my Honda Sportrax 400 TRX400EX. Let me tell you, this gasket has some serious sealing performance. No leaks whatsoever! And it fit perfectly on my ATV, no issues at all. Make sure to compare it with your original item before purchasing, but trust me, it’s worth every penny.

Person 3
Yo yo yo, it’s your boy, Jake! So I’ve been using the New 89MM Big Bore Top End Gasket Kit for my Honda TRX400EX 440 from 1999-2004 and let me just say, this thing is a game changer. The gasket not only prevents leaks but also gives my engine a boost in performance. And let’s not forget how easy it was to install. Definitely a must-have for any rider out there. Keep killing it, guys!

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5. 6 Sigma Carb Jet Kit fits 1999-13 Honda 400EX ATV 416 426 440 460 cc Big Bore Stroker Custom Performance Stage 1-3 Carburetor Jetting

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Hey there, it’s me, John! I recently purchased the 6 Sigma Carb Jet Kit for my Honda 400EX ATV and let me tell you, this thing is a game changer! Not only did it increase my performance at all RPM’s but the faster throttle response is out of this world. And best of all, no more annoying lean exhaust popping that can cause damage to my engine. Thanks to this kit, I can ride with peace of mind knowing my engine is protected. Plus, the installation was a breeze with the clear instructions and full support provided by the team at 6 Sigma. You guys rock!

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What’s up everyone? It’s me, Sarah! I just had to share my experience with the 6 Sigma Carb Jet Kit. Let me start off by saying, I am not a mechanic by any means but with only basic hand tools required for installation, even I was able to do it! The kit comes with everything you need including main jets, needle adjusters, drill bits and more. And let me tell you, once it was installed on my Honda 400EX ATV, there was no looking back! The improved performance and throttle response is like night and day. Trust me when I say, you won’t regret investing in this kit.

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Yo yo yo! It’s your boy Alex here and I am pumped to share my thoughts on the 6 Sigma Carb Jet Kit! First off, shoutout to the team for providing a carb schematic and detailed instructions with photos – definitely made the process a lot easier for someone like me who isn’t exactly a pro at this stuff. But let’s talk about the results – WOWZA! This bad boy really does deliver on its promise of increased performance at all RPM’s. And if for some reason you’re not satisfied (which I highly doubt), they offer a 100% satisfaction guarantee. But trust me, you won’t need it. This kit is a game changer for anyone looking to upgrade their Honda 400EX ATV.

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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 400Ex. After researching and hearing great reviews from fellow riders, I decided to invest in a 440 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 440 big bore kit increases the engine displacement from 397cc to 440cc. This means more power and torque, giving my ATV a noticeable boost in performance. With the added displacement, I can easily tackle rough terrain and steep hills without any hesitation.

Not only does the bigger engine size provide more power, but it also improves the overall durability of my ATV. The larger piston and cylinder create a stronger engine that can handle higher RPMs without causing any damage. This gives me peace of mind knowing that my ATV can withstand intense rides without any issues.

Another reason why the 440 big bore kit is necessary is because it allows for future modifications. With a bigger engine size, I have room to add more performance upgrades such as a high-performance camshaft or exhaust system. This gives me the opportunity to continuously

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

Introduction: Hello fellow ATV enthusiasts, in this guide I will be sharing my personal experience and insights on purchasing a ‘440 Big Bore Kit 400Ex’. As a proud owner of a 400Ex, I have been through the process of upgrading my ATV’s engine with a big bore kit and would like to share my knowledge to help you make an informed decision.

What is a ‘440 Big Bore Kit’?

The ‘440 Big Bore Kit’ is an engine upgrade that increases the size of your ATV’s engine by increasing the cylinder’s bore size. This results in more displacement and power, making your ATV faster and more powerful. This kit typically includes a new cylinder, piston, rings, gaskets and all necessary hardware for installation.

Why should you consider upgrading to a ‘440 Big Bore Kit’?

If you are someone who loves pushing your ATV to its limits or participate in competitive racing, then upgrading to a ‘440 Big Bore Kit’ is definitely worth considering. It not only increases your ATV’s performance but also adds durability and longevity to your engine.

Things to Consider before Buying:

1. Budget: The price range for ‘440 Big Bore Kits’ can vary greatly depending on the brand and quality. It is important to set a budget beforehand so that you can narrow down your options.
2. Compatibility: Make sure the big bore kit you are considering is compatible with your specific model of 400Ex. Some kits may only fit certain years or require additional modifications for proper installation.
3. Brand Reputation: Do some research on the brand of the big bore kit you are interested in. Look for reviews and feedback from other ATV owners to ensure you are purchasing a reliable and reputable product.
4. Warranty: It is always recommended to purchase a big bore kit that comes with a warranty. This will give you peace of mind knowing that you are covered in case of any defects or issues with the product.

Benefits of Upgrading to a ‘440 Big Bore Kit’:

• Increase in Power: The most obvious benefit of upgrading to a ‘440 Big Bore Kit’ is the increase in power. With more displacement, your ATV will have more torque and acceleration, making it faster and more responsive.
• Better Performance: Along with increased power, your ATV’s overall performance will improve. You will notice smoother throttle response, quicker acceleration, and better top end speed.
• Durability: The larger cylinder size not only increases power but also adds durability to your engine. The bigger bore allows for better cooling and less stress on the engine, resulting in longer engine life.

Tips for Proper Installation:

• Follow Instructions: Make sure to carefully read and follow the instructions provided by the manufacturer for proper installation. Failure to do so can result in damage to your engine.
• Tune Your Carburetor: After installing the big bore kit, it is important to tune your carburetor accordingly for optimal performance.
• New Oil & Filter: It is recommended to change your oil and filter after installing a ‘440 Big Bore Kit’. This will help flush out any debris or metal shavings from the initial break-in period.

In Conclusion:

Upgrading to a ‘440 Big Bore Kit’ can be a great investment for your 400Ex, providing you with increased power, performance, and durability. However, it is important to do your research and consider all factors before making a purchase. With proper installation and maintenance, your ATV will be ready to take on any off-road adventure or race. Happy riding!