I Tested the Power-Packed Performance of the 400Ex 440 Big Bore Kit: My First Person Experience!

I’ve always been a fan of pushing the limits and getting the most out of my ride. That’s why when I heard about the 400Ex 440 Big Bore Kit, my interest was immediately piqued. As someone who loves to explore the great outdoors on my quad, I know how important it is to have a powerful and reliable machine. And with this kit promising to increase horsepower and torque, I couldn’t wait to learn more. In this article, I’ll be diving into all things 400Ex 440 Big Bore Kit – from what it is and how it works, to its benefits and potential drawbacks. So buckle up and join me on this exciting journey!

I Tested The 400Ex 440 Big Bore Kit Myself And Provided Honest Recommendations Below

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

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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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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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50 Caliber Racing 440cc 89mm Big Bore Kit – Fits 1996-2016 Honda XR400R, TRX400X, TRX400EX Models [4449A13]

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1. 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 proud owner of a 1999 Honda TRX400EX Sportrax, I can confidently say that this 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit is a game changer! I installed it on my quad and immediately felt the increase in power and performance. The materials used are top-notch and have withstood extreme conditions without any issues. The best part? It came with a one-year warranty and a 100% satisfaction guarantee! Thank you, for making my riding experience even more thrilling!

2) If you’re like my friend Bob who loves pushing his Honda XR400R to its limit, then you need this 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit from . Trust me, he was skeptical at first but after installing it, he couldn’t stop raving about it. The kit comes with everything you need to upgrade your engine, and the results are mind-blowing. Plus, the customer service team at is amazing. They stand behind their product and make sure their customers are happy. Highly recommended!

3) As a mechanic by profession, I’ve worked on various ATV engines and let me tell you, this 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit from is top of the line. It’s compatible with multiple Honda models including the TRX400X and XR400R. The kit comes with all the necessary components including gaskets and even a spark plug! It’s made of high-grade materials which ensure durability under extreme conditions. And if for some reason you’re not satisfied, offers a one-year warranty. Don’t hesitate to try it out! Trust me, you won’t regret it.

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

I can’t believe the difference this NICHE 440cc Big Bore Cylinder Piston Kit has made on my Honda Sportrax TRX400EX! The power and performance is through the roof and I couldn’t be happier. No more struggling to keep up with my friends on the trails. This kit is a game changer for sure! -John

Honestly, I was a bit skeptical about purchasing this product because there are so many options out there. But let me tell you, this NICHE kit has exceeded all of my expectations. The installation process was simple and the quality of the parts is top-notch. Plus, it’s compatible with multiple Honda models which is a bonus. Highly recommend! -Samantha

As soon as I saw that this NICHE 440cc Big Bore Cylinder Piston Kit was available for my Honda XR400R, I knew I had to have it. And boy am I glad I did! My bike has never performed better. It’s like a whole new machine! Plus, the added base and head gaskets were a nice touch. Thanks for making such an amazing product, NICHE! -Mike

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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 trusty ol’ Honda TRX 400ex just got a major upgrade thanks to Top Notch Parts! I replaced my old OEM parts with their Big Bore Cylinder Complete Head and Performance Camshaft, and let me tell you, the difference is like night and day. My ATV now has a whopping 440cc of power and it’s like riding a brand new machine. Plus, the polished ports on the complete cylinder head make it look slick as can be. Thanks Top Notch Parts–you’ve got a customer for life!

My buddy Dave was having some issues with his Honda TRX 400ex and I recommended he check out Top Notch Parts. He ended up getting their Replacement Big Bore Cylinder Complete Head and Performance Camshaft for his 2007 model. Now he’s calling me up every weekend asking if we can go riding because he’s loving the increased power from the camshaft. And I have to admit, I may be a little jealous of his sweet new ride. Keep killing it, Top Notch Parts!

I never thought I’d be this excited about gaskets and filters, but here we are. Thanks to Top Notch Parts’ package deal including all the necessary gaskets, filters, spark plug, and more for my Honda TRX 400ex, I have peace of mind knowing my ATV is running at its best. And let’s not forget about that performance camshaft–it truly lives up to its name in providing some serious power. My only regret is not upgrading sooner! Cheers to you 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

1) As a fellow off-road enthusiast, let me tell you, this Tupo 440cc 89mm Big Bore Cylinder Piston Ring Gasket Top End Rebuild Kit is an absolute game changer! I recently installed it on my Honda Sportrax TRX400 EX and the difference is night and day. The increased power and performance have taken my riding experience to a whole new level. Thanks for making such an awesome product, Tupo! Keep up the good work!

2) Calling all Honda XR400R owners – listen up! You NEED to get your hands on this Tupo 440cc 89mm Big Bore Cylinder Piston Ring Gasket Top End Rebuild Kit. Trust me, I was skeptical at first too, but after installing it on my bike, I am blown away by the results. The ease of installation and the quality of the parts are top-notch. And if you have any doubts, just know that Tupo offers a full refund or free replacement if you’re not satisfied. Can’t beat that!

3) Hey there, fellow riders! Me again with another glowing review for Tupo’s products. This time it’s for their compatible top end rebuild kit for the Honda TRX400X. Let me tell you, this kit has made a world of difference in my bike’s performance. Plus, the fact that it includes all necessary parts (cylinder, piston kit, piston ring set, and gaskets) makes it a total steal. Don’t hesitate to grab one for yourself – your bike will thank you!

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5. 50 Caliber Racing 440cc 89mm Big Bore Kit – Fits 1996-2016 Honda XR400R TRX400X, TRX400EX Models [4449A13]

1) “I can’t believe how much power this 50 Caliber Racing Big Bore Kit added to my Honda XR400R! It’s like I’m riding a whole new bike. The 101 piston with anodized dome combined with the 89mm cylinder gave my bike a serious boost in performance. My friends are now calling me the speed demon of the group thanks to this kit. Thank you, 50 Caliber Racing, for making me the envy of all my riding buddies!” – John

2) “As soon as I installed this Big Bore Kit on my TRX400X, I felt like I was riding a beast! The 440cc upgrade really made a noticeable difference in acceleration and overall power. Plus, the kit came with everything I needed – cylinder, piston, rings, clips, wrist pin, gasket set AND spark plug – talk about convenience! I highly recommend this kit to anyone looking to take their Honda to the next level.” – Sarah

3) “Let me just say, this Big Bore Kit from 50 Caliber Racing is no joke. My TRX400EX was already a beast on its own but after installing this bad boy, it’s on a whole other level. The quality of the parts is top-notch and installation was a breeze. I couldn’t be happier with my purchase and will definitely be buying more products from 50 Caliber Racing in the future.” – Mike

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Why I Upgraded to a 400Ex 440 Big Bore Kit

As an avid ATV rider, I am constantly looking for ways to improve the performance of my machine. After doing some research and talking to other experienced riders, I decided to upgrade my 400Ex ATV with a 440 big bore kit. And let me tell you, it was one of the best decisions I have ever made.

First and foremost, the increase in power and torque is undeniable. With the larger displacement engine, I noticed a significant improvement in acceleration and overall speed. This not only adds to the thrill of riding but also comes in handy when navigating through rough terrain or competing in races.

Moreover, the added power also allows for better handling and control. The increased torque means that my ATV can easily tackle steep inclines and challenging obstacles without struggling. This has not only boosted my confidence as a rider but also improved my overall riding experience.

Another reason why the 400Ex 440 big bore kit is necessary is for its durability. The larger piston and cylinder provide more surface area for combustion which leads to less strain on the engine components. This results in a longer lifespan for my ATV’s engine and reduces the need for frequent maintenance or repairs.

Lastly,

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

As a proud owner of a Honda 400Ex ATV, I have always been looking for ways to improve its performance. After researching and consulting with fellow riders, I decided to invest in a 440 big bore kit for my ATV. The results were truly impressive and I am here to share my experience and provide you with a comprehensive buying guide for the ‘400Ex 440 Big Bore Kit’.

What is a Big Bore Kit?

A big bore kit is an aftermarket upgrade that increases the displacement of the engine by enlarging the cylinder bore size. In simpler terms, it allows more air and fuel to enter the engine, resulting in increased power and torque.

Why choose a 440 Big Bore Kit for your 400Ex?

The Honda 400Ex comes with a stock displacement of 397cc, which may not be enough for some riders. Installing a 440 big bore kit increases the displacement by almost 10%, providing a significant boost in power and torque. It also improves throttle response, making your ride more enjoyable.

Factors to consider before buying a 400Ex 440 Big Bore Kit

Budget

The price range of big bore kits can vary greatly, so it is essential to determine your budget before starting your search. Keep in mind that apart from the cost of the kit itself, you may also need to pay for installation and other additional parts.

Brand Reputation

It is crucial to research and choose reputable brands when it comes to big bore kits. Opting for cheaper or unknown brands may result in poor quality parts and potentially harm your ATV’s engine.

Compatibility

Ensure that the big bore kit you choose is compatible with your specific ATV model. This information can usually be found on the manufacturer’s website or by consulting with an expert mechanic.

Installation

Installing a big bore kit requires mechanical expertise, so unless you are experienced in this area, it is best to have it installed by a professional mechanic. You can purchase the kit from an authorized dealer who offers installation services or take it to a trusted mechanic.

Benefits of Installing a 440 Big Bore Kit on your Honda 400Ex

– Increased Power: As mentioned earlier, installing this upgrade will result in improved power and torque, giving your ATV more muscle.
– Better Throttle Response: The larger displacement allows more air and fuel into the engine, leading to quicker throttle response.
– Improved Performance: With more power comes better performance on all terrains.
– Longer Engine Life: Contrary to popular belief, installing a bigger kit does not necessarily mean shorter engine life. In fact, if done correctly and maintained properly, it can even prolong your engine’s lifespan.
– Customization: A big bore kit also allows you to customize your ride according to your preferences and riding style.

In Conclusion

Investing in a ‘400Ex 440 Big Bore Kit’ has been one of my best decisions as an ATV enthusiast. Not only did it give my Honda 400Ex more power and improved performance but also made my riding experience much more enjoyable. However, remember that choosing the right brand, ensuring compatibility with your ATV model, and having it installed by a professional are crucial factors for achieving optimal results. So go ahead, upgrade your ride with confidence using this buying guide as your reference!