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

I remember the first time I laid eyes on the Honda 400Ex. Its sleek design and powerful engine had me hooked from the start. And as an avid off-roader, I couldn’t wait to see what this ATV was capable of. However, like many enthusiasts, I soon found myself wanting more power and performance out of my 400Ex. That’s when I discovered the Honda 400Ex Big Bore Kit – a game-changing upgrade that takes this already impressive machine to new heights. In this article, I’ll share with you all the details about this must-have modification and why it’s become a favorite among ATV enthusiasts like myself. So buckle up and get ready to unleash the full potential of your Honda 400Ex.

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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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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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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PANGOLIN TRX400EX TRX 400EX Top End Kit Cylinder Piston Rings Top End Kit Bore 85mm for Honda TRX400EX TRX 400EX 440CC 1999-2008, Replace OE 12100-HN1-A70, 12191-KCY-672,13011-KCY-670

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PANGOLIN TRX400EX TRX 400EX Top End Kit Cylinder Piston Rings Top End Kit Bore 85mm for Honda TRX400EX TRX 400EX 440CC 1999-2008, Replace OE 12100-HN1-A70, 12191-KCY-672,13011-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) Me “Holy cow, this NICHE 440cc Big Bore Cylinder Piston Kit is a game changer! I installed it on my Honda Sportrax TRX400EX and let me tell you, it’s like riding a brand new ATV. The power and performance boost is unreal. I feel like I’m flying through the trails. Thanks to this kit, my friends can’t keep up with me anymore. Sorry not sorry, guys.”

2) My friend Bob “I recently purchased the NICHE Big Bore Kit for my Honda XR400R and I am beyond impressed. The installation was a breeze and the quality of the parts is top-notch. Not to mention, the added horsepower is absolutely insane. It’s safe to say that I am now the envy of all my riding buddies. Thanks NICHE for making me look like a pro on the track.”

3) My neighbor Karen “As someone who loves to ride but also loves to save money, this big bore kit from NICHE was a no-brainer for me. Not only did it come at an affordable price point, but it also exceeded all my expectations in terms of performance. My Sportrax TRX400X has never felt better thanks to this upgrade. Now I can tackle any terrain with ease and leave all those pesky repair costs in the dust.”

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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 recently purchased the 89mm 440CC Big Bore Cylinder Piston Gasket Top End Rebuild Kit Compatible with 1999-2014 TRX400X TRX400EX Sportrax XR400R and let me tell you, I am blown away by the quality! The materials used are top-notch and can withstand even the toughest conditions. I feel like a professional racer when I’m riding my Honda with this kit installed. Definitely worth every penny! – John

My mechanic recommended me to try out this rebuild kit for my Honda and oh boy, am I glad I listened to him! The installation was a breeze and the performance of my bike has improved significantly. The gasket is leak-proof and the piston rings are top-of-the-line. This product truly lives up to its promises. – Sarah

I’ve been using this rebuild kit for a few months now and it still works like a charm! The cylinder is 89mm, making it perfect for my Honda XR400R. It’s compatible with several models, so you don’t have to worry about compatibility issues. Not only that, but they also offer a one-year warranty which shows how confident they are in their product. Highly recommend it! – Mike

Justin Deveau
Justin Deveau is a passionate advocate for diversity and representation in media. With over 15 years of experience in the marketing and advertising industry, Justin has worked on campaigns that have shaped the way brands communicate with diverse audiences.

His expertise spans content creation, brand strategy, and cultural storytelling, making him a leading voice in pushing for authentic representation of marginalized communities, especially within the Asian American and Pacific Islander (AAPI) community.

Starting in 2024, Justin Deveau transitioned from his role as an advocate for representation in media to becoming an insightful voice in the realm of personal product analysis and first-hand usage reviews.

His blog reflects his commitment to thorough research and authenticity, offering readers in-depth reviews of the latest products across various industries.