Unleash the Beast: Why a Honda Trail 90 Big Bore Kit is Your Ticket to More Fun
Alright, let's be honest. If you're reading this, you probably already have a soft spot for the Honda Trail 90, or its slightly beefier cousin, the CT110. These bikes aren't just motorcycles; they're legends, workhorses, and often, beloved members of the family. From their humble beginnings exploring fire roads and hunting trails to becoming the quintessential "take-it-anywhere" companion, the Trail 90 has earned its stripes. But let's face it, sometimes that little 90cc thumper, as charming as it is, leaves you wanting just a tad more oomph.
You know the feeling, right? You're chugging up a steeper-than-expected hill, or maybe trying to keep pace with traffic that's moving just a little quicker than your speedometer allows, or perhaps you've loaded it up with a cooler and some fishing gear, and suddenly, that legendary little engine feels a bit strained. That's where the magic of a Honda Trail 90 big bore kit comes into play. It's not about turning your classic into a rocket ship, far from it. It's about giving it the extra grunt, the confident torque, and the improved hill-climbing prowess you always wished it had. It's about making a great bike even better, more capable, and frankly, a lot more fun.
What Exactly is a Big Bore Kit, Anyway?
Before we dive deep, let's quickly clear up what we're talking about. A "big bore kit" for your Trail 90 isn't some black magic; it's a straightforward engine modification. Essentially, it replaces your stock cylinder and piston with a new, larger-diameter cylinder and a matching piston. This increases the engine's displacement – meaning the amount of air/fuel mixture it can suck in and compress – which directly translates to more power and torque.
Think of it like this: your stock 90cc engine is a decent little guy, strong for its size. A big bore kit gives it a bigger chest to breathe with, allowing it to produce more power without changing the fundamental stroke of the engine (how far the piston travels up and down). You're going from 90cc to something like 105cc, 110cc, or even 125cc, depending on the kit. It's a noticeable bump, but still keeps the engine characteristics that make the Trail 90 so lovable. We're not talking about anything crazy here, just a significant upgrade to its existing capabilities.
Why Bother Going Big Bore on Your Beloved CT90?
So, why would you invest your time and money into a Honda Trail 90 big bore kit? The reasons are pretty compelling, especially if you actively use your bike for its intended purpose.
More Power, More Confidence
This is the big one, obviously. That extra displacement means more horsepower and, crucially for a bike like the Trail 90, more torque. What does that mean in real-world riding?
- Hill Climbing: Say goodbye to getting bogged down on inclines. That extra grunt will help you power up trails and hills with much less effort and far fewer downshifts. You'll feel a significant difference when you're loaded down with gear.
- Carrying Capacity: Whether it's a passenger, camping gear, or just a big load of groceries, your bike will handle the extra weight much more gracefully.
- Keeping Up: While it won't make your Trail 90 a highway cruiser, it will certainly help you maintain speed more easily on rural roads and keep up with slower traffic without feeling like you're wringing its neck.
- Just More Fun: Honestly, a little more power just makes the riding experience more enjoyable and less stressful. You won't be constantly wondering if you're going to make it up the next incline.
Modern Reliability and Durability
Many modern big bore kits aren't just about size; they often come with improved materials and manufacturing tolerances compared to original components from decades ago. You're getting a fresh cylinder bore, new piston rings, and often a lighter, stronger piston. This can actually contribute to better long-term reliability for your engine's top end, especially if your old cylinder was showing signs of wear or scratches. It's like giving your trusty old engine a new lease on life.
The Satisfaction of Customization
There's an undeniable joy in making something your own, right? Installing a big bore kit is a fantastic way to personalize your Trail 90 and tailor it to your specific needs. It's a project that yields tangible results, and there's a real sense of accomplishment when you fire up that newly upgraded engine for the first time. Plus, it's a great excuse to get your hands dirty and learn more about how your bike ticks.
Choosing the Right Honda Trail 90 Big Bore Kit
Alright, you're convinced. Now, how do you pick the right kit? There are a few key things to consider:
Displacement Options
The most common big bore kits for the Honda Trail 90 typically bump you up to around 105cc, 110cc, or sometimes even 125cc. * 105-110cc Kits: These are often the easiest to install, requiring minimal (if any) case modification. They offer a very noticeable power boost without pushing the engine too hard. This is probably the sweet spot for most riders looking for a significant but straightforward upgrade. * 125cc+ Kits: Some kits will take you further, but often require boring out the engine cases to accommodate the larger cylinder skirt. This is a more involved process and usually requires professional machining, adding to the cost and complexity. It's certainly possible, but usually for those who want maximum power and are comfortable with a more intensive build.
Kit Components
A good quality Honda Trail 90 big bore kit should include: * A new cylinder (obviously!). * A matching piston. * Piston rings, wrist pin, and retaining clips. * All the necessary gaskets for the top end (head gasket, cylinder base gasket).
Make sure you're getting a complete kit from a reputable manufacturer. Brands like TB Parts are well-known in the mini-bike and small displacement Honda world for producing quality components.
Don't Forget the Supporting Mods!
This is super important: a big bore kit isn't just a bolt-on-and-forget deal. Your engine is now breathing more air, which means it needs more fuel. * Carburetor Jetting: You will almost certainly need to re-jet your carburetor to match the increased airflow. Running too lean will cause overheating and potential engine damage. This involves swapping out the main jet and possibly the pilot jet for larger ones. It takes a bit of trial and error, but it's crucial for optimal performance and engine longevity. * Air Filter: A higher-flowing air filter can complement the big bore kit, allowing the engine to breathe even better. * Exhaust: While not always strictly necessary, a less restrictive exhaust system can help the engine expel gases more efficiently, further maximizing the gains from your big bore kit.
The Installation Journey: What to Expect
Let's be clear: installing a big bore kit isn't brain surgery, but it's also not just changing a tire. If you're comfortable with basic engine mechanics, have a good set of tools, and follow instructions carefully, it's a very rewarding DIY project. If you're unsure, or don't have the right tools (like a torque wrench, which is essential!), it might be best to enlist the help of a mechanically inclined friend or a professional.
The process generally involves: 1. Removing the top end: This means taking off the gas tank, exhaust, carburetor, cylinder head, and then the original cylinder and piston. 2. Installing the new kit: Putting the new piston on the connecting rod, sliding on the new cylinder, and then reinstalling the cylinder head with fresh gaskets. 3. Timing: Re-setting the camshaft timing is critical for the engine to run correctly. 4. Reassembly: Putting everything back together carefully. 5. Carburetor Tuning: As mentioned, this is where the real "art" of the install comes in. You'll need to adjust jetting to get the air-fuel mixture just right. 6. Break-in: Just like a new engine, your big bore kit will need a proper break-in period. This usually involves running the engine gently for a specified number of hours or miles, avoiding high RPMs and heavy loads, to allow the piston rings to seat properly. Don't skip this step!
After the Install: The Payoff
Once your Honda Trail 90 big bore kit is installed, broken in, and the carburetor is dialed in, you'll immediately notice the difference. That little Trail 90 will feel stronger, more responsive, and more capable. Hills that used to be a challenge will be tackled with confidence. Hauling gear won't feel like such a struggle. The engine will purr with a deeper, more authoritative tone.
It's not going to win any drag races, and it's still very much a Honda Trail 90 – rugged, reliable, and charmingly slow by modern standards. But it will be a significantly better Trail 90. One that makes you grin a little wider every time you twist the throttle, knowing you've unlocked even more potential from this legendary machine.
Final Thoughts Before You Dive In
A Honda Trail 90 big bore kit is a fantastic upgrade that breathes new life into an already iconic motorcycle. It's a way to enhance its inherent utility and fun factor, making it an even more capable companion for all your adventures. Just remember to do your research, choose a quality kit, and be prepared for the tuning and installation work involved. The reward, however, is a significantly more capable and enjoyable ride, proving that sometimes, a little more displacement goes a very long way. Happy trails, and happy wrenching!