The Honda Rancher 420 is a great ATV for off-road riding, but with the stock tires, it can be tough to navigate terrain that requires more ground clearance and traction.
If you’re looking to increase your Rancher’s traction offroad and significantly improve the way the ATV looks, then this article is for you.
Bigger tires will not only make your Honda Rancher 420 look much better, but they will also increase ground clearance by ½ inch for every extra inch of tire that you add.
But what is the biggest tire on stock Honda Rancher 420 that you can fit without rubbing?
Biggest Tire on Stock Honda Rancher 420
The biggest tire on stock Honda Rancher 420 that you can fit without rubbing is a 27″.
Now, there are a bunch of cases where some people managed to squeeze 28″ tires on a Rancher 420, but this might not be possible if the shocks on your Honda Rancher 420 are worn and sag down a little bit.
When you’re really pushing it with tire size, even a fraction of an inch can be the difference between a perfect fit and rubbing. One of the things that a lot of riders overlook is that not all tires are true to size, meaning that while some tires are listed as 27″, they are actually 27.5″ in reality.
If you want to be on the safe side, we recommend sticking with 27″ tires.
Now, as for tire width, we always recommend going with the stock width, as it gives a great balance between maneuverability, easy steering, and floatation on mud. Most Honda Rancher 420 owners go with 9” front and 11” rear.
Rear Wheel Size Issues on the honda Rancher 420
The biggest problem that you will face while trying to get the biggest tires on your stock Honda Rancher 420 is the weird OEM rear wheel size.
The problem is that the rear wheels are 11″, which is a weird and uncommon size for ATV wheels, therefore you will have a tough time finding tires that fit 11″ wheels. This is a really weird choice by Honda and as a consequence, a lot of the most popular ATV tires are simply not available for 11″ wheels.
Luckily, there is a way to fix that!
You can easily get a set of used or new Foreman 500 wheels since they’re 12″ in the rear and front. Honda Foreman 500 wheels do fit the Rancher 420 without any issues and do not require any modifications.
If you’ve got the cash, it’s also the perfect excuse to buy new aftermarket wheels for your Rancher 420.
But if you don’t want to buy new 12″ wheels for your Rancher 420, then you can sometimes find the Maxxis Zillas for 11″ wheels.
The Zillas are one of our all-time favorite ATV tires and we highly recommend them.
Related: The Best Tires for Honda Rancher 420
Things You Need To Know Before Putting on Bigger Tires on Honda Rancher 420
While the Rancher 420 is certainly no slouch when it comes to engine power, you have to keep in mind that bigger and more aggressive tires will rob engine power.
The Rancher 420 is not designed to run really big, heavy, and aggressive tires, therefore it’s not geared to spin them very well. With big tires, the ATV will feel more sluggish and you will put more strain on the gearbox.

Another thing to keep in mind is that the foot shift Rancher 420 will have no trouble spinning 26″ and 27″ tires, because it’s got lower gearing. On the other hand, the automatic transmission models are geared higher and will likely have trouble spinning tires over 25″.
The last thing to keep in mind is that really big tires will put a lot of strain on your Rancher’s transmission and differentials. Though it’s not that big of a deal if you’re riding normally and with tires that are sized reasonably (27″), if you like to really trash your Rancher 420 on the trails and mud, then you bigger tires in combination with aggressive riding will increase drivetrain wear. Specifically, the angle gear, pinion gear, CV axle joints, clutch, etc.
Now, there is a way to prevent or at least minimize the extra wear that happens when you run really big tires, and that is gearing reduction.
In most cases, you won’t need a gear reduction for 27″ tires on an ES or foot shift Rancher 420, but if you’ve got 28″ tires or an AT model, then gear reduction is a must.
How To Put Even Bigger Tires on Your Honda Rancher 420
There are ways to put even bigger tires on your Rancher 420, but they will require some modifications.
The first and easiest way to do it is by trimming the plastics around the tires. Usually, the first places that start rubbing on a Rancher 420 are the lower parts of the front fender flares.
You can go for the invasive and permanent option of cutting the front fender flares, or you can go for the less permanent but more time-consuming method of heating up the plastic with a heat gun and molding it away from the tires.
As for the rear, you can also trim or mold the plastic fender flares away, but you can also go for the more expensive but less invasive option of installing stretched swingarms. Stretched swingarms for the Honda Rancher 420 can be found online, but they can also be custom-made. The best part about them is that you won’t have to permanently change the way the plastic fender flares look.
If you really want to go all out, then you can install a 2″ lift kit on your Rancher 420. This will give you even more room to fit bigger tires, but it will also make the ATV taller.
We do not recommend a lift kit higher than 2″ because it will be too much for the CV axle joints, as a 2″ lift kit is enough to increase wear in them.
One last thing to keep in mind is that if you decide to go with really big tires, then you will most definitely need a gear reduction kit. It’s not the cheapest thing in the world, but the Rancher 420 is simply not powerful enough and not designed to spin huge tires.
Also Read: The Biggest Tire on Honda Pioneer 700?
Conclusion
The biggest tires that you can fit on a stock Honda Rancher 420 are 27″ tires.
If you want to go with bigger than that, then you will need to make some modifications to the ATV, such as trimming or molding the plastic fender flares, installing a stretched swingarm, or installing a 2″ lift kit.
Keep in mind that bigger and more aggressive tires will rob engine power, so don’t be surprised if your Rancher feels slower with them.
Also, bigger tires will put more strain on the transmission and drivetrain components, so if you like to ride hard, then we highly recommend installing a gear reduction kit.

Nick Kowalski is a diesel mechanic by trade, but his passion lies in motorcycles.
He’s been riding them since he was just a wee lad, and he loves restoring old Japanese street bikes and ATVs in his spare time.
Nick is an adrenaline junkie at heart, and he loves nothing more than hitting the open road on his motorcycle.