Kings KT-921 Sand Rib Tire

Kings Sand Rib Tire

Ok, so there’s the picture, what we have here is essentially a three rib sand tire. Here’s the manufacturer’s claims…..

  • A unique three-rib directional tread design increases cornering ability
  • A must for all “serious” sand riders
  • Light weight and fl exible carcass offers added flotation in deep, soft sand


So looking at the tire and getting a good deal at the Sand Sport Super Show ($30) this year we all decided to grab them and mount them up for the first trip of the year. The test bikes included a 2005 CRF450X and a 2003 CRF450R. We’ve got a season of sand riding experience under us and a couple years of sand rail experience each, so we’re fairly well versed in sand riding requirements and what goes on. With the sand being one of our favorite riding spots (much better than the whooped out desert) we decided to head out to Dumont Dunes as our sandbox which is about 45 minutes outside of Baker. Just look for the world’s tallest thermometer and turn left towards death valley. It’s a medium sized playground with some of the tallest and steepest dunes with a very healthy number of razorbacks (Danger! Danger! Danger!). It’s our preferred riding spot being a little over two hours away.
In prepping the CRF450X for the sand there are a couple of things you must pay some attention to in preparation for the trip.

-Paddle tire.
Sand riding is extremely hard to ride all day without a paddle tire and it’s reccomended that you purchase one for your trip. Most paddles are available in 8 or 10 cups (paddles). Personally I prefer the 8 paddle tire. And this is what we’ve mounted up. In order to do this there are several steps you need to take.
-The paddle tire is quite a bit bigger than the stock tire. You’ll need to move your wheel back in the swing arm. This can be accomplished in one of two ways.
-Run a longer chain, this will allow you to move the paddle tire back farther.
-Swap your sprocket for a 49 tooth sprocket, this allows you to move the wheel further back in the swing arm, allowing for the extra clearance.
I’ve run it both ways on my CRF450X and the only difference is the gearing and the speed you’ll run in the dunes. Most duning is in 3rd and 4th gear with the occasionally 5th gear blast through some whoops.
-You should seal your air filter assembly to the base with some sealing grease. K&N makes some good paste. Sand is very small and can and will work it’s way in everywhere. Sealing the air filter base just allows you some extra insurance. While I’m not a believer that some sand injested in your motor will instantly ruin it, the long term effects on the cylinder walls are best to avoid if possible.
-Your mud flap needs to be removed from your swingarm. If you forget this step don’t worry about it. At some point in your trip your bike will decide to remove it on it’s own. Then you’ll need to purchase one at your local dealership. Take my advice remove it. It’s also best to run a shock cover of some sort as you’ll be sandblasting the back of it all day long.
-Also remember to check the direction of your paddle once you or your local shop mounts it. There’s been more than one occasion that when picking up the tire I had to repeat the followign line “Looks great man, I appreciate it, but hey any chance we could flip it over the other way?”. It seems that swapping paddles is a pain in the … and is usually pawned off on the new shop hire (AKA Trainee..).

Upon arriving we noticed that the sand sport is becoming quite popular. The population of toy haulers was close to double of anything we’ve seen in previous trips and there we’re an abundance of motorcycles of the 2 wheel variety cruising the dunes, we even spotted 2 other CRF450X out in the dunes. This is a litte unusual in that usually you can go a couple hours and only see quads and sand rails, looks like times are changing. The one thing noticeable was that our bikes were the only ones sporting the front rib tire.

Onto the tire, upon unloading the bike and riding it over to it’s parking spot it was immediately noticeable that this tire did not act like your normal tire in the sand. It was definately more responsive and brought quite a bit of control back to the front tire. A little testing in the flats brought about the same conclusion, this tire definately allowed the front end to track according to rider input. So now a little bit of a sand lesson break….

There are two different sand tires that buggies and quads use in the sand.
-The first is called a smoothie tire, and ressembles an inner tube.
Smoothie Sand Tire.
The second tire is called a sand rib and has ribs running around the tire. These tires are usually referenced by the number of ribs (3 rib, 5 rib, etc…).

3 Rib sand tire

In the sand there is a balance between floatation (the ability to keep the front end up on top of the sand), and steering. If you float the front end too much then you can’t steer resulting in a condition known as push or understeer. Conversely if you have too much steering and not enough flotation you’ll result in a condition called over steer, where the vehicle responds too much to the steering. A lot of this depends upon the weight distribution to each tire and the configuration of the chassis and the rear tires. To simplify it, You get less steering control with a front tire using a smoothie and more steering control using a ribbed tire. These tires look agressive and you’ll look like you mean business when you head out to the sand.

So onto the ride test… We fueled up the bikes, dialed the Scotts stabilizer to the stock setting of 8 clicks from full hard and head out to the dunes. The control of the front tire was still very noticeable, in previous rides using a Dunlop 756 the steering input was diminished and in a lot of cases we used throttle steering (control the bike with the amount of throttle) to navigate the bikes to their proper heading. Not the case with this tire, where you pointed it was were it went. This sounds like the ideal situation right?

Wrong. Sand is a constantly changing surface. It’s not a flat smooth medium. It’s a very hilly rutted constantly changing non flat surface and herein lies the problem. This tire works so well that everytime you hit any surface imperfection it grabs and steers you the way that it wants you to go. Some of you that have ridden with and without stabilizers can realte best. Imagine riding a rocky trail with a stabilizer, your allowed to pick your line and bounce off the imperfections, now once you turn that stabilizer off the rocks have it’s way with your front end. That’s the best example of this tire. It’s going to take off which ever way it ends up pointed. I kept dialing up the Scott’s until I couldn’t turn the bars on my own, but to no avail. This thing tracks where it’s pointed and if the sand points it some where else your going then that’s where you are headed. That’s when it hit me, this tire has zero flotation, it doesn’t skim the surface it cuts down and rides in the sand. This was verified by several test with body position, too far forward on the bike and your in for a ride. A couple of others on the ride with their quads also commented on how it looked like our bikes we’re plowing through the sand. Unfortunately this seriously effects the riding experience and causes the rider a lot of undo work due to the amount of effort required to keep the bike on your intened path, not the front tire. So let’s check those manufacturer claims one more time…..

  • A unique three-rib directional tread design increases cornering ability – Yes they do. You’ll turn on a dime whenever the wheel goes one way or the other. How many times have you almost “Packed it” or cased a jump, into the face of the takeoff. Don’t get squirrly with this tire or your going for a a ride.
  • A must for all “serious” sand riders – If your a serious sand rider it’s worth a shot just to further understand the dynamics of the sand and riding in it, and you’ll definately like the look of it before you get out there. You hard core sand guys need to try it at least once.
  • Light weight and fl exible carcass offers added flotation in deep, soft sand – Sorry, no flotation benefits at all. This tire has zero flotation, this claim must be one of those labratory tests. In the real world you take flotation away when compared to a stock tire. The tire is light, but fleixble is not a word I’d use in describing the carcass. How about stiff hard rubber, yup that’ll work.

So the conclusion after the trip? We decided these tires are meant for Quads and sandrails, not for motorcycles. While I’m sure there are some experts out there that would love these, we all think your better off running a Dunlop 756 or regular knobby tire. You’ll have more of a balance between flotation and turning ability. The trick to not going over the bars in sand riding is to keep that front end light, this tire does not allow that to happen. Ultimately if I had to ride with this tire again in the dunes, we’ll I’d rather go to the desert and ride dusty whooped out trails all day long, that’s how much this tire didn’t work for me.

Purchase Place – Cycle Parts West at the Sand Sport Super Show 2006
Link – http://www.sandsportssupershow.com/
you can find the tire online here KING FRONT SAND TIRE 80/100-21

Retail Price $39.99
Rating – 5 out of 10 only because it meets 2 out of 3 claims, for a true ride report I’d give it a -10. It made the bike a PITA to ride.

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