— Testing Teixeira Tech products —
By the staff of Dirt Wheels
Yamaha’s YFZ450R is an excellent machine right off of the showroom floor, but there is always room for customization to suit your riding needs. We pilot our machines in areas where rocks and ruts are prevalent. We already roasted our stock plastic swingarm skid plate and weren’t content lifting the quad by the front GYTR bumper to get it unstuck. Fortunately, Teixeira Tech makes a steel/aluminum/poly swingarm skid, aluminum sprocket guard and a front bumper with more usable grab handles.
We also learned about TT’s upper-control arm kit for the Yamaha. This kit comes with a bracket and mounting options to change the castor and camber on your Yamaha without having to change the lower A-arms. The parts make dialing the YFZ450R for different terrain a breeze, and saving some coin while upgrading our ride is a plus, so we picked up a set!
We started off by installing the swingarm skid plate and sprocket guard. The $139 skid is made of stainless steel, aluminum, and UHMW polyethylene. The main steel plate is expertly welded and gusseted to allow for great ground clearance. It is durable enough to handle a lot of abuse. An aluminum guard is attached to the sprocket side of the plate, while a UHMW poly guard helps protect the rotor. Both pieces can easily be replaced when they wear down.
The $65 aluminum sprocket guard, that attaches to the spocket and its mount, is a stout 3/8ths of an inch thick. We bolted it up with ease, and the wheel hub on the sprocket side does not need to be removed during installation. This added bit of protection helps keep your sprocket from bending which would result in a broken or slipped chain. That could end your ride or race quickly. All of the needed installation hardware comes with the guard, and it pairs perfectly with the swingarm skid plate.
Our 2019 Yamaha YFZ450R Special Edition comes stock with a small and sporty looking bumper. Unfortunately, it isn’t too easy lifting the front end around to get the ATV unstuck. It also doesn’t have the vast coverage that Teixeira Tech’s XC bumper does. TT’s bumper sells for $129 and was put to good use during our testing.
CONTROL IS KEY
Teixeira Tech’s upper A-arm kit is a treat. Yamaha designed the stock upper and lower A-arm mounting locations to not sit parallel with each other. The rear upper mounts sit closer to the bottom of the frame than the upper front mounts. TT created a castor bracket, new A-arm mounting bolts and flanges to change the geometry. Teixeira wants to have the A-arm’s ball joint mounts ride on a parallel plane. The benefits are more control out of corners, and more stability over the rough and in whoop sections.
The end of the new upper A-arms have adjustable ball joints to allow you to dial in camber. The ball joint mounting system offers forward and rearward mounting adjustments to change how quickly the ATV will steer. Teixeira calls it their Pro Castor/Camber System. The kit comes with heavy-duty Frap ball joints, and you can upgrade to needle bearings on the pivots of the arms. Pricing starts at $412.
Installation of the upper arms got a little tricky. We started by putting the Yamaha on a stand and removed the front wheels. Next, we popped the upper ball joints loose with a removal tool, disconnected the brake calipers and lines, removed the shocks and removed the upper A-arm mounting hardware to remove the stock arms.
Installing the Teixeira castor plate requires some customization. We ground away the inner sections of the mounting bracket to make for a proper fit on the rear mounts. We also removed the bushing on the front mounts and replaced them with TT’s flanges that assist with changing the mounting angle.
Once the new arms were mounted up to the Yamaha, we could reroute the brake lines and attach them to the arms (we used zip -ties with the stock lines to reattach them since temporarily the OEM equipment could no longer be utilized). Then the new ball joints were loosely connected to the arms, and installed onto the spindles. We sanded some powder coat away from the inside of the ball joint
Some steering adjustments can be made with the quad set back on the ground, but adjusting the castor is easiest on a stand with the front tires removed. The Teixera Tech Pro system allows you to position the upper ball joints in five different positions to set the castor. Moving the ball joint towards the rear of the mount makes the turning lazier and allows you to have more stability during high speed riding. The opposite mounting direction helps the ATV turn quicker, but it wanders more at high speeds.
The ball-joint shafts that connect to the upper A-arms are long enough to adjust the camber of the Yamaha. Most often, the wheels of an ATV are straight up and down, or slightly angled inward on top which is called negative camber. The more inward the top of the tires are, the more load will be spread to the entire tread and will increase traction in corners. But adjusting this too far inward hinders control in other situations by allowing the tires to pull more. It causes more tread wear on certain parts of the tire.
Make sure to check the toe of the machine as well. An 1/8-inch of toe-in is our general rule of thumb. Before you ride the machine, properly check and tighten all hardware after installation and adjustments.
While testing Teixeira Tech’s swingarm skid plate and sprocket protector, staffer Collin Duffy’s goal was to hit as many rocks and ruts as he could find on an abusive trail ride. He piloted the machine into rocks more suitable for a 4×4 quad to tackle. After hard days riding, the skid and sprocket guard showed some wear, and a little bend at the end of the stainless steel skid plate. However, they performed their duties very well and we had no issues with the sprocket, chain or rotor. While our rotor had shone no damage during testing, we could assume that the poly protector could possibly be a bit too pliable under extreme situations and allow the rotor to be damaged.
We did manage to get the Yamaha stuck on a few sections of a creek trail when Duffy high-centered the axle bearing carrier on some suitcase-sized rocks. The XC bumper was very helpful while lifting the front end of the quad around and getting it pointed back in the right direction.
The most obvious changes came from the upper-control arm kit. We instantly noticed the improved stability at higher speeds with the new angle of the arm. With the ball joints mounted in the middle of the castor adjustment, we felt steering was hindered a little compared to stock. Once we moved the ball joints all the way forward, steering was improved over stock. Pulling the ball joints all the way back in the mounts increased high-speed stability and tracking over rough terrain quite a lot. The Yamaha would wander while skipping over whoops before, and now it stays straighter and is easier to wrangle.
Teixeira Tech continues to impress us with their products. We are seeing their parts on more ATVs and UTVs these days, and it makes a lot of sense. Go to www.teixeiratech.com or call (209) 833-9160 to see their full product line, or order these parts for your Yamaha YFZ450R!