The one constant with all bikes is that 2 tires are in contact with the ground. Each rider’s style dictates how often both are actually contacting the ground, but in general, two tires are recommended.

A few months ago we got a selection of knobbies from the guys Redwood, CA to play around on. One thing you immediately notice when looking over the information from Ritchey is the V.F.A. (vector force analysis) data. Ritchey has gone to great pains to develop tread designs based on how knobbies react to ground forces. Think about it, tires are involved in acceleration, cornering, braking, climbing and descending in some combination. Placement and design of knobbies is determined by the force a rider will encounter while at various angles to the ground. By applying the V.F.A. concept, Ritchey has developed a solid product line-up with a tire that’s likely to be well suited for your typical riding conditions. Now, which one is right for you?

Z.E.D. Race Pro 1.9

The Z.E.D. Race is Ritchey’s first pure race tire since the Racing K was the rage in ’88. Looking at the tread pattern, we didn't expect a lot. Our experience with last year’s Z.E.D. was less than ideal so we were pleasantly surprised when the Race Pro’s got into the dirt.

The knobs are small and lightweight but grip surprisingly well. Enhanced "grippage" is due to the stiffness of the knobs which them to bite into hard-pack and stick when the trail is slick. Race Pro’s perform best when accelerating and in controlled cornering. Though braking performance was less impressive, the "all-around" characteristics of the tire made them acceptable for all conditions. Low rolling resistance adds to the "quick" feel of the tires.

Thinking about it, when racing quick acceleration, controlled cornering, and minimal braking is key. If you’ve got a tire better than average in most of these situations, racing would be an excellent application. That’s just where the Z.E.D. Race Pro 1.9’s are at home.

Z.E.D. Race Pro WCS

Suggested Retail price: $39.95

Sizes: 26x1.7 (420g), x1.9 (490g), x2.1 (530g)

Z.E.D. Race Pro

Suggested Retail price: $31.95

Sizes: 26x1.7 (465g), x1.9 (515g), x2.1 (545g)

SpeedMax Alpha & Omega 1.9

The beginning and the end or in this case a front and rear specific tire. The design incorporates a low profile center pattern with squared ramped knobs on the Alpha (front specific, left in picture). This enhances braking especially when entering technical sections at speed. The Omega (rear specific, right in picture) includes a triangular ramp pattern for increased traction. The effect is hundreds of little scoops digging the dirt when climbing.

While not a semi-slick, the SpeedMax Alpha and Omega are fast tires best suited for racing on dry trails. This isn’t to say they don’t perform when conditions are less than ideal. On the contrary, the aggressive outer knob pattern allows for high speed cornering on wet or dry courses. There is a tendency to hold dirt with a high clay content.

Overall the SpeedMax is a favorite among experienced DirtWorld racers. They’re a bit less forgiving but are designed for performance. Based on the wear we experienced, the SpeedMax tires appear to be a one-season tire. With the intended purpose of racing, this isn’t unusual. For this reason and the performance orientation, we don’t recommend the tire for casual riders. But men and women who "get on the line" several weekends a month would be well taken care of from beginning to end with the SpeedMax Alpha and Omega offering.

SpeedMax Alpha & Omega WCS

Suggested Retail price: $35.95 (each)

Sizes (Alpha & Omega each): 26x1.9 (490g), x2.1 (530g)

SpeedMax Alpha & Omega Pro

Suggested Retail price: $19.95 (each)

Sizes (Alpha & Omega each): 26x1.9 (510g), x2.1 (550g)

Z-Max Millennium Pro

There were 2 vastly different feelings with the Z-Max Millennium Pros. The Z-Max tread is an example of Ritchey’s V.F.A. concept taken to the max. There’s knobs everywhere! The pattern isn’t dense but more constant. For cornering and braking the Z-Max was tough to beat. There’s a trade off between traction and rolling resistance. The Z-Max favors the traction side of the spectrum but rolling resistance isn’t overly compromised.

In most all conditions the Z-Max tread had rock-solid reliable performance. The 1.9 diameter offered more acceleration and performance orientation. Sticky mud packed at times but descending was sharp and true. Choose the 1.9 size for maximum versatility and occasional racing.

On the other end of the spectrum were the enormous 2.35’s. Ritchey touts these as "light downhill" tires or slalom. Light downhill? Um… we’re not so sure. The Z-Max 2.35’s don’t have a burly enough sidewall for the rigors of downhilling. And really, is there such a thing as "light downhilling"? It’s not to say the 2.35’s don’t have a place. They most definitely do and they’re all about fun! Their large footprints provide excellent traction even at higher inflation pressures and sure-footed descending. Be fore warned, these are WIDE tires and frame clearance can be an issue. Make sure your rims are wide enough to adequately hold the tires in place with sufficient clearance. Bottom line, for a day in the dirt cruising around, the Z-Max Millennium 2.35’s are the ticket for fun and comfort.

Looking for the best of both worlds? Check out the Z-Max Millennium 2.1 for a happy medium.

Z-Max Millennium Pro

Suggested Retail price: $27.95

Sizes: 26 x1.9 (525g), x2.1 (610g), x2.35 (720g), 24x2.0 (605g)

Z-Max Millennium WCS

Suggested Retail price $39.95

Sizes: 26x1.7 (442g, WCS only), x1.9 (495g), x2.1 (580g), 20x2.0 (605g)

All in all, the more experienced racers preferred the Speed Max in a 1.9 size. Those seeking a bit more sure footed handling while willing to sacrifice the rolling resistance opted for the Z-Max Millenium. Looking for a single tire to be your work horse? We'd steer you towards the Z.E.D. Race.