2012 Street Tire Test | Absolutely Tired

If there is one single component that can make the biggest difference to the overall performance of your sportbike, it’s those rubber hoops spooned around the wheels. With the ever-increasing power and handling of today’s sportbikes, transferring that power to the ground and directing all that energy around corners becomes an extremely difficult task for a tire, yet as you’ll see here in these pages, all of the latest sporting rubber currently available is well up to the task.

It’s been quite a while since we last conducted a sport tire (tires intended for street use, with a possible track day thrown in here or there) comparison test — exactly seven years ago, in fact (“Street Sense”, December 2005). Since that time, the sportbike tire market has segmented itself into increasingly specific genres. Besides the sport and DOT race tire sectors, now the street/track day and sport-touring categories have grown increasingly popular, and nearly every tire manufacturer has a specific model (some have more than one model for a category — check our “tire market” chart on page 39 for more info) for each of these particular applications.

Seven years is an eternity in the sport tire market however, so we decided a comparison test of this particular group was in order. These are the tires you would select for average street and aggressive sport riding, with perhaps the very occasional track day included somewhere in that life span. For those who get out to the track more often, you’d probably be better off with the hybrid street/track models that are now offered; we’ll be testing those, along with the latest DOT race tires, at a later date.

Test parameters

Time has taken its toll on the overall market, as two manufacturers from our last comparison have since stopped offering sport tires or dropped off the map altogether (Maxxis has ceased its street tire catalog, and Tomahawk is no longer in business as far as we know). We did have one new entry, however: Shinko tires have made a name for themselves in the past decade as a very inexpensive alternative to the more popular name brands. In fact, their cult status (and increasing market share in this tough economy) has gained the attention of the name brands, with two manufacturers specifically “re-releasing” an older model in order to offer that same economical alternative within their own lineups. We have a total of seven manufacturers represented in this comparison test: Avon, Bridgestone, Continental, Dunlop, Metzeler, Pirelli, and Shinko.

What about Michelin?

Most of you are surely wondering why veteran manufacturer Michelin wasn’t included in this comparison test. The reason is that the timing of our test was just a little too early to allow Michelin to get us its brand new sport tire that will be making its debut soon after you read this. The Pilot Power and Power 2CT will be replaced by this new tire, thus precluding us from using either of those models. We’ll be getting some sets of this new generation Michelin sport tire soon, and will give you the lowdown as soon as we’re able.

Back to the test…

As before, each model was weighed, and its sidewall and tread construction noted. After the tire was mounted, the circumference, sidewall height, and section height and width were all measured; this data is all listed in the chart on page 38. We made any chassis ride height adjustments to compensate for any differences in overall circumference heights only if the test riders (Editor-in-chief Kunitsugu, who rode the CBR600RR, and Associate Editor Bradley Adams riding the GSX-R1000) felt it necessary by adjusting spring preload in the front.

As shown in our data acquisition sidebar on page 40, the test loop this year was different due to the relocation of our editorial offices to El Segundo, California. The 130-mile test loop still includes a good mix of urban city, highway, and canyon curvy roads snaking through one of the many mountain ranges in Southern California, taking about 3.5 hours total to traverse on average. The variety of corners on this loop is easily a match for the previous one; everything from smooth and grippy to choppy and dirty pavement, fast corners, slow corners, elevation and camber changes that challenge every aspect of both a tire’s and rider’s performance, hard braking, trail braking, changes in tarmac — you could say that this loop has it all.

As before, while we’d like to say we included wet weather testing as part of this comparison, unfortunately rain in the late summer in Southern California is basically nonexistent. Regardless, it’s extremely difficult to conduct repeatable, reliable wet test parameters with the resources we currently have.

At the completion of each test loop, Kunitsugu and Adams each filled out a ratings sheet that included 30 parameters in four different categories of performance: general, braking, traction, and steering. General characteristics include break-in and warm-up time, feedback, predictability, compliance, stability, and confidence among others. Braking characteristics include feedback, predictability, stability, and mid-corner behavior. Overall grip was rated on smooth and bumpy pavement, at maximum lean, and in slow or fast corners; and steering was graded on categories such as effort, neutrality, precision, and linearity, among others.

Um…where’s the racetrack testing?

We’re sure some of you out there are wondering why we’re not including racetrack lap times as a measurement of these tires’ performance. For tires that are specifically intended for that environment such as the sport/track day or DOT race categories, that would normally be the case. But the main reason we don’t here is because the vast majority of these tires that are sold will only see the street for their entire life span. Using racetrack aggression levels and speed to measure a street tire’s performance and feel is unrealistic, because the tires will likely (and hopefully) never experience those upper-envelope speeds and ultra-aggressive usage on public roads; this test is meant to measure the performance of the tires at speeds that are much more relevant to those that they will see on the street, which is a completely different setting than the controlled environment of the racetrack.

Make no mistake — most of these tires would not be out of their element for the occasional racetrack foray. The overall performance of this category has risen by leaps and bounds in seven years, and quite truthfully, you would have to be riding at a pace on public roads that borders on reckless to really need a tire with better grip. Yes, DOT race takeoffs from the local racer are probably cheaper, but it should be remembered that those tire compounds are made to endure only one or two heat cycles (both of which were probably used up before they were re-sold), and overall grip won’t be the same as when they were new (nor will the tread on the sides, mostly torched from numerous hard racetrack laps). And there’s no need to go into how foolish running racing slicks on the street is…

Reading the capsules

For each tire, the SR Rating is based on the average of all the scores for that tire (30 total ratings, from a scale of 1 – 10). There are four ratings categories: general, braking, traction, and steering. The scores in the capsules are the averages of those scores in each particular category from the aformentioned sub-categories and are displayed for both the 600 and the 1000.

As always, we urge you not to just blindly go with the tire with the highest overall rating, and instead read the capsules and the riders’ subjective comments to find the right tire for the type of riding that you do and the makeup of the roads in your area.

You’ll also note that the section dealing with tire pricing has changed from our usual policy of just listing the manufacturer’s suggested retail price. Because price fluctuates so much between retailers, we decided to average the listed prices from a handful of popular online motorcycle accessory chains, and come up with a number that way. We feel this more accurately reflects what you’ll find when you go shopping for tires, whether through a traditional brick-and-mortar bike shop or through an online source.

AVON 3D ULTRA SPORT SR RATING 83.5

We found the new Avons to be a huge step up in performance from the old VP2, and were very impressed with their performance. Steering habits were definitely the lightest in the test, with very little effort needed to initiate a turn or change lines midcorner; “The Avons feel similar to wearing the latest ultra-light running shoes,” remarked Bradley. The 3D Ultra Sports were also one of the quickest at major chicane transitions, and steering precision was rated highly by both riders. Overall traction and braking also garnered high marks, with the Avon’s somewhat soft construction feel providing a decent ride on the highway while also handling rough and imperfect pavement superbly.

BRIDGESTONE S20 SR RATING 86.3

Immediately noticeable with the S20 was its incredibly quick break-in and warm-up characteristics; the new Bridgestones exhibited no slippery or squirmy tendencies in the first few miles, and provided surprising grip in the first canyon turns the testers encountered. “Didn’t expect this,” said Bradley, adding that “the Bridgestone felt the best out of the box, with absolutely zero break-in tread squirm.” The S20’s carcass feel is a bit stiffer than most, so highway ride was a bit harsher than the others, with sharper bumps getting felt a lot more. The flip side of that is tire feedback during nearly all aspects of cornering is very communicative — “You always know what’s going on at the tire contact patches both front and rear,” raved Kento.

Continental CONTISPORTATTACK 2 SR RATING 79.0

The Contis were one of the few tires in this comparison that had a consistent feel throughout the duration of the corner, instead of varying levels of tread squirm at different lean angles (often a sign of compound transition) like most of the others. Break-in and warm-up were extremely quick, second only to the Bridgestones (and only just, in Kento’s opinion). Kento liked the SportAttack 2’s steering habits on the CBR600RR, although Bradley wasn’t quite as enamored with them on the 1000. Both felt the Contis were very neutral; not the quickest or most precise, but certainly not the slowest or sloppiest either. Overall grip and bump absorption garnered good ratings, but both riders felt that feedback was a bit numb unless you were on the edge of the tire; “The Contis had good grip and handling,” remarked Kento, “but you had to kind of blindly trust the tire, as you weren’t really sure what was happening at the contact patch.” Bradley complained of tire deformation when it was heavily loaded in dips or large bumps that upset the chassis, zapping confidence.

DUNLOP Q2 SR RATING 92.3

The Dunlop Q2s were, in a word, outstanding. Their performance in many aspects was so good that the few gripes Kento and Bradley could come up with seemed petty in the face of the exceptional grip and handling the Q2s provide. Steering wasn’t as light as the Avons or as easy midcorner as the Bridgestones, but the Dunlops were incredibly linear and consistent through all portions of a corner or transition, and never required additional input to hold a line. Feedback and ride quality were excellent, with just enough stiffness to communicate what’s happening at the contact patch without overwhelming you with vibration or harshness over bumps. The Dunlops tracked straight and maintained traction over numerous pavement irregularities that upset most of the other tires. Simply put, the Q2s inspire so much confidence that they were easy to spot in the datalogging speed graphs. Break-in and warm-up did take longer than most however, and wear rates were on the moderate side — but those are easy tradeoffs in our opinion.

METZELER SPORTEC M5 INTERACT SR RATING 62.0

The Metzelers have a soft feel that provides one of the better rides over highway bumps, and when ridden at an average pace in the canyons, the Sportec M5 Interact behaves fairly well. Begin to ramp up the pace however, and the Metzelers start to disappoint. Bump absorption at moderate to aggressive lean angles becomes poor, with bigger hits often upsetting tire grip, requiring additional attention in the corners. Kento and Bradley also complained of a lot of squirm from the rear at max lean that sapped confidence, and steering habits were heavy and high-effort, especially when trying to tighten your line midcorner; “Steering effort is wrist-achingly high,” lamented Bradley after the test loop. Traction feedback at moderate lean angles was pretty numb, only adding to the confidence erosion. Break-in and warm-up were deemed slightly better than average.

Truthfully, the Sportec M5 Interact just has that heavy, durable feel of a sport-touring tire compared to the others in this group. And the wear rates almost seem to confirm that assessment, with the Metzelers looking basically like they’d been nicely scrubbed in.

PIRELLI DIABLO ROSSO II SR RATING 74.5

Like the Metzelers, the Diablo Rosso II tires had a nice, compliant ride on the highway heading toward the canyons. Steering habits also felt similar, with Bradley feeling the effort was just as high as the Sportecs, although Kento wasn’t as harsh in his assessment on the 600, despite agreeing that the Diablo Rosso IIs didn’t like trail-braking; any front brake usage instantly made steering sluggish and heavy. Both riders agreed that the overall traction was a far cry from the Metzeler, with much better edge grip and a more consistent feel at max lean angles. Bumps and pavement irregularities tended to upset the Pirelli however, and feedback was deemed average at best, with not much communication at any lean angle.

Wear rates were light to moderate, with the different compound sections on the rear tire clearly visible after the test loop. Break-in and warm-up were better than average, with the Pirellis coming in fairly quick up the first canyon road.

SHINKO 010 APEX SR RATING 59.6

The 010 Apex is the company’s model “designed for serious sportbike riding.” The rear 010 Apex utilizes a zero-degree JLSB (Joint-Less Steel Belted) construction, while the front tire features aramid belts; both tires are made with an “intermediate compound” and have a tread pattern with less void ratio than the usual street tire.

Break-in and warm-up with the Shinkos was the worst in this group, with both Bradley and Kento experiencing a lot of initial squirm and requiring a good five miles up the first canyon road before they had any confidence in the tire. The tire carcass rides smoothly on the highway, but any big bumps can become spine-rattling, and anything more than moderate lean angles quickly cause bump absorption and compliance to go out the window. Overall traction wasn’t bad, but rocks and pavement irregularities upset the 010 Apex more than the other tires, requiring more attention midcorner than usual. Steering was high-effort and lethargic compared to the others, and trail-braking caused some stand-up tendencies that needed some muscle to correct. Wear rates were light to moderate, with a lot of feathering at the siping edges.

Deciphering the Code

There are many letters and numbers on the tire sidewall —  Here’s what the important ones mean

The most important label is the sizing designation, which in this case reads “120/70ZR17”. The “120” indicates section width (120mm), the 70 is the aspect ratio (the tire’s profile, 70 meaning 70 percent of the section width), speed rating (Z, meaning the tire is rated for speeds higher than 149 mph), construction (R meaning radial), and the wheel diameter (17 inches). Following the size label is an additional marking (“58W”) defining the load index/speed rating for the tire. This designates the maximum speed the tire is rated for at the manufacturer’s maximum designated tire pressure with a specified load; thus, the 58 stands for a load of 520 pounds, while the W represents 158 mph. The difference between the load index/speed rating and the speed rating in the sizing designation is that the latter is rated at a reduced load.

Note that even though tires may have the same sizing designation, that doesn’t mean their actual sizes are all exactly the same. If you look at the spec chart on page 38, you’ll see that actual tire measurements can vary widely between manufacturers. This is important, because if you’re already very close on clearance between the front tire and the front fender, or the swingarm or chain with the rear tire, you might want to do some research to see if you’ll have any issues with another tire. Also important is that changing tires can often change your bike’s chassis attitude due to the difference in overall circumference (as well as tire profile), which will affect handling. Changes in ride height through minor spring preload or fork tube height/shock or linkage length often may be necessary when switching to different tires.

While tread patterns sometimes vary, often the only way you can distinguish the difference between the OEM variant and the standard off-the-shelf tire is the additional letter identification after the model designation on the tire sidewall. The OEM variant tires can sometimes be purchased from aftermarket retailers, but the best way is usually to order through your local dealer using the motorcycle OEM’s part number.

G2X Data

To gather as much information about each tire and our test loop as possible, we strapped our Racepak G2X data acquisition system to the CBR to monitor progress, recording speed, lateral and longitudinal acceleration, altitude and other GPS-based data. Kent and Bradley stayed mostly together over the course of each loop, so the data is representative of both bikes (and tires).

Because the Source Interlink offices have moved to El Segundo from the posh mid-Wilshire district in Los Angeles since our last tire test, the loop used is significantly different from previous tests. Here we chose a 130-mile loop that includes freeway, city, canyon and mountain roads, taking approximately 3.5 hours in total to complete. The map and data graph show the fun part of the loop, which includes many of the roads in the Santa Monica Mountains near Malibu; these mountains jut up from the Pacific Ocean to a height of 2500 feet in places, with myriad routes from the Pacific Coast Highway at the bottom to various peaks. The data graph displays speed (in red) and altitude (in blue).

The first and last 25 miles of the test loop are city and freeway roads to get to — and from — the base of the first climb. While not a very glamorous part of the test, here Bradley and Kent have a good chance to note compliance and stability at speed for each tire, in addition to low-speed handling manners. The first run up the mountain is a 2000-foot climb in four miles (1) on the brand new tires — a good test of warm-up and break-in characteristics, and especially interesting as this road can often collect dirt from the surrounding steep hillsides.

The road back to sea level (2) clings along the side of the mountains; because it’s significantly downhill in places, braking and steering characteristics come to the fore. Our dynamic duo then heads back to the ocean (3) and along the Pacific Coast Highway (4) to the next uphill climb. This road (5) winds to its 2000-foot peak with dozens of low- and medium-speed turns along the way. This is the longest single road in the loop, and shows some interesting data. For the 15-minute ride from bottom to top, the spread between the fastest and slowest tire is just 40 seconds, or about five percent.

The next stretch along the peak of the mountain range (6) is a series of high speed sweepers that stress stability and confidence in the tires. Then it’s back down to the ocean along a seven-mile stretch of road that covers almost every type of corner in terms of speed, camber and elevation. Every aspect of tire performance is important on this stretch, and again it’s a tight grouping of times between the tires.

The remainder of the loop sees Kent and Bradley heading back up the mountains and along the peak returning along some of the same roads, and finally down to the ocean the same way they originally went up. Of particular note here is the last section over the peak of the mountain and down to the ocean (13 and 14). Both roads are quite technical and challenging, with the last road especially so as it is a steep descent. With our riders well familiar by this point with the tires’ characteristics, it’s a last opportunity to test any traction limits as well as braking, stability and confidence before the drone back to the office.

From the times recorded for each road, it’s the Dunlop that was consistently the quickest over the course of the loop, a reflection on Kent’s and Bradley’s confidence in the tire and its performance. That said, it’s worth noting how well all the tires performed. The total time for the twisty parts of the loop is approximately 70 minutes, and less than three minutes separates the fastest and slowest times. In other words, all of the tires tested here are capable of whatever speed you deem appropriate for street riding, and there are other factors that determine how fast you can — or should — ride on the street.

Bradley Adams

Dunlop raving aside, I was also impressed by the BridgestoneS and Avons since they complimented the sporty feel of the GSX-R1000. The rest of the bunch gets the job done, but really affected overall ride quality and confidence. At the end of the day, I want to purchase a tire that’s going to enhance my ride, not hold it back, and that’s where the Dunlops excel.

Kent Kunitsugu

There’s no doubt that tires are a very expensive consumable item on bikes, and for those who ride often and hard, the rubber budget is often a very carefully considered figure that has to weigh all the options. For some, price is the overriding factor in the decision, and in this still-struggling economy, that’s totally understandable. But I will say this to those who always go for the cheapest option: you owe it to yourself to try the top-tier tires in this test at least once. You won’t be disappointed.