Riken Raptor ZR A/S Detailed Review

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Riken Raptor ZR A/S is a decent entry level pick, when it comes to ultra high performance all season tires. It’s a great option for those who need winter performance under a budget.

Porsche Cayman
Riken Raptor on Porsche Cayman.

Brief Overview

Overall, the Riken Raptor ZR A/S stands out for its strong performance in areas such as:

  • Exceptional dry braking, owing to its well-designed tread pattern and rounded contact patch.
  • Comfortable ride quality, enhanced by its flexible, winter-focused rubber compound and pliable internal construction.
  • Decent performance in light snow conditions, supported by its robust longitudinal grip and effective V-shaped lugs.

But, the tire does fall short in some aspects, mainly in:

  • Hydroplaning resistance and wet traction, which is the tire’s weakest performance area.
  • Lateral grip and handling, mainly due to its voided up shoulder lugs.
  • Tread longevity and fuel efficiency, with its softer rubber composition and heavier weight contributing to faster wear and higher rolling resistance.

Size Variations

The tire comes in 16 to 20 inches rims, with following specs.

  • Speed ratings: W only.
  • Load ratings: SL and XL.
  • Tread depth: 10/32″ on all sizes.
  • Weight: 20 to 32 lbs.
  • UTQG: 300 A A.
  • Treadwear warranty: NA.

Internally, the tire comes with 2 ply polyester, 2 steel belts, and 2 nylon cap plies.

Tread Structure

To comprehend the tire’s performance characteristics, we’ll begin with a detailed examination of tire’s tread design.

Riken Raptor ZR A/S
Riken Raptor

So, the Riken Raptor ZR A/S showcase a directional tread design crafted for high performance.

Side Note: I posted a guide on how to know if your tires are directional, and their pros and cons here – https://tiredriver.com/how-to-tell-if-tires-are-directional/

It’s pattern can be divided in to 5 sections, courtesy of 4 circumferential grooves it makes.

Here, the central-most rib is designed for unbroken contact with the pavement, ensuring reliable grip.

I mean as you can see, this rib doesn’t have any biters on it.

Whereas the surrounding ribs come with sharp edges, off-sets, and notches facing the shoulder blocks. Moreover, these lugs are the most voided up, on the tread.

Moving towards shoulders, the lugs here again adopt a streamlined approach, equipped with modest lateral voids and beveled edges.

And these lugs, just like the others, don’t come with any sipes.

A little advice: If you’re pinpointing your all-season tire choices, do take a moment to check out this page I’ve tailored for you.

Dry Performance

To gauge a tire’s dry road performance, we assess its grip on dry surfaces, its behavior during abrupt directional changes, and its steering accuracy. Let’s take a closer look.

Directional Grip

The Riken Raptor ZR A/S demonstrates exceptional traction on dry roads, particularly in terms of longitudinal (straight-line) movement, which gets measured by its superb braking efficacy.

This high level of performance is attributed to three key design features:

  • Directional Tread Pattern: The tire features a directional tread pattern with central lugs, that align optimally with the road surface, ensuring strong rubber-to-road contact.
  • Continuous Central Rib: The tire’s central rib comes with an unbroken design, and without any tread features, enhancing uninterrupted contact with the road, thereby improving grip.
  • Rounded Contact Patch: This evenly distributes the weight pressure across all its tread lugs, reducing overall momentum, facilitating easier and more efficient braking.

Additionally, the lightweight design of the tire, compared to others in its category, contributes further to its overall reduced momentum, aiding in more responsive braking.

To give you an idea about its performance, the dry braking performance of the Riken A/S is notably similar to that of the Fuzion UHP Sport A/S (review), which is also a pretty nice budget pick, in the Ultra-High Performance (UHP) all-season category.

Overall Handling

When it comes to handling, the overall performance of a tire is intricately linked to two key factors: lateral grip and steering response. To comprehensively understand their roles, I analyzed each aspect separately.

Starting with lateral grip, this pertains to the tire’s traction when it’s cornering, and it depends on the design of shoulder lugs on the tread.

But why shoulders? Well, this is because as the tire turns, the weight on it shifts (and concentrates) towards the tread edges.

This is centripetal force in action. Think of it this way: why do you think you get pulled towards the opposite side of the corner, as the vehicle turns sharply?

Now, in the case of the Riken Raptor ZR A/S, its shoulders, designed with minimal voids in the lugs, ensure excellent rubber-to-road contact, resulting in outstanding lateral traction (measured by lateral G forces, on average tests).

Though the main contribution to the tire’s impressive overall handling (seen by its lap times) comes from its effective steering responsiveness.

I mean the tire provides you with a very strong and sportier feel, along with strong front-end control.

This especially goes when the tire is in mid-cornering, where it responds well to steering inputs, balancing the effort needed to steer without feeling too heavy or light.

For Your Info: The overall handling performance of the tire is very similar to Kumho Ecsta PA51. Review it here: https://tiredriver.com/kumho-ecsta-pa51-review/

Wet Performance

A comprehensive review of a tire’s wet performance includes its ability to grip wet surfaces, respond to steering inputs, and resist hydroplaning.

Let’s take a closer look at these factors.

Aquaplaning Resistance

Hydroplaning occurs when water can’t escape from underneath the tire, causing it to lose contact with the road and float, which renders control inputs ineffective.

To combat this, tires are designed with grooves that channel water away.

This means the effectiveness of these grooves determines the tire’s overall resistance to hydroplaning.

Now, the Riken Raptor ZR, although comes equipped with a directional tread and V-shaped lugs, it still faces a challenge.

Its continuous-running central rib, combined with packed shoulders, impedes water’s lateral displacement, leading to lower float speeds, when the tire turns. However, it does offer decent performance in straight lines, as evidenced by straight aquaplaning tests.

In simpler terms, the tire expels more water longitudinally than laterally.

For reference, float speed is the speed at which a tire begins to float/hydroplane on water, often just a few millimeters deep, losing traction with the road. I use a telemetry system to accurately record the moment the tires begin to hydroplane.

Wet Traction

Wet traction primarily involves efficiently removing water from the tire’s tread, a task accomplished through the use of sipes and grooves.

Now, as mentioned, the grooves in of Riken Raptor aren’t effective enough. So them taking less water out, leads to a greater dependence on other biting elements and sipes for water removal.

These biters are small voids/slits on the tread, which draw in water particles, clearing road surface.

Now if you consider the tire’s tread again, you’d note that it doesn’t come with any siping, and only has very limited biters, in the form of curved grooves, acting as in-groove notches, and chamfered edges.

This design limitation results with Raptor ZR coming at the very last, in overall wet handling and braking performance, among its peers in its UHP all-season category.

To give you an idea about its performance, the tire lacks to Sumitomo HTR A/S P03 (which is also just an average tire here), by over 5 seconds in wet handling lap times, and over a whopping 20 feet in wet braking tests.

Side Note: You can improve tire’s wet traction by following these points here: https://tiredriver.com/are-all-season-tires-good-in-rain/

Snow Performance

The Riken Raptor ZR A/S stands out in its ultra-high performance all-season category for two main reasons: its affordability and effective performance in snow.

The tire showcase pretty decent overall performance in light snow conditions, particularly in terms of acceleration, thanks to its robust longitudinal grip.

This performance comes mainly from its distinctive V-shaped lugs/grooves, which effectively throw/scoop the snow, and slush backwards, providing superb forward momentum, in return.

Now of course its not enough to get you the 3-Peak Mountain Snowflake label, but its still appreciable.

FYI, the 3 peak rating is given to tires, which offer at least 10% excelling acceleration on soft snowy tracks, compared to standard all season tires.

Moreover, although the tire is also missing with sipes, and a lot of biters, it’s numerous voids, acting as in-groove notches, still provide decent grip overall. They effectively trap snow particles, fostering better snow-to-snow contact.

This type of contact is pretty crucial for effective snow performance. This is because snowflakes inherently adhere better with each other, compared to rubber, enhancing friction, and grip with the ground.

I talked about it more in: How To Improve Snow Performance From All-Season Tires?

Overall Ride Comfort

Ride quality can be assessed by two factors: the amount of noise a tire produces on the road, and its ability to smooth out surface irregularities.

Let’s take a look at both one by one.

Impact Comfort

The comfort of a ride is greatly affected by the tire’s inner and outer construction.

This aspect is important because a tire with a softer structure can absorb bumps more effectively, acting as a secondary suspension for your car.

The Riken Raptor ZR A/S, with its flexible, winter-focused rubber compound, performs well in this respect. Its tread is designed to remain pliable in winter conditions, which inadvertently enhances road cushioning.

Additionally, the tire features a very pliable internal cap ply, specifically engineered to absorb road bumps while maintaining stability and durability.

Note: Although softer tires offer considerable comfort, they tend to wear out faster. Manufacturers must strike a balance between comfort and durability. In the case of the Raptor, its primary focus is apparent, which limits its tread longevity.

Noise Comfort

Fundamentally, tire noise is a result of air particles striking against the tread walls.

However, since most air particles enter through the shoulder voids, the Riken Raptor ZR A/S, with its densely packed lugs in this area, ensures impressive overall road quietness.

Additionally, the tire’s advanced pitch sequencing tread design effectively manages the air particles that do enter.

This involves subtly varying the geometry of the lugs so that air particles striking them from different angles produce varying tones, which in turn neutralize each other’s frequencies.

Tread Longevity

The lifespan of a tire’s tread, hinges on a delicate balance between rolling resistance, tread depth, and the composition of the rubber.

The reason for this is that, tires made of stiffer rubber are more resistant to wear, and the tread depth indicates how much rubber must wear down before reaching the replacement threshold.

FYI, in US, this threshold is 2/32″, which is the legal tread depth limit allowed.

Now, the Riken Raptor ZR A/S falls short in this regard, where its softer rubber compound, designed with winter traction in mind, tends to wear out relatively quickly.

Additionally, its slightly heavier weight, compared to others in its category, also contributes to faster wear. It stresses down on lugs with greater force, causing them to rub against the road with increased friction, lowering tread longevity.

That’s why it makes sense why this tire doesn’t offer any treadwear warranty.

Side Note: The tire’s reduced tread life is the only reason, why it couldn’t make it to my list of top UHPAS tires, as a budget pick. Instead, the Fuzion UHP Sport AS took its place.

Fuel Efficiency

Fuel efficiency is closely linked to a tire’s rolling resistance, which is mainly influenced by the weight of the tire, and the composition of its tread.

The softer rubber composition of the tire, while advantageous for grip, results in greater flexing of the tire’s lugs, which leads to greater rolling resistance, necessitating more energy (and consequently more fuel) to maintain control/speed.

And that’s exactly what’s going on with Raptor ZR A/S.

I mean, the Riken is not only softer, it’s heavier weight stressing out the lugs, exacerbates the overall bending/flexing of its tread.

This leads to extra energy expenditure, where its wasted in reshaping of the deformed tread, and in the form of heat, instead of propelling the tire.

So like the tire’s wet traction, its fuel economy is also one of the most lacking features.

Wrapping Up

In summary, this Riken Raptor ZR A/S exhibits diverse performance outcomes, and choosing it depends largely on your individual driving needs and circumstances.

Its dry performance is excellent, with superior directional grip and braking efficacy, though, its handling is compromised by voided-up shoulder lugs, affecting lateral grip.

In wet conditions, the tire struggles with hydroplaning resistance and wet traction due to limited siping and groove effectiveness.

Though it still performs above-average on snow, despite lacking with Tri-peak rating.

Other than this, the tire offers a comfortable ride with reduced noise and good impact absorption, but this comes at the cost of reduced tread longevity, as its softer rubber compound wears out faster.

And yes, its fuel economy is also not that impressive.

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