- Published: Tuesday, 04 April 2017 16:21
Find out how Bridgestone's sporty road tyre handles Singapore's sloppy tarmac
Text: Deyna ‘Hypercrack’ Chia
Photos: Derryn Wong
SINGAPORE - The Bridgestone Battlax S21 has been available in Singapore for some months now, and we thought it a good time to give a quick on-road review, particularly on the back of our review of the Yamaha XSR 900 which came fitted as standard with the S20.
Bridgestone Battlax S21
To recap, Bridgestone terms its second sportiest road rubber for motorcycles under the label ‘hypersport’, and that’s the segment the Battlax S21 is in. The name ‘Battlax’ is a generic one for all its bike tyres, while S ostensibly stands for ‘sport’. Above the S21 are the RS10 ‘Racing Street’ tyres, and below the S21 are the T20 ‘Sport Touring’ rubber. The RS10 competes with Pirelli’s Diablo Supercorsa SP and Rosso Corsa in the track/extreme sporty region, with the S21 competes with the Pirelli Diablo Rosso III (also tested in the next article).
Over the past decade, the hypersport model for Bridgestone went from the BT-016, BT-016 Pro, S20 and S20 Evo, each bettering the previous model in varying degrees, as noted in our tests of both the S20 Evo and S21 on track previously.
The S21 showed off superior on-track performance conspicuosly improved from its predecessors
At the international debut launch of the S21 in Yas Marina, Abu Dhabi last March, we found the tyre to be excellent on track, with the various improvements doing a great job of upping the ante in tyre performance.
We won’t list them again comprehensively, but in summary: Bridgestone has leveraged on proprietary ‘U-EYE’ testing facility, and made big changes to the following: compound, tyre crown profile, belt position, groove pattern and positioning, and more.
The question that remained, and which we answer today is: How does the S21 perform on Singapore’s roads?
We covered about 250km with the S20 and S21 respectively. The S21s were a broader profile in the rear, 190/55 instead of 180/55. The first thing we noticed with the S21s was how sporty the tyres felt, much stiffer tyre walls (particularly) in the rear, showing up the weakness in the XSR's suspension, resulting in a less comfortable and at times jarring ride. It felt like the tyre profile (wall height) had been reduced by five to 10 percent.
190/55 R17 as fitted to the Yamaha XSR 900 test bike
Taken through our usual test route of chicanes, roundabouts, sweepers and monotonous highway commutes, the bike felt a little slower to turn, though more stable whilst leaned on its side. Like the S20, the S21's dry performance far exceeded the demands of commuting, even with the occasional spirited riding. Even in the rain, the S21 felt sure footed, and only ham-fisted throttle application over wet lane-divider paint strips would cause a momentary stutter, but nothing to concern the seasoned commuter.
The stiff tyre walls also aided braking stability, responding well to firm lever pressure without the "squish" comfort-biased tyres sometimes yield. This however did show-up the softly-suspended front end of the XSR, which could potentially cost a perfectionist owner a lot - by ploughing out money for any number of fork upgrades.
With the Hypersport label, the S21 is meant for litre-bikes or powerful sports tourers. The tyre impressed at Yas Marina, but for daily commutes, we'd say the S21 was perhaps a tad too sporty for a street-bike with an all-round focus like the XSR 900. To put things in perspective, Bridgestone deems the S21 is suitable for the 200hp, 266kg Suzuki Hayabusa and 199Hp, 205kg BMW S1000RR, whilst the XSR produces 115hp and weights just 195kg. To use a car analogy, it’s like fitting 18-inch, low-profile sports rubber to a Toyota Corolla Altis. There’s nothing wrong with that of course, but just be prepared to make some sacrifices for performance’s sake.
We didn’t have the time to do long-runs with the tyre, but Bridgestone claims an increase of tyre life by more than 30 percent. We caution that this is very subjective and rider/machine dependent, but it seems true that the S21 is indeed quite an enduring tyre. A close riding associate of ours has eked out 9,000km from a set fitted to a liquid-cooled BMW R 1200 R used for commuting, B-road rides and touring up north. Suffice to say the tyres were not pampered and were well used.
Our friend with the R 1200 R, he's replaced his worn set of S21 with.... another pair of S21. No surprise really: We maintain that it's a performance tyre which easily ticks all the boxes for a sport tyre, with superb grip, good longevity and excellent wet weather handling. For under SGD $300 (including GST, excluding fitting) for a pair (120/70 R17 front; 180/55 R17 rear), it’s truly compelling.
The S21 is distributed by Everfit Motor Pte Ltd (Bridgestone’s Singapore wholesaler for motorcycle tyres) in the following sizes and prices, without fitting:
120/70 R17 $104
180/55 R17 $163
190/50 R17 $166
190/55 R17 $171
160/60 R17 $148