In their 20th May 2015 edition, Motorcycle News put the latest crop of track day tyres to the test against the revamped Metzeler Racetec RR K3.
Courtesy of Pirelli/Metzeler, Bruce Dunn lapped a sunny Jerez circuit on a BMW HP4, with the ABS disconnected on six sets of hoops to see how they compared.
The Racetec RR K3 came out on time in terms of lap times, narrowly beating the new Battlax RS10 from Bridgestone into 2nd place by two tenths of a second. Bruce gave his opinion on the tyres he tested as follows:
1. Racetec RR K3 – Metzeler
“These Racetec RRs feel good straight away and have neutral steering. They warm up quickly and give enough confidence just after one lap to let you push. After two laps they’re ready to be pushed even harder.
There’s no movement from the back tyre, even hard on the power. The front gives you confidence to make precise and accurate turns and enough feel to trail the brakes deep into turns – traits usually reserved for full on racing tyres. High-speed stability is excellent, even under the HP4’s brutal acceleration through the gears.”
2. Battlax RS10 – Bridgestone
“These immediately give the bike a really good feel. Even on the out-lap the steering is neutral and nicely damped. Once warm the front tyre gives an almost overwhelming sense of grip and feel and the confidence to run from kerb to kerb. Feedback is so good in the high speed spections (80mph to 130mph) the tyres allow me to put the bike wherever I want, to the millimetre.
The rear doesn’t move under acceleration, even giving it full throttle exiting the corner onto Jerez’s fast back straight. Acceleration and hard braking stability are excellent. They give the rider lots of confidence, which helps maintain mental and physical output.”
3. Diablo Supercorsa SP – Pirelli
“Even on my out-lap the Supercorsas give good feel and I can progressively increase my speed, then after just two laps I can push as hard as I need to test the rubber. The steering is light and neutral, but not too flighty, even at high speeds and the Supercorsa SPs are predictable in all the corners.
They’re most impressive at high speeds, particularly entering fast corners. The front tracks accurately and takes noticeable less rider input to turn than its rivals. Some rivals suffered high speed stability issues, particularly in hard acceleration zones, but the Pirelli is faultless. They keep the bike stable and predictable at all times.”
4. GP Racer D211 – Dunlop
“First impressions are that the Dunlops make the HP4’s steering feel really light, much more noticeably than the rest and they have the characteristics of race rubber, particularly the feeling from the front. They’re extremely quick steering and let you make rapid direction changes.
They warm up fast, give good feedback, and from the second lap it’s possible to get up to speed quickly. Once up to testing speed the D211GPs shine in high speed turns. They give you loads of confidence and a stable, planted, grippy feel. A side-effect of all this agility is an occasional loss of high speed stability (80mph – 150mph range).”
5. ContiRaceAttack Comp – Continental (compound not stated, but we would expect it to be the Endurance version which falls into the same category as the K3)
“The Contis give good feel straight away. The warm up and scrub-in is predictable and impressive, and after two laps they’re ready to be pushed. The corner onto the back straight is a test of nerve and requires utter confidence in your tyres. Here you’re opening the throttle in fourth gear to a blind apex at 45 degrees of lean. Even here the feel from these tyres is excellent and encourages you to ride with more gusto.
Stability is good under acceleration and during rapid direction changes. But on the flip-side, braking and turning-in require a lot of rider efort. I often find myself running wide because the tyres don’t turn in as fast as I’d expect. But it’s a good tyre and far superior to Conti’s previous product.”
6. Power Supersport – Michelin
The Michelin Power Supersport came last in the test, 2.4 seconds behind the Continental.
However, Michelin have just released an upgraded EVO version of the tyre, which has replaced the original. This new version was not tested, but promises improved grip and stability, thanks to the latest compounds and Adaptive Casing Technology from the French firm.
