Valentino Rossi and Jorge Lorenzo have made it clear to Yamaha that a seamless shift gearbox could drastically help improve acceleration issues with the new 2013 factory YZR-M1.
A new gearbox was high on reigning world champion Lorenzo’s wish list for 2013, but the seamless shift system already employed by Honda and Ducati is not yet available.
And both Rossi and Lorenzo admitted at the end of the second day of MotoGP testing in Sepang today that they have no indication when Yamaha will introduce a seamless shift gearbox.
It is not even clear if the Japanese factory plans to introduce the seamless shift gearbox, which Honda and Ducati have been using since 2011.
Although both claim the seamless shift gearbox only gives a minimal advantage of 0.1s per lap, it is the stability under acceleration when shifting up through the gears that offers an improvement over the current Yamaha system.
A rear pumping issue under acceleration remains a key weakness for Yamaha’s YZR-M1, and both Rossi and Lorenzo spoke about how a new gearbox could help when asked by MCN in Malaysia earlier today.
Rossi told MCN: “The important area is acceleration, because it looks like the M1 is very good until the acceleration part where it’s good, but looks like if we try to use more power the bike pumps, wheelies, and goes a bit in crisis. I never follow the Honda with the Yamaha.
But last year when I followed the Honda with the Ducati and the Yamaha, the difference in acceleration was quite big. It looks that Honda is able to put more horsepower on the ground, but not because they have more horsepower but because they can use some horsepower more than us. It is better mechanical grip.”
Rossi believes a seamless shift gearbox would go some way to alleviating the pumping problem under acceleration and after finishing fourth quickest for the second day in succession in Sepang, he added: “A seamless shift gearbox could make the difference but for me, more than the first part of throttle opening, it is the second part of the acceleration when you go full throttle that the pumping comes.
A seamless shift gearbox is very good and it is an advantage for sure. I am pushing on Yamaha for this gearbox but I don’t know. We don’t know if arrive or not. We hope so."
Spaniard Lorenzo, who finished second behind Repsol Honda rival Dani Pedrosa for the second day in a row, appeared disappointed that his repeated requests for the seamless shift gearbox throughout last season has not delivered a new system in time for the start of winter testing in Malaysia.
Lorenzo set a best time of 2.00.568 today to finish just 0.019s behind in-form Pedrosa and he told MCN: “We still have this movement on acceleration, the pumping, and we still haven't solved this.”
Asked by MCN if he was disappointed a new gearbox did not form part of Yamaha’s new 2013 YZR-M1, he said: “Yes, of course it is better to have this gearbox rather than not, it makes some difference on acceleration on the long corners and on full throttle and upshifts.
But for the moment we don't have it and we don’t know if the regulation will change and this gearbox will be forbidden in one or two years. I don't know. Lucky we have some other strong points like the braking for the high-speed corners but when we pick up the bike we need to improve it.
We are working on it but it seems that the Honda guys don't have to take so many risks in the corners, just pick up the bike and they have something more. But it is opposite on the braking where it seems we are stronger. But finally in lap times we are quite competitive."
The status of Yamaha’s seamless shift gearbox plans will become clearer tomorrow when senior engineer Kouichi Tsuji holds a special press briefing with the media at the Sepang track.