Honda's new Pan European- and Blackbird-replacing V4 can run as a twin, triple or V4, not just the parallel twin and four-cylinder modes expected, MCN has discovered.
The latest news emerged from Japan where the final intensive stages of testing are in progress. Honda engineers and testers have been particularly hard at work ensuring the engine has the expected Honda level of durability when running in triple mode, when the engine's cylinder banks are running unevenly, placing higher levels of strain on the motor.
Testers have revealed the three modes of running are essential to ensure a smooth transition in performance from economy twin-mode to full-bore V4.
It also allows the optimum power and character for a wider range of riding situations. The transitions depend on the operation of the throttle and have been honed for the past two years in Japan on a variable V4-engined Blackbird mule.
The result is a motor which feels "Very, very special" according to one Japanese tester. "Engine has more character than R1, more than other Hondas, it will surprise many people" he added.
We can also confirm the Pan European replacement version of the V4 will have a Porsche-style double-clutch gearbox, that again is more sophisticated than previously thought.
The dual-clutch system allows the box to run in three bar-selected modes - Drive, Manual and Sport. Drive gives full control of gearchanges to the bike, changing up early and encouraging it to stay in twin and triple modes longer to eke out the economy.
Manual allows the rider full control of changes, but uses the twin clutch set up to anticipate which gear is coming next, pre-selecting the next cog to make the transition as fast as any quickshifter and smoother too.
Sport is the most radical departure of all for a sporting Honda, again leaving shifts in full control of the bike's ECU but hanging onto gears to wring the maximum acceleration performance from the motor, while allowing the rider to concentrate purely on throttle and steering.
Testers say Sport mode is eerily accurate in its anticipation of the right gear change and the allows for faster cross-country riding for even experienced riders. MCN Senior Road Tester Michael Neeves recently praised the continuously-variable transmission on Aprilia's new Mana GT, saying that having the intelligent automation of gear selection on a bigger-capacity sports-oriented bike would make it the ultimate A- and B-road tool. Honda's new V4s are shaping up to be just those bikes.
First V4s just the 'tip of the iceberg'
The first V4s - the sports-tourer and Pan European/Blackbird-replacement scooped by MCN - are 'just the tip of the iceberg' according to project engineers. Hinting that V4 power will be at the heart of a generation of machines from Honda, MCN's Japanese source revealed the firm is working on a dynasty to overshadow even that of the iconic Fireblade.
"When we first launched the Fireblade in 1992 we had a plan that stretched as far into the future as the 954cc version of 2002. It's the same with the V4s. There are many branches to the family."
MCN's source also revealed that when the running with less than the full four cylinders, the deactivated pistons don't run as air springs. Instead the non-firing cylinders contain a vacuum, which resists the piston on the downstroke, but sucks it back up the bore on the upstroke, lending acceleration to the crank on the active cylinder's power-stroke.
The engineer was also keen to point out that the V4 enjoys the same much-praised crossplane effect as the R1. "Yamaha would have built a real V4 if they thought they had the experience to do it.
The V4 has the crossplane crank inherently. When people ride the bikes they will be amazed by the character and usability of the power" he claimed.