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variable valve timing

In an era marked by the anticipation of the internal combustion engine’s demise, Italian manufacturer Piaggio is breaking new ground in engine development.

  • Despite the ongoing shift towards electric power, Piaggio is focusing on enhancing the efficiency of small, low-cost engines for scooters.
  • The company’s latest innovation is a Variable Valve Timing (VVT) system designed specifically for these engines.

Piaggio’s VVT system, outlined in a detailed patent application, aims to optimise the intake timing on single-cylinder, single-overhead-camshaft engines used in scooters. Given the tight profit margins in this segment of the market, the design emphasises simplicity and reduced component count.

At first glance, Piaggio’s SOHC VVT system appears similar to Yamaha’s “VVA” (Variable Valve Actuation) design used in various motorcycles. However, a subtle yet crucial difference sets Piaggio’s system apart.

Both systems employ two profiles for the intake cam lobes, which act on a forked rocker arm to control two intake valves. Like Yamaha’s VVA, Piaggio’s system uses a pin to connect or disconnect the rocker arm, with an actuator to engage it and a spring to disengage it when not needed.

The key distinction lies in the number of elements in the rocker arm. Yamaha’s VVA system features two parts: one conventional rocker and one element for high-lift, long-duration cam lobes. In contrast, Piaggio’s design incorporates three elements in its rocker arm, allowing for more comprehensive control over valve timing, lift, and duration.

This innovation enables the Piaggio system to adjust not only valve lift but also timing, offering a distinct advantage over Yamaha’s system, which can only switch between low-lift, short-duration and high-lift, long-duration lobes. With Piaggio’s design, the high-rpm cam lobe can have different timing, enhancing engine performance at high revs.

The patent showcases this system on an engine that resembles the Vespa GTS 300, utilised in various Piaggio models, including the Piaggio MP3. Piaggio’s commitment to improving small-engine efficiency reflects its dedication to innovation in an ever-evolving industry.

Hold onto your helmets, folks, because BMW might be gearing up to release a serious game-changer in the world of motorcycling.

  • Next-generation G 310 series to be equipped with BMW’s ShiftCam technology. 
  • The ShiftCam system will boost the bike’s performance and fuel efficiency. 

The German automaker has just filed a patent application that hints at a potentially groundbreaking development: a ShiftCam-type variable valve timing system for a single-cylinder engine. And if the rumors are true, this could be a major step forward in terms of efficiency, power, and emissions reduction.

The patent, which was filed in August 2021 and published by the German patent office on February 16, 2023, reveals that BMW has been working on a valve actuating system that can control the timing and lift of one or more valves simultaneously. By connecting multiple cam pieces, or using a single cam piece with multiple contours, the system can deliver enhanced performance across the board, from improved power and torque to better fuel efficiency and reduced emissions.

The implications of this technology are huge, especially for BMW’s G 310-series of motorcycles. With a more compact design and a weight-saving valve train, these bikes could potentially offer even more agility and responsiveness on the road. And by incorporating two or more actuation profiles, riders might even be able to customize their riding experience based on their individual preferences or the specific demands of their chosen terrain.

Of course, BMW has yet to make any official announcements about the new technology or its plans for integrating it into future models. But given the company’s history of innovation and its commitment to sustainability and efficiency, it seems likely that we’ll be seeing some major updates to the G-Series and other models in the near future.

BMW Motorrad didapati telah memfailkan paten terbaru pada Ogos 2021 yang jelas memaparkan sistem ShiftCam pada enjin satu silinder. 

Berdasarkan paten tersebut, sistem ShiftCam itu akan membantu mengurangkan berat, meningkatkan tahap efisien penggunaan bahan api di samping memperbaiki kuasa dan tork enjin sama seperti teknologi ShiftCam yang terdapat pada enjin Boxer ketika ini. 

Ini bermakna terdapat kemungkinan besar jentera satu silinder seperti BMW G 310 R, G 310 RR dan G 310 GS akan dikemas kini dengan sistem ShiftCam tidak lama lagi.

Buat masa ini tiada pengumuman rasmi daripada pihak BMW mengenai perkembangan terbaru ini namun mengambil kira BMW sering menaik taraf jentera sedia ada, tidak hairanlah jika sistem ShiftCam ini akan direalisasikan pada enjin satu silinder dalam masa terdekat ini. 

JIka benar, maka kemungkinan besar generasi seterusnya BMW G 310 akan mendapat naik taraf yang signifikan. 

Aprilia is set to join the likes of Ducati, Yamaha, Kawasaki and Suzuki by introducing its own variable valve timing (VVT) system as confirmed by latest patent application submitted by parent company, Piaggio Group. 

The patent – based on the Aprilia RSV4 – showcased a non-electronic VVT system that works similar to Suzuki’s GSX-R1000 whereby the system depends on centrifugal force to move the ball bearings located on the drivel wheel of the intake camshaft. 

However, while the GSX-R1000 VVT works on 12 ball bearings, the upcoming RSV4 will used only three. 

Despite that, we expect the system to worked well similar to any VVT technology available on modern two-wheels.

That said, Aprilia is working on a mechanical-based VVT as compared to electronics, currently adopted by Ducati, Kawasaki and Yamaha. 

However, the new system could also be applied to other Piaggio-owned brand, including Moto Guzzi. 

  • Indian Motorcycle patented their variable valve timing (VVT) system.

  • It will equip a new Euro 5-compliant engine.

  • The technology is the best solution in delivering power with low fuel consumption and emission.

More and more manufacturers embrace variable valve timing technology as Euro 5 looms. Indian Motorcycle is next up.

As Euro 5 seeks to cut more emission, motorcycle manufacturers are forced into looking for other solutions. It was either that or downsizing the engine or reducing power production (god forbid!).

Right now, VVT offers the best answer. Variable valve timing and variable valve lift controls valve overlap at the correct engine loads and timing, yielding power while saving fuel and limiting emission at the same time. Please click the link below to learn more about variable valve timing/variable valve actuation.

2019 Ducati Diavel 1260 to Feature DVT

VVT usually finds place in motorcycles with “sportier” deposition such as the BMW S 1000 RR, Suzuki GSX-R1000, it’s made its way into other types of motorcycle engines. Ducati uses their proprietary Desmodromic Valve Timing (DVT) in the 1260cc V-Twins, while Yamaha employ the tech in their scooters. BMW has now equipped the new 1254cc Boxer (flat-twin) with their own “ShiftCam” technology.

Photo credit – United States Trademark and Patent Office, Motorcycle.com

A new Indian engine was spied months back, but patents revealed that the American manufacturer is pursing VVT technology as well.

Indian’s VVT looks different in because the engine employs overhead valves (OHV) and pushrods rather than overhead camshafts (OHC). Therefore, the VVT phaser is situated at the of the crankcase.

  • Suzuki tampak sedia untuk menggarapkan sistem pemasaan injap boleh ubah (VVT) baharu pada model GSX-R1000 baharu mereka.
  • Sistem semasa menggunakan daya emparan.
  • Sistem baharu ini mengikuti trend semasa menggunakan VVT yang diaktifkan secara hidraulik.

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  • Suzuki looks poised to install a new variable valve timing system in the new GSX-1000.

  • The current system uses centrifugal forces.

  • The new system follows the trend of using hydraulically-activated VVT.

The current Suzuki GSX-R1000 is already employing variable valve timing (VVT), but the new generation will feature a newer VVT.

As of now, the Suzuki GSX-R1000 VVT technology is derived directly from the Suzuki GSX-RR MotoGP bike. MotoGP regulations forbid hydraulic, electric and electronic variable valve timing and variable valve lift systems. Hence, Suzuki worked around this restriction by designing and employing a mechanical solution since 2015. The system works by using centrifugal force generated by the camshaft as it spins.

However, Suzuki has submitted the patents for a “traditional” hydraulically-activated system for the road bike. According to the documents, it is an oil pressure-activated, cam-shifting system.

Like the VVT patents of Honda, Suzuki’s VVT will activate both intake and exhausts cams. The current Gixxer is great to ride, but there are limitations of the current VVT due to the weight of the springs and gyroscopic forces in the mechanism.

It is also different from the BMW S 1000 RR’s ShiftCam system.

We foresee more motorcycles will be fitted with VVT systems of sorts in the years to come. As we mentioned before, VVT is one of the best ways to combat exhaust emissions and fuel consumption while still providing loads of power.

  • Honda telah memfailkan paten bagi teknologi ‘variable valve timing’ (VVT) baharu mereka.
  • Adakah teknologi ini bakal dilengkapkan pada model CBR1000RR Fireblade baharu mereka?
  • VVT menawarkan kuasa dan juga pematuhan kepada piawaian emisi.

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  • Honda filed for a patent for their new variable valve timing technology (VVT).

  • Could this be fitted to the new CBR1000RR Fireblade?

  • VVT offers both power and adherence to emissions standards.

Honda filed for a patent for a new variable valve timing (VVT) technology recently. Could it be for the new Honda CBR1000RR Fireblade most probably due in 2020? Or could it be fitted over other ranges of models, as well?

Honda’s new VVT system is akin to the BMW ShiftCam system which switches cams.

Each cylinder is fitted with two distinct cam lobes, one for low revs and another for higher revs. Like BMW’s system, the camshaft is slid back and forth to allow the appropriate cam to act on the finger followers, which in turn push open the valves. However, Honda’s system differs by having the system on the exhaust cam, as well.

This new system is different from Honda’s own iconic Variable Valve Timing & Lift Electronic Control (VTEC). It engages or disengages one set of cam lobes depending on engine load, whereas the new system’s cam lobes all spin at the same time.

Variable valve timing technology is not new in the world of motorcycles. As emission standards become tougher while the demand for more power grows at the same time, VVT is the only way to go. (Please click here to learn more about VVT and DVT.)

Almost all manufacturers employ VVT technology nowadays, although it is starting to be a trend among sportbikes. Heck, even the Yamaha N-Max, NVX and X-Max scooters feature VVT.

But it was Honda who first introduced VTEC to the in the 1989 Integra. It took another decade before it was adopted by the Honda CB400 Super Four VTEC in 1999. Since then, the Ducati Multistrada 1200 and its successor the Multistrada 1260, Kawasaki 1400GTR, Suzuki GSX-R1000 employ one form of VVT or another.

All-new Ducati Monster 1200 R officially teased – slated to become Ducati brand’s most powerful naked bike ever.

(more…)

Ducati-testastretta-DVT-Desmodriomic-valve-timing-14

New Ducati Testastretta DVT engine technology revealed, 2015 Multistrada will adopt it first.

(more…)

ducati-superquadro-motor-5

Ducati set to introduce new engine with ‘DVT’ variable valve timing (VVT) technology this month.

(more…)

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