An insider’s look at Aprilia Performance Ride Control

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Once we’d started putting together a series of videos on the new Aprilia RSV4 APRC, it became quickly apparent that we needed to develop an intimate understanding of how Aprilia Performance Ride Control worked if we were going to stand a chance of doing it justice. Aprilia may have developed the most sophisticated set of performance enhancing electronics ever in-house, but, in typical Italian fashion, there was no cohesive document explaining its function. Definitely not one written in plain English. So, Grant, Aprilia USA and I set about poring over inches-thick, proprietary technical manuals and service guides, sending questions to Italy to check our conclusions. The result is this document, originally created strictly for internal use only, but reprinted with permission here. Not to brag, but it’s the most definitive explanation of APRC ever created.

Aprilia Performance Ride Control Explained

All of the APRC systems work together to produce quicker lap times. Aprilia Launch Control gets you off the line faster; Aprilia Quick Shift lets you get up to top speed faster; Aprilia Wheelie Control lowers the front end under hard acceleration and out of bends; Aprilia Traction Control lets you explore cornering limits with 8 levels of sensitivity.

Components: front and rear wheel speed sensors; ride-by-wire with three switchable maps; joystick control; +/- buttons; instrument display; two gyroscopes (one lean, one attitude), two accelerometers (acceleration and turn); ECU; gear position sensor, throttle position sensor, pressure sensor on shift lever.

Aprilia Traction Control (ATC)

Process: The rider presses the mode button and selects the desired level (1-8, 8 being most
intervention) using the + and – buttons. Each level contains a minimum and maximum slip threshold.

While riding, the speeds of the front and rear wheel are constantly compared, alongside parameters for the roll angle and longitudinal acceleration. Depending on the TC level selected and upon exceeding the minimum slip threshold for that level, the Traction control system enters a control state. The APRC light flashes rapidly when ATC is limiting torque. The rider is then able to modulate slip up to a maximum threshold, a point which cannot be exceeded. As the bike becomes more upright, a higher degree of longitunal slip is allowed by the system.

The ECU reduces torque accordingly in two different ways – “partializing” throttle valves (gentle) and reducing ignition spark advance at the coils (hard). The ATC system primarily reduces torque through the throttle valves.

Effect: Rather than a severe cut to limit acceleration and reduce rider control, the ATC’s logic allows a significant degree of rider control within specified slip parameters. Even while the system is limiting torque, the rider can effectively work within a range – modulating the throttle for more slide or vice versa. The system is constantly re-evaluating, so if you’re power sliding out of a corner, the more upright the bike becomes the more slip is allowed. Maximum acceleration is achieved with a limited degree of rear tire slip, which enables the rider to more to fully exploit the bike’s performance potential safely.

Aprilia Wheelie Control (AWC)

Process: The Wheelie Control is able to determine when a wheelie begins and ends. Due to the
accelerometer, AWC can actually determine when a wheelie is occurring rather than involuntarily reacting to differing wheel speeds. Wheelies are thus controlled much more smoothly. Using the mode button and + /- buttons, the rider selects AWC from one of three levels (3 being the most conservative).

Acceleration data from the accelerometer and relative speed between front and rear wheel is compared to determine conditions for a “wheelie.” If a wheelie is detected, traction control is momentarily disabled and the length of the wheelie is controlled by limiting torque via ignition advance and throttle valve aperture, just like ATC. Level 1 allows longer wheelies and level 2 and 3 shorter wheelies. Even with the Wheelie control turned off, the Aprilia traction control is still active as long as the front wheel is in contact with the ground. With the wheelie control turned off, the ATC system allows a wheelie for 30 seconds and inhibits a wheelie if the roll angle exceeds 25 degrees.

Effect: Wheelies become a separate variable from TC in the ECU. This is especially useful while
cornering, where front wheel lift could cause the bike to run wide, yet over-harsh correction could limit performance. Instead, the bike holds the front wheel on the ground while permitting maximum possible acceleration.

Aprilia Launch Control (ALC)

Process: Rider selects one of three levels using the mode button and +/- buttons; 1 is the fastest launch level. ATC and AWC are disabled for start, but traction and wheelie control is handled by unique programming when Launch Control is enabled. Rider holds the throttle fully open while the ECU maintains a constant 10,000rpm (levels 1 and 2) or 9,500rpm (level 3).
To launch, rider simply holds throttle open while feeding out clutch. During first phase of launch, wheelies are PREVENTED with ignition advance while a variable rev limit is applied, allowing more revs as speed increases. Once the clutch is fully engaged a limited degree of wheelie is permitted. Once the bike crosses 100mph and a gear higher than 2nd, ALC disengages and AWC and ATC automatically reengage at their previously set level.

Effect: Race starts become accessible to less-experienced riders and predictable for experts.
Maximum possible acceleration is achieved thanks to wheelie control in conjunction with the Aprilia Launch Control. The ALC is the only launch control system on a production bike.

Aprilia Quick Shift

Process: Rider holds throttle wide open, doesn’t use clutch. Pressure on the gear selector is detected, triggering the system to evaluate throttle map, throttle position, gear position and acceleration – ultimately determining the speed of the shift. Torque is cut by reducing ignition advance and injection times, enabling the next gear to smoothly engage. Torque is then gradually fed back in to smooth the shift.

Effect: Upshifts are completed without closing the throttle or disengaging the clutch, making them faster and limiting RPM loss. The rider can snap home instantaneous shifts on track or smooth, easy shifts on the road.

You can watch the videos that resulted here.

  • Lacubrious

    Dang yo. What’s it like switching back to a lay bike after ride that cylon?

    • http://hellforleathermagazine.com Wes Siler

      It feels a bit lame once you switch back. Even relatively mundane stuff like the quickshift is executed really well and just works so damn smoothly. It’s pretty damn neat using a quickshifter during mundane, day to day street riding.

  • BMW11GS

    S1000RR and Aprilia showdown! before you say “we dont to comparos”, I would be interested to see which manufacture does a better job at translating this technowizardey into street performance. Go!

    • http://hellforleathermagazine.com Wes Siler

      The S1000RR has a little more top end. The RSV4 is appreciably smoother. Fast riders turn off the BMW’s tc. Fast riders love APRC.

      • BMW11GS

        hahah brilliant! okay you can tell I am biased toward BMW…but broken down like this, the RR vs RsvR dichotomy makes a lot of sense. Just when I thought I could be smug…

        • http://hellforleathermagazine.com Wes Siler

          There’s a huge generational gap between the two systems. BMW is relatively low tech and is mostly safety aid. APRC makes bike faster.

          • BMW11GS

            very concise! Thanks Wes

            • http://hellforleathermagazine.com Wes Siler

              Conciseness is my current specialty.

          • Myles

            So the order of sophistication is:

            Prilla
            BMW
            Team Green
            Duck

            Just curious, don’t really see myself with a superbike anytime soon.

            • http://hellforleathermagazine.com Wes Siler

              Aprilia
              Kawasaki
              BMW
              MV Agusta
              A tomato
              Ducati

              • Myles

                I THOUGHT YOU GUYS DIDNT DO COMPAROS LIKE THE OTHER SHITTY OLD MAN MAGAZINES!!!!

                • http://hellforleathermagazine.com Wes Siler

                  We’d love to, but don’t have enough tragically garish apparel to adhere to the formula properly.

              • Lottoboy

                Real life lolz @ “A tomato”.

    • Scott-jay

      A joy of electronics invading proper motorcycles is accessing them with a laptop.
      Just today read of privateer roadracers on BMW tuning its chassis controls for racing.

  • stefano

    can my CB200 have that installed? ;)

  • HammSammich

    My Bonneville is actually fitted with a really sophisticated Wheelie control system – HABWWR: “Heavy Ass Bike With Wimpy Rider.”

    Seriously though, this is a great explanation and I find myself in awe of the level of technology that has gone into the bike. I’m only 33 years old, and yet this bike evokes from me anachronistic phrases like “Whiz Bang” and “new-fangled contraption.”

  • http://greatjoballweek.blogspot.com/ Case

    This article sets my nerd boner to ‘stun’. Also: this bike is awesome. Just out of curiosity, did you flip it to inverted shift? How do they manage that on the bike if it comes regular shift from the factory?

  • http://www.muthalovin.com the_doctor

    Thanks Max.

  • Chris

    I can’t wait to ride one of the APRC bikes to compare it to my 2010 V4R.

  • zipp4

    Did you see the old men at Cycle World crash theirs in this month’s review? Said the chassis was unresponsive and disconnected. Funny, considering in the initial review all they did was rave about how perfect the chassis was.

    • http://hellforleathermagazine.com Wes Siler

      I’ve been told that real journalists never blame a bike for the crash…

      • Eric

        Originally they were going to put the blame on the center-stand touching down . . .

      • zipp4

        Zing!

  • Fergus

    Holy crap, I love this bike. I think the only reason I don’t get one (other than all the money!) is that I’m wondering what the Ducati 1199 will be like. The RSV4 is certainly the best sounding bike I’ve ever heard. There’s one – the APRC SE version – at an Aprilia dealer near my place and I ogle it every time I walk by. Sigh…

    • Chris

      I wonder if Ducati will carry over the 1198 into 2012 with the new bike as a flagship model at a premium price point ($23K+).

      If Honda releases a new V4 as has been speculated, it will probably be the same – carry over the CBR1000 and sell the new RCV as a flagship model… sell enough units to pass homologation for WSBK.

  • jonoabq

    So one of the questions now is as more motorcycles come with better and more seamless intervention systems there will be more riders actually learning to ride on them as first bikes. Do they still really learn how to ride or because of the rider aides are they missing something? Maybe missing something important?

    • DoctorNine

      I suspect that riders who start riding on bikes with systems like this will actually learn to ride better, because they will be able to push the limits of adhesion on slides, and use heavier throttle inputs than they would otherwise. In effect, the cost of exploring the ‘danger zone’ is less, because the electronics make a high/low side less likely. Once they get the ‘feel’ of how to ride in that zone, it should translate to bikes with no electronic nannies, but the rider would notice harsher and more abrupt transitions.

      • Nick

        Like a highside. I hear they are harsh and abrupt.

  • Terry

    Just imagine how we’ll be in another 20 years:

    “Back in my day, we had a clutch!”
    “STFU grampa!”

    • James

      Going from a scooter with CVT to a motorcycle for the first time it really did feel like I was on some old grampa technology. A manual clutch system. It’s like having to pump your own water to take a bath.

      • Liquidogged

        The timing of pulling in a clutch lever, clicking a nice crisp shift, and applying the correct amount of throttle at the correct time is one of the great pleasures of motorcycling. While I recognize how leaving the clutch lever out of the scenario is technically better, it still takes away some of the attraction.

        Goes back to my two minds on this whole system. Yes, it is better than manual everything as evidenced by lap times. Yes, it makes it easier to ride faster. I’m not sure that making it easier to ride faster is that great of a goal. Granted, that is the entire goal of performance modifications, but this is done by actively correcting user error. The bike is almost riding itself for you. Technically it is amazing, but it leaves my riding soul cold.

        • Devin

          Yeah, this is the biggest downside to maxi scooters. Plus if you are on a bike with less than 80hp or so, sometimes you just want the ability to really flog it for some extra oomph. I also live in a city with no traffic jams, so the clutch never feels like a burden.