RSR ORCA Tachometer

Typical "custon" digital tachometers do next to nothing except take your money and give you something to polish. They are hard to read....because that's what you have to do, you must "read" the digits. There are no shift lights, no 12 o'clock redlines. They are usually part of a display where you have to take your eyes off the road to read them. Not exactly something for a high horsepower application. It is nice to polish however.

Situations Define the Problem

When we started building really high horsepower ORCA turbo engines we had trouble watching a tach, the boost gauge, our RSR Air Fuel Ratio Gauge, egt gauges, the road, cars or the racetrack. We often would overshoot our redline with a slow-acting air core or stepper motor tach with a mechanical needle. More often than not the tachs would vibrate themselves to death.

The rider did everything by feel but without some recording capability we might know the bike hit 25 psi but the peak rpm on the run might remain a mystery. RPM, boost, air fuel ratio, egts, voltages...it's a lot to remember without recording things.

Customers would bring us bikes with big face 5" automotive tachs that had needles in a permanent vibration blur...patently useless. They also blocked your view when you tried to crawl under the paint.

Steve Manley..Racer / EE

While we know what we want, we also know when to get help in electronics and embedded system design. Steve Manley, the principal of xdesignlabs, has spent way too much time fooling with digital tachometers and race car engineering issues, in-between flying around serving his growing base of racing and industrial clients... So we mixed our special requirements with his expertise and came up with the Orca Tachometer. We did the final circuit layout work, machining and mechanical design and Steve provided the circuitry and embedded code.

It takes a racer to understand racing. We race on two wheels and he races on four. The requirements are different but the ideas are the same.

In Canada all open wheeled race cars are required to have snow plows. Steve did a complete ground-up rebuild of this Reynard. You can view the process on his website.

Continued Prototype Testing

We tested all sorts of combinations of l.e.d.'s.including blue, orange, red, green, yellow. Certain colors imply things. You have to run the tach in the real world to see how you integrate with it as a system. If there are any hestitations or distractions it's time to try another scenario.

Testing on bikes has resulted in finalized size, color sequences, and brightness levels. It has proven to be the best tach we have ever used. Way, way, better that anything else. The above picture shows two prototypes ( not final configuration) being tested on a BMW motorcycle and on a test bench.

Testing at Bonneville

Flickering seven segment L.E.D.s don't always register in a digital camera. Here the memory function (blue button) in the tachometer, to the left, was showing the rider hit a peak rpm of 6800 rpm somewhere on the course. The GPS Speedo, to the right, is showing a peak speed of 183 mph (3rd gear) during a test run.

FXR Test Vehicle

We like FXRs and we instrumented ours with our digital Tachometer, GPS Speedometer, Dual O2 Gauge and Gear Indicator. No it's not a FLHX. It started out as a 1999 FXR CVO2 that we put on a 5 gallon FL tank and got rid of the solid rear wheel and the 21" front wheel. We also converted it to chain drive and put on a Hayabusa steering damper and one ot our LSR 2-1 1 3/4" B Style turn out exhausts. We also fuel injected it with one of our closed-loop RSR Injection Systems.

We had Jim's Cycle painting put on a simple one color scheme as the cops seemed to be attracted to our blue tank, yellow rear fender and purple front fender. Clown bike. Painters are weird. We just left the color up to Jim. He painted Seven time F1 Champion Michael Schumacher's Bobber Harley. Jim died in 2012 of a heart attack.

Final Version

We tested all sorts of combinations of lights, silkscreens and color schemes and this is the final product. It is a hard anodized billet enclosure with a laser cut stainless steel faceplate that has been optimized for brightness and has a textured and coated surface to prevent unwanted reflections.

It is the world's best tachometer that functions as a shift light and provides no-lag readings of rpm in 50 rpm increments. Easily visible under hard acceleration.

0-9999 rpm bright yellow digits with 50 rpm increments . Sixteen L.E.D. colored lights. 500 rpm per step. Full scale on the 16 l.e.d.s is 8000 rpm.

Two yellow lights for idle below 1500 rpm. Five green lights for normal operating range i.e. below 4000 rpm. Five orange lights, the first of which indicates a 4000 rpm shift point. The last orange light indicates 6000 rpm. Four red, the first of which is at the twelve o'clock position indicating a redline shift point of 6500 rpm.

Blue button is high recall for both sweep and digit scales. White button is brightness select for daylight or nightime. Red button is reset, or zeroing, of the high memory recall. Buttons are high force and are easily operated with gloves.