So I'm looking at my exhaust valve actuator thing on top of the airbox, and I'm wondering if it can be overridden with a switch or something to make the exhaust louder when you want it louder. Like at lower rpms or idling at a stop light. I envision possibly a switch mounted on the handlebars that can be toggled to open the exhaust at times when you may want a throatier growl without having to completely floor it. The only time I see it open is when it's completely gassed. Might be fun to have it controllable so that you can increase exhaust volume on demand.
I know it might trigger a temporary CEL while overidden, but other than that, is there a substantial reason this is a bad idea?
Doug, I have a toggle switch that has 6 pins. The white wire from the valve's servo to the ECM is cut and hooked to it. Along with a ground wire. Let me see if I can get this right.
I used three of the pins on the switch. We will call them 1., 2., and 3. 1. is the white wire from the ECM 2. is the white wire from the servo 3. is wired to the ground
When the switch is to the right it closes 1. and 2. This has 2. and 3. open Valve will operate as the OEM intended.
When the switch is to the left it opens 1. and 2. This has 2. and 3. closed Valve will stay open as long as the white wire from the servo is ran to ground instead of to the ECM. After 5 seconds the CEL will light up. 5 seconds after the ECM is reconnected the light will go out. This has worked for me. But I offer no warranty. On an interesting side note, with the race ECM, a cold engine, and the valve forced open: a quick opening of the throttle stands my bike straight up.
To see what it sounds like before spending a bunch of effort you can pull the actuator cable off from the cam and hold it open with a small vise grip, or I got mine to reach up to the mount screw.
I reprogrammed the ECM timing for when my exhaust valve opens and closes. Not hard to do. I did mine very similar to Growls, but mine closes at 3500RPM:
"With the help of the module the exhaust valve can be switched to "always open" mode by means of a small switch. The sound of the XB12 models can thus be improved clearly audible. In the sound mode, the signals are simulated by the ECM and control motor, so that no error is detected by ECM. It may at any time - even while driving - switch in the series mode. The two modes are separated by the electronics electrically safe from each other. Supplied with matching for series wiring harness connectors, a mini-switch and ring cable lugs for the ground connection. The installation can be done in about 10 minutes. A rear armor anytime soon possible. The module is not licensed for use on public roads! Execution for model 2010 in preparation!"
It was a neat novelty trick. I removed it after a while. Not something you want to ride with while it is forcing the valve, you loose power. I get it though, and it is winter. Thanks froggy.
Thanks for the responses everybody. From what I can hear on the video, there doesn't appear to be much difference. Not sure it'd be worth it. But is there really that much power loss at lower rpm if it's left open? Based on the myriad of other non valved aftermarket pipes available and in common use, it just doesn't seem that critical in practical terms. If not using a valve really resulted in a gutless bottom end why would so many people install unvalved aftermarket pipes? I seriously doubt they really boost higher end without other mods in place to exploit any possible improvement.
But is there really that much power loss at lower rpm if it's left open? Based on the myriad of other non valved aftermarket pipes available and in common use, it just doesn't seem that critical in practical terms.
I'll explain this in practical terms. I was messing around in my neighborhood on the uly with the valve forced open. Lots of cars parked on the street and a car coming towards me. No problem, I pull out around the parked cage into the path of the moving cage and the engine falls flat on it's face. I'm very thankful for the grace the car driver afforded me.