I have put the standard exhaust back on and hooked up the EGCA servo and exhaust valve again per the service manual. Got me wondering what the normal operational parameters are for this. When setting up the cable tension again using the SCS jumper plug, the servo turns the valve all the way open, to where the marks on the valve on the exhaust itself line up. However when just normally turning on the bike without the SCS, the servo appears to turn the valve only slightly open from fully closed before then closing fully again once the bike has started. So my thinking is that there may be some variation in how open the valve is depending on the situation, rather than it just being a binary open or closed state? Anyone know?
The opening depends on the amount of throttle amount (exhaust gazes released) at certain RPMs. You will see it open gradually when gradually opening the throttle. This both reduces the noise level and increases throttle smoothness in lower RPMs. Removing the servo and keeping the flapper open will do exactly the opposite.
On my 2015 model it was related to speed to, the exhaust valve would open at 50 mph. So if you just reved it whilst parked the valve never opened, it needed to be moving.
Speed, throttle and gazes released are all one thing. As I mentioned before, the valve is there to reduce exhaust noise levels in low RPMs, i.e., city/street riding. If you give the throttle a good twist and the bike flies, then there is no issue with it. As long as the servo opens the valve to full open when shortening the SCS, then the ECU/servo are in perfect match and operational. Also, short the SCS circuit each time you adjust the tensioner, you will notice the valve indicator change position after adjusting the tensioner. I had to adjust few times until I got the pointer at fully open, adjust-shorten-adjust-shorten and so on. Mine is a 2018 model and I had to put the valve cables back on too after started getting complains from my coworkers and neighbors each time I start the engine in a closed space, also due the sluggish throttle response at low RPMs.
I thought it was 40 mph it used to operate at (but I could be wrong) and felt like it was always flicking open/closed when out. I was sick of that constant changing and hence getting/fitting the servo eliminator and leaving it open all the time. Can’t say I noticed any issue of sluggishness at low rpm, but happier the noise is consistent (and it isn’t much louder being a standard exhaust anyway, IMHO).
Sorry to dig up a relatively old thread (all very young threads compared to how old I'm feeling these days), but I'm wondering how one can tell what the "normal" settings/operation of the EGCA is in terms of position of the flap. The cables can be adjusted, but is it simply to make sure there isn't any slack? The workshop manual isn't helpful other than to outline the removal/installation steps. Just trying to think of all potential options for why I can't get rid of my DTC 35 error code for more than a few seconds after a reset. (I've posted in the General Discussion section). I suspect my problem is another electrical gremlin although at this rate I'll have had the same bike from new, but with nearly new everything - a bit like Trigger's ever lasting broom..
