Introduction and request for info
I do own a 2010 KTM RC8R (not a jap bike). Thats what brings me here. My bike is a 1200cc v twin. I am in completely uncharted territory as I've taken the bike farther than anyone else. Most recently cams valve springs and titanium retainers along with extreme head porting and a new piston taking compression to 15:1. After the recent mods the bike will only run on one cylinder at idle but clears up under full throttle. It uses a speed density injection system at low rpm and Alpha-n at high rpm. I think HD uses a very similar system.
I believe the problem I am having is due to the erratic manifold vacuum at low rpms with a big cam v twin.
Right now I have unplugged the map sensors causing the engine to run in Alpha-n and it will idle fine. My plan is to dyno tune the bike with PCV and just run it in Alpha-n.
I know big cams are pretty common on Harleys so I thought you may have ran into a similar issue with the speed density system at idle/low rpm. What do you guys do to solve it? Thanks guys- Gary
And a video with it running in Alpha-n it still needs to be tuned
http://youtu.be/m2REjq8T_g0
Last edited by 2004boss; Dec 26, 2015 at 10:10 PM. Reason: Fix link
Is there two distinct intake runners and two throttle bodies that simply share the same air box?
As far as I know, Harleys only run SD or AN. Not both at the same time like Yamaha.
I would enjoy helping you out but I need to get thru the KTM learning curve first.
Andy
I run map based correction and TPS based correction at the same time on my Yamaha FZ1 all the time.
see www.nbs-stl.com/tuning for more info.
Also see http://www.nbs-stl.com/tuning/BasicTuning101.pdf
Andy
I have the pc5 with auto tune but no data log. I was hoping a tuner on the dyno could get it right in "An" and I could use the auto tune for small corrections at idle and low rpm/cruising. I don't think the autotune reacts fast enough for full throttle high rpm corrections but that's where the alpha mapping should be spot on?
The bike has a very nice tuning program called Tune ECU built into the keihin ecu. I've used this for most of my diagnostics because it shows all the sensors and engine parameters. Problem is, Noone knows how to tune with it.
Am I correct in thinking that I could have the bike tuned for wide open performance in Alpha then use the auto tune for corrections below 35%throttle/idle/low rpm5500 and down?
Last edited by 2004boss; Dec 27, 2015 at 11:31 AM.
Trending Topics
I was looking at the ECU Tune software. Depending on what we learn with the PC5, we can move what we find with the PC over to the ECU, if you want.
The Best of Harley-Davidson for Lifelong Riders
http://www.nbs-stl.com/MLVDemo/930%2...20vs%20RPM.png
Andy
Before I pulled the engine apart I had the auto tune installed but I wasn't really using it. I was running a leaded 110. Would that kill those o2 sensors?






