Several issues in the past few posts...
First, you can't upgrade a SEPST to TTS. It's the old SERT which you can upgrade. TTS made the SERT and it's basically the same hardware. SEPST is made by a different company and the hardware is different. If you were a hardware/software hacker you could probably get any of them to use any software/calibrations you wanted, but not only would it not be worth the time and effort, it might net you some "time" as well.
The V&H pipes, from what I've gathered from forum posts here and there, often have sensor bungs which are both less than optimum in configuration as well as in placement. If the sensor isn't well into and sufficiently bathed by a good stream of exhaust gas at all times it cannot produce good information for the ECM at all times. It's entirely possible your low-engine-speed dissatisfaction results from that situation, compounded by reversions brought on by the overall configuration and by your cam selection. In such cases, if "fixing" the sensor bungs doesn't solve the problem you'd probably just have to forego closed-loop operation in that area, and that's really not a major issue in and of itself. Pretty easy to do with the tuning equipment you have. But it wouldn't be
my first choice; I'd try to fix the cause first.
Perhaps a better description of "throttle lag" is in order? Is it that the engine stumbles or is it that the engine doesn't make as much of its power as you'd expect for the amount of twistgrip movement?
I've found a thread here in which it's mentioned that the throttle blade control table in the SEPST does not "work" in either 1st or 6th gears:
http://www.cvoharley.com/smf/index.php?topic=69358.msg962423#msg962423I'd assume your predicament is primarily of concern while in first gear? If so, and if the above information is correct (I don't doubt it based upon who said it) then you'll likely get no joy making that adjustment anyway. An alternative would be to adjust the Acceleration Enrichment in just that area. Without having that software at hand I can't say just how easy that would be to do. My gut tells me that an adjustment to just that one area would not "harm" an otherwise good tune in any way, and if the H-D software is even halfway good it shouldn't be too difficult. In any event, you can try either or both adjustments and if it doesn't do what you want, simply revert your changes.
I find the throttle blade control to be a good thing. I've attached the table I have in use on my bike. I don't recall changing it from the base TTS calibration I used. You'll see that once the RPM reaches 2500 the throttle blade follows the twistgrip from then on out (the bottom row values extend to all the higher RPM). At 1000 RPM the most the throttle will ever open is 17%, no matter how far I twist the grip. It gets progressively more 1:1 as the engine speed increases.
I like it very much. There's absolutely no delay. Whenever I twist the grip the engine speeds up. It just does so at a non-linear rate. When I'm in a low gear with the engine speed down just plodding along the throttle isn't so sensitive to my input and I find it much easier to control smoothly.
The calibration Fullsac sent me (which I didn't use) had all the column values maxed out to match the column headers. I cannot understand why anyone would want to do that unless the cam they were using was particularly "soft on the bottom". I like the SE255 which is just about "on the cam" at idle; it suits my riding style much better than what most folks are posting here for their dyno charts.
You'll note my 20% column is already 1:1 just off idle. How many of you ever open your throttle even that much just off idle?
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Topic: Hesitation in throttle response off idle? (Read 24747 times)