With regards to an EFI like the EHS bullet box, I'm indifferent on mine. It is one of the reasons I asked about elevation. Yes pretty much all ATV brands produced in the last 5 years or so seem to be reported as running lean in North America because of EPS regulations. That is why many have turned to adding fuel injection tuners. Seems that issue is worse at below 1000' elevation. EHS does his evaluation at probably 200' elevation.
What I've come to find out about the bullet boxes is they are good for being able to adjust fueling but they only add fuel, you can't subtract fueling. When you're running lean that is really all that is important. Add in elevation and now the equation changes as those at elevation are not getting the same O2 levels into the combustion chamber as one would get near sea level.
Yes, I'm currently running an EHS bullet box tuner. No, I did not leave the settings as was recommended by EHS and in many cases, I had to reduce the added fuel the EHS tuner was adding. How do I know? I also have installed a Koso wideband AFR meter to where I can realtime monitor the air/fuel burn ratio on my specific Grizzly at my altitude while under load. I actually turned off additional fueling for low throttle. Mid-throttle is where I'm adding a little bit of extra fuel. High throttle has very minimal added fuel. What I really would like is the ability to add or subtract to OEM fueling and this is not an option with bullet box style fuel injection tuners. I would need to go to something else like a Power Commander V.
Thanks Rocket!
Yeah, this whole EFI/fuel management, aftermarket tuner topic, has me a bit perplexed. As I've noted in earlier postings, I have some limited experience with them, by way of tuners for Harley-Davidson (HD). I bought a new HD in 2017, and unlike this Kodiak, I simply did not have the luxury of waiting out the factory warranty to install one. The HD simply would NOT run without it. It ran SO lean, and SO hot, that it was literally dangerous. Temperatures fully capable of warping sensitive aluminum engine components. So I threw a decent tuner on it in a matter of days after purchase.
But this Kodiak is an altogether different matter. Yes, it's plenty lean! In fact, ridiculously so! And like the HD, I'd love to throw a tuner on it now, or in the near future. But factory warranty issues aside, the EHS tuner does not compare to the sophistication of the HD tuner, which used active O2 sensors in the twin (nearly wide open) exhaust pipes, to constantly fine tune fuel, air, timing, etc., every time it was driven, using an "auto-tune" program, that could then be flashed to the bike, at any time during the process, when (and if) desired. The EHS tuner does not offer anything like that level of refinement. As best I can tell, it's far more 'manually' programmed, and without the active O2 sensors, or a sniffer, or the other necessary monitoring devices, I just don't see how a guy could get a fully optimized system (fuel/air/ignition timing, etc.), in his home garage. Add the elevation differences (as you've pointed out), and you're left flying by the seat of your parts, or more accurately, you're left "fine tuning" things, almost solely by ear.
And, like you've said, the alternative is to go with a tuner that is more comprehensive, more like the one I used on my HD, something like the Dyno-Jet Power Commander V, which apparently lacks the direct WiFi connection to a smartphone like my HD tuner has, but can still be connected to a laptop via USB.
The downside is, you cannot connect the Power Commander V wirelessly to ANY Android or iOS mobile device (smartphone or tablet), nor can you connect it via hardwired (USB) connection to anything but Windows/PC computers or laptops (no Apple or Mac devices). And since I wouldn't own a PC, that's the end of the road. Sorry DynoJet!
