Okay, going back a few years so far as twin cams go. I purchased an 06 Road King Classic (fuel injected) and it has 8-degree injectors. They had an issue with them and many were replaced by H-D to the newer (CVO-style) 25-degree injectors. I've read many times how swapping the injectors corrected the issue. I'm not sure if my issue is in fact, the 8-degree injector issue.

My bike runs great, except for one spot. At VERY low throttle and around 2,000 rpm, my bike sputters and jumps. If I give it a little more throttle, it goes away. If I give it just the slightest amount of throttle, it sputters again. Sometimes, it can make you look like you don't know what you're doing!
Before you all start saying "use your clutch!" it's not a clutch issue. It literally "hunts" and sputters at around 2,000 rpm and low throttle. I'm wondering if this is what the 8-degree injectors acted like. I've always heard it was a cold-start issue.

Anyone here remembers the 8-degree injector issue firsthand and care to share your thoughts or what prompted you to have them swapped out? I don't want to go swapping parts if that isn't the issue. Other than that little spot, the bike runs great!

Thanks for any insights.

 

The injectors may be part of your problem, but not all of it. I'd swap them out as you might be able to get a little better mileage. Let the Tmax adjust and see if it goes away. If not I'd change the injector timing to a number closer to 360 and see if that helps. If not play with the partial throttle timing and AFR mixture at 2048 rpm and 2304, I'd advance it a little and see how it runs.

You could simply change the injector timing and that may take care of the stutter. You will need the advanced user license to make the adjustment. IIRC there are steps on how to do this on the Tmax website. It requires an email requesting the license. The adjustment is in the module configuration / Basic setting window.

 

Thanks @Max Headflow!

I've been trying to work out the stutter several different ways. I've tried to keep the timing maps pretty similar in that area to help keep from "cross-talk" between maps. I've been bumping timing and working with the AFR to help with fuel mileage as well. Best I've gotten so far is 37 mpg but the bike has REALLY responded to an increase in ignition timing. I do have the advanced user license and did bump the injector timing a little bit (Not all the way to 360 though) from the original 392 degrees. I figured with the Andrews' earlier intake valve closing event (32 degrees), it couldn't hurt. I tried to do the math once of how far to advance it from the original cam's timing but my head started to hurt. LoL. I'll bump it a little more and see how it does.

Also wondered if the 25-degree injectors' additional spray ports might help atomization and fuel mileage as well. Good info!

thanks!

 

Set it all the way to 360, I bet it helps..

From what I gather from TH, it's the time after TDC on the compression / power stroke when the injector spry stops. 360 puts it right at TDC on the exhaust / overlap. It sounds strange but the motors seem to like some spray on the closed intake valve to get a better burn. When you got to bigger injectors it's a must (you don't need to).