I installed an S&S124 in my 06 Ultra last year and have notice an excessive amount of engine braking when I let off the throttle. I talked to some guy's, that were thinking my Calibration might be shutting off the injectors at closed throttle, causing this excessive engine braking, is that possible? I am using FNM-141 is that a cal that would shut off the injectors and if so, what cal should I use, that wouldn't shut them off?

 

Shutting off the injectors will not cause engine breaking to be dramatic. Maybe a little bit but by no means like a sumping engine, which feels like you’re dragging the rear brake while riding the bike and when you let off the engine breaking will be dramatic,
indications of sumping is lack of “snap” to the power. Quick build of heat and gets hotter than normal while riding.
Not saying your new engine is sumping but it IS possible... so draining the sump to see how much oil is left will give a window into the scavenge side of the pump which is supposed to remove most all the oil from the bottom of the engine and return it to the tank. A couple ozs is ok but when the amount gets above 3-4ozs sumping is occurring.
Bob

 

I will check for sumping, but I haven't noticed any lack of power or heat issue. But one thing is that I'm getting a lot of creamy oil in my catch can, its like pudding its so thick.
The other thing I notice is when I let off coming to a turn and then open the throttle again, it sounds and feels like the engine is refiring, like something shut the kill switch off and then turned it on again.

 

The grey poupon in the catch is standard for a big motor, especially when the humidity is up or you have a bit more cylinder leakage. Your hesitation after roll off, IMO, it likely tune but you should check fuel pressure.

 

Think some Cal's do shut them off, bigger engine would probably make it more noticeable perhaps? I'm using an SE 120 cal in my 110 and it does it, it's noticeable but not bad, more annoying than anything, PM Steve Cole, he might have an answer on an alternative calibration if that is the cause.

 

Ok I think I ruled out the sumping, I checked it today and acordiing to S&S 8 to 10oz would be normal on the twin cam S&S124
So that looks good, so something else must be causing the engine braking.

 

Played around with my closed throttle spark today. I lowered the numbers closer to whats in my timing tables and seem to have smoothed the transition between closed throttle and just coming on again, maybe reduced some engine braking too. Think I will put the original back in again and see what it was like again.Most of my low rpm timing is set at 17 does that sound about right for a 124?