So I recently put on a DK 587 A/C and V&H blackout 2 to 1. I am using a power vision with a fuel moto tune, and the auto tune pro. My bike seems to chug along when I am not accelerating, just when I am trying to maintain a speed. I think my tune is good, so what other things can cause this. My rpms aren't to low I think. There's no delay or lack of power when I accelerate. Also anyone who has used an auto tune of some kind, how long do you ride in a "tuning session" or whatever it would be called before applying the changes?

 

I think the tune is the problem.

 

Chugging, do you mean lurching, or like feeling the engine pulsing? Or is more like the throttle is changing even though you are keeping your throttle stationary?

If the first, that really sounds like lugging. I don't remember if you have 883 or 1200 gearing, so here are both charts. Sporty's like RPM's up around 2800 or higher.







If it is more like the throttle is "hunting" then could be an intake leak, or the tune is off.

 

more like the engine pulsing, but what do you mean by the throttle hunting?

 

I was reading somewhere that an improperly adjusted primary chain could cause surging, is there truth to this. I didnt pay any attention to adjusting it when I changed my clutch pack.

 

Sounds to me like you're "lugging" it. Stop it. Lugging your motor is very bad for the primary chain. It will cause it to stretch prematurely and cause you to have to replace the chain and sprockets early. Sportsters like RPM's.

 

non-technical answer: On EFI bikes the computer can get confused at cruising throttle and you will actually hear as it feeds more then less then more fuel through the injectors...even though you are not moving the throttle.

A primary chain that is too loose will also make the bike feel like it is surging at cruising (it won't do it on acceleration or decel).

 

Ya, I checked my chain and it is very loose.

 

Ok, new problem. I tightened the primary chain a bit, along with checking my throttle/idle and clutch cables and now the bike wont go above a certain point in the rpms until i really twist the throttle it will suddenly jump up with a loud pop kinda noise. HELP!

Quick thing, I was turned the engine over to check the primary chain slack. can you just start the engine after turning it a few times or do you have to turn it over completely or something?