every now and then when i shift from 2nd to 1st, i get a very high idle, like i'm opening throttle or it's stuck. doesn't do it often but often enough i'm wondering what the problem is. i have a 2008 sportster 1200L 105th anniversary edition. any suggestions?

 

I dont think thats consider an idle when your shifting from 2nd to 1st. Or am I not understanding this properly? How fast are you going when you do this?

 

I have a similar problem sometimes when I run the twisties and use a lower gear and higher RPM to utilize engine brake. My symptom is that when the bike comes to the complete stop, the idle RPM is higher than normal and it takes 3 - 5 seconds for it to come back down to normal idle RPM. This also triggers the DTC P0505 (check engine light code), which is a loss of idle speed control.

The P0505 code is triggered if the RPM is + or - 200 rpm the normal idle rpm for more than 3 seconds when the bike is completely stopped.
I did some research and some people say that taking off the air cleaner and cleaning out the pintle hole resolved the problem. I gave it a try and afterwards noticed that the bike feels like it runs better but I still get that code triggered although I've noticed that the time it takes to return to normal idle rpm is much faster...but still long enough to trigger the code.

The way I see it, it only happens for me when I run the twisties and I don't think it's a huge problem so instead of taking it to the stealership, I think I'm just going to continue resetting the code. Some guy took it to his dealership and they installed some new component that cost him $500...not worth it in my opinion.

 

thanks for your quick replies. it seems to do it when i'm coming to a red light or stop sign, downshifting from 2nd to 1st.