Originally Posted by Rubberbband
2010 f650gs now stutters when I snap the throttle wide open when the bike is cold. Bike acts great when warmed up but I am wondering if anyone else experiences this? It's almost like I have a choke installed now...my dirt bikes bog when choked but run great warmed up.
(Disclaimer: I have three BoosterPlugs)
I haven't read many reports of that happening but I noticed the other day that my R1150 starts just a bit better without the BoosterPlug attached. Since I'm always monitoring the mixture with my LC-1 I know that the reason is NOT that the BP made the mixture too rich. It was essentially the same, indicating that at cold start the oil temp is the main determinant for fueling.
Here's something to think about. Without a BP, if you let your bike sit overnight, the air temp equals the oil temp. It is possible that the BMSK recognizes this air=oil temp condition and uses it in its cold-start algorithm.
When you put a BP in, say the garage temperature was 5 degrees C. The oil temp after a night or sitting would be read as 5C but the air temp would be read as -15C. Maybe the BMSK sees this as a different starting situation.
I'm just suggesting a possibility. I think most likely if you ride with the BP for a few tanks of fuel,the BMSK will learn around it and the condition you reported will improve.