| Author | Message | ||
     Swordsman |
I just got my bike back from having a new rear tire installed on Saturday. It was behaving normally on the ride home. I decided I wanted the airbox back to stock, so when I got it home, I duct taped over the left side holes that I added way back when. I didn't take it out for a run afterward, assuming everything was fine. Well, I brought the bike to work this morning, and it's acting weird! I noticed at my first stop sign that the RPMs are really slow to come back down now. And rather than leveling out at 1100 like it used to, it hangs up completely at 1500 RPMs. If I just let it sit like that, after another minute or so (literally, like 60-90 seconds), it will finally idle back down to 1100. It's still doing this after a 30 mile commute. If it was a simple matter of the ECM "re-learning", I would have expected it to work itself out in that length of time. Surely putting the airbox holes back to stock couldn't be the cause of this...? I'm not running any custom tune or anything. Does anyone have a clue what could suddenly cause this? Thanks, ~SM | ||
| Staffn |
TPS Reset or just adjust the idle via idle screw beside L/S scoop | ||
| Randomchaos |
Did you happen to pinch off the gas tank vent hose when you put the airbox cover back on? Not sure if that would cause this issue, but worth checking. | ||
| Mnbueller |
AFV. Your bike most likely "learned" from the open air box and the adjustments it has made are causing your issues. Rest the AFV and since you're in there, might as well reset the TPS (just for good measure). | ||
| Swordsman |
The TPS was reset just a few weeks before it went into the shop. Not to mention, the TPS wouldn't go nuts from one ride to the next. Same goes for the idle adjustment. Wouldn't a 30 mile ride be enough for the AFV to adjust itself back out if it were the culprit? I mean, honestly, what's the point of even having it if it takes days of riding to do anything? ~SM (Message edited by Swordsman on June 25, 2008) | ||
| Mnbueller |
Yes I see your point... Other possibilities: vacuum leak (intake seals..) could be that throttle is sticking open. check throttle cable adjustments. I only say to rest the TPS and AFV because I have ECM spy and its like a 3 min fix. My bike, out of the blue one day, just started to want to die when it was at idle. Ran perfectly fine the day before. I reset the TPS and AFV and its ran great ever since. As odd as it is, the TPS and AFV reset tends to be the cure all for these bikes...probably has something to do with cheep made in china sensors that drift...but who knows. | ||
| Swordsman |
Hmm. If it's still doing this after I get home, I'll strip the tape off first and see if that changes things back to normal. That'll at least let me know if it's something deeper. Either way I guess, I can do the resets and see if it helps. ~SM | ||
| Buplaux |
IMO it is the afv. I messed around and richened up the closed throttle portion a little to the right(higher) of idle rpm and it caused it to hang. I am almost positive your ecm corrected the fuel map richer for the increased airflow and now it is too rich causing it to hang. It should relearn but it may take some long highway rides. I sometimes have to ride 50 or 60 miles of constant highway steady rpm to make mine correct the afv. Jeff | ||
| Wantxbr |
Did you try and take the tape off the air box and run it again to see if it ran normal again? | ||
| Ferocity02 |
Mine did the same thing. It only does it when warm though. I did the TPS reset and lowered the idle a smidge and it worked. | ||
| Buell_41 |
head temp sensor... fixed my hanging idle problem... $50 from American Sportbike. | ||
| Swordsman |
Well, I got home and immediately hooked up ECMSpy. My AFV was sitting at 110.8, which is the highest I've seen it. So I reset it to 100, and reset the TPS, and adjusted the idle out to about 7.5%, which puts my idle right around 1100. I didn't get a chance to take it for a run afterward, but I'll use it to go to work again in the morning and see if it has straightened out. BTW, I did NOT take the tape off. I want to see if these changes have any effect without making any other adjustments. ~SM (Message edited by Swordsman on June 25, 2008) | ||
| Etennuly |
It is quite simple really. I had the same issue a long time ago. Set the idle down about 25 to 50 RPMs. 1100 is just high enough to enact the ECM to change timing and mixture. Makes idle go stupid fast and kinda float back to about 1500. When you put the tape back on the holes it is likely it raised the idle a couple RPMs, just enough to push it over the edge. Idle may have been adjusted when the engine wasn't warmed up all of the way. Mine idles best when completely warmed up at about 1000. There will be many threads about this in the knowledge vault. When they were new we all went a little nuts figuring this out. Your idle should be at 1050 anyway. | ||
| Swordsman |
Ah, I was thinking the idle was supposed to be at 1100, but I was just going from memory. I'll get it warmed up good and scale it back a bit then, and see how that works out. Thanks for all the info guys! ~SM | ||
| Swordsman |
Okay! Well, I fired it up and let it get good and warm, and it seemed like the TPS and AFV reset did the trick. I'm not exactly sure why, but the main thing is that it DID work. To be on the safe side, I went ahead and scaled my idle back just a hair... it now idles right at or just a tad below 1000 rpms. I took it out for a spin to make sure it worked out on the street as well as in my garage, and lo and behold, everything's back to normal. Thanks for all the input! Now I can datalog this thing and be confident about my results!  ~SM | ||
| Etennuly |
Excellent! Ride that thing!  |
