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tcat
05-13-2007, 04:11 AM
just picked up my new long lightning. I've put 300 miles on it and it runs great at 3000 rpm and above. Around town at 200-2800 rpm it surges and just doesn't seem smooth. Took it back to the dealership and they said its fine. Is it the nature of the beast or is something wrong?

2Evil4U
05-13-2007, 02:54 PM
Is it brand new? If so it's pretty normal. The bikes don't like running smoothly below 2k at all. As it breaks in it will get a bit better, but it's difficult to not jerk it around at low RPM and slow speeds. Best bet is to keep the RPM at 2200+. Also, if it is new, when you get to the 1k TPS reset it should help as well.

BlackBuelly07
02-13-2008, 11:30 PM
I am having the exact same problem at 2600 miles. Has it ever backfired through the airbox?

BuellPartsGuy
02-14-2008, 02:38 AM
tcat, the bike isnt intended to operate at that low of RPM's. Thats why its so rough.

Big Jon
03-14-2008, 07:20 PM
My 07 Long did the exact same thing straight out the box. Have around 6000k on it now and it has smoothed out considerably. BPK is right, if you operate the bike above 2800 rpm it runs smoother and has better fuel economy. I run 4th gear between 3k and 32 k and it is real responsive.[up][cool]

The Kelzer
05-23-2008, 06:51 AM
Yep...same here. Surges down low.
TK

2StangBK
09-05-2008, 02:09 AM
I've heard it called "lugging". Or at least thats what they advised me not to do when I broke in my Nighttrain several years ago. Low rpm's it will do the surging especially on a newer engine. For the elder Buell riders is there a consensus about crusiing RPM's? I just picked up my 04' XB12S about a month ago.

gbalias
09-17-2008, 01:33 AM
it is known that the mapping is less than optimal for those ranges in the RPM/TPS that youre speaking of. some tuning of the ECM will make it run smooth.

mine runs perfect all the way from about 12-1300RPM to redline. no surges, blips, hesitations, etc. i was disappointed when the dealer told me this was "normal" too. i only had about 600mi on mine before i fixed it. i should go work for the dealer. pffft!

skellybuell
09-17-2008, 06:18 AM
maybe check tension on primary..

ridendude
11-20-2008, 09:46 PM
I agree with skelly, check your primary. If it's slack, it'll be really nasty to ride below 3K. Adjusting the primary makes a huge difference to rideability at parking lot speed. Try the breather reroute as well. Big improvement to quality of ride as well.