| Author | Message | ||
     Conchop |
I've had vibration issues from the git - go between 2500 and 3000 rpm. I finally have them down to where my hands no longer go numb. So much more happy. But they are still there. Just not as raucous as they were. Things I've noticed. The fan rarely runs at all during normal operation [ EVEN LESS WITH THE IRRIDIUM PLUGS ]. Once the bike is hot it vibrates and once it is shut off and the fan cycles, it doesn't vibrate when you re-start and ride for a little bit. This makes me think I need some more fan time especially during normal operation. Is this fan computer controlled? Is it controlled by a thermostat? How do I change it to get more fan time? Any ideas? Thanks... | ||
| Conchop |
PS - this is an 08 so it is different and much faster than 06 and 07's LOL | ||
| Hughlysses |
The simplest solution to vibes between 2500 and 3000 RPM is to keep the bike wound above 3000 RPM. Patient- "Doctor, it hurts when I do this." Doctor- "Well, Don't DO that!"  Seriously, the isolators are tuned to eliminate vibrations at higher RPM's and the engine is happier too. If your vibration is really that temperature-related, it would seem to have to be a bad isolator or a mis-adjusted primary chain. The hardness of the isolators could be expected to change somewhat with temperature (hotter=softer); maybe one has a tear or something that is only detectable when the bike is hot. The primary chain gets tighter when the engine gets hotter. Of course, if it's getting tight enough to cause vibration, you should have difficulty in shifting too. The fan is controlled by the ECM based on input from a temperature sensor on the rear head. What you're saying about your fan operation seems consistent with what other 08 Uly riders have reported. The fan runs as much as it needs to- don't worry about it. I don't believe running the fan more would have any effect on your vibration. | ||
| Bienhoabob |
(Message edited by bienhoabob on August 05, 2008) | ||
| Gotj |
Conchop, I have the same vibration issue that you describe. The heavy HVMP bar ends don't do much, if anything, for it. Much of the vibration is felt through the foot pegs anyway. I have ridden other Ulys and XBs that are quite smooth in that rpm range, 2500-3000, so it may have to do with the quality control practiced by Buell. Maybe if you got into some serious ECMSpy adjusting, you could get it to go away. I have no idea about the fan. | ||
| Johnnylunchbox |
I've been having the same issue. As the engine heats up it almost feels like I'm riding a single cylinder. The vibes get worse as the trip wears on. If I stop for fuel, and let the bike rest a few minutes, it's smooth again once I start up, then gets worse as it heats up. It is most noticeable in top gear on the highway. Even in the normally smooth zones above 3500 RPM I can feel the difference. BTW my fan runs ALL the time. My oil was low and it was suggested that an insufficient oil level would cause the engine to run a little hotter than normal. I have since topped off the oil, but haven't been able to test the bike yet. I am pretty perplexed by this whole thing. | ||
| Johnnylunchbox |
see http://www.badweatherbikers.com/buell/messages/142 838/383045.html?1217798139 | ||
| Conchop |
Oh I've got good at keeping her above 3k. Too bad, as there are tight places around here where she has to slow down. There is useful power down there and drivability is a key quality attribute. The oil is fresh and the primary chain is tightened to spec. BIG HELP THERE. Loose chains jiggle more. Improperly torqued plugs played a big factor too. It just seems logical that if the fan cycling at a pit stop will temporarily make the demons go away, more fan is better. It is also my understanding that the transfer of computer open loop to computer closed loop w/ O2 sensor occurs in that rpm range. Perhaps a little programming would help. Thanks again... | ||
| Chas1969 |
The fan is for cooling the engine (mostly the head of the engine) and controlled by the engine head temp. sensor on the rear cylinder. The only thing that not many people talk about is the fan is major outlet for hot air to leave the bike. So if you ride the bike hard even in 50 degree weather the fan will run which sounds crazy compared to cars that only run the fan when standing still in hot weather. So XB Buells are fan dependant for higher load cooling. I wounder if Buell had just a open area where the fan is, would the bike cool better? Chas FYI: Vibration: Mine vibs the same cool or hot. The only mod that helped with vibs is wiring the exhaust valve open  (Message edited by chas1969 on August 06, 2008) |
