| Author | Message | ||
     Forestgrump |
Am getting vibration that seems to come from engine. Can't feel anything that's loose. Anybody got any ideas what to check? 06 Buell Ulysses 34,000 miles. DAMM, I love this bike. | ||
| Etennuly |
Front engine isolator. Look up at the webbing. If it is cracked or the bolt is bottomed out on the rubber it is the likely culprit. | ||
| Ulyful |
+1 on the front engine isolator. Had to replace one on my Uly with only 3,000 miles on it. Here's what a good one is supposed to look like (pic of newly-installed isolator):  A bad one has the cylindrical portion of the cast isolator bracket resting solidly on the large-diameter flange isolator bolt (with the thin piece of rubber in between). This is due to the rubber webbing inside the isolator being cracked and no longer performing its intended function. The excessive vibration comes from the two hitting each other as the engine vibrates, and it's particularly noticeable in the 1,000 to 3,000 RPM range. | ||
| Hughlysses |
If front isolator is OK, check primary chain adjustment. A loose primary chain will result in vibration at ~3000-3500 RPM which is normally sort of a sweet spot where you don't feel any vibration. | ||
| Forestgrump |
Thanx, Guys. Isolator is fine. Primary chain is correctly adjusted. I guess, I'll just wait til something falls off when I'm in the middle of nowhere. | ||
| Etennuly |
Lube the heim joint motor mounts also. They can lock up from corrosion/lack of lube, and cause vibes like a solid motor mount. | ||
| Sir_wadsalot |
Heim joint motor mounts? Is that like an unobtanium muffler bearing? | ||
| Electraglider_1997 |
Wad, Our bikes have 3 heim jointed motor mounts. Front ,top, and rear. http://www.speedwaymotors.com/Shop/Suspension-Arms -Bushings-and-Accessories-Heim-Joints/12.html | ||
| New12r |
Check the front muffler strap and mounting bolt, whenever I have a weird vibe, its always there. | ||
| Andrejs2112 |
Is the seat plastic rubbing on the head? I had to cut some plastic out of my seat pan because of the vibration. | ||
| Cyclonedon |
How hard is it to change the front motor mount? Mine is shot! The rubber bushing is torn and the bike is riding on the bolt, metal to metal! | ||
| Cyclonedon |
How hard is it to change the front motor mount? Mine is shot! The rubber bushing is torn and the bike is riding on the bolt, metal to metal! | ||
| Tootal |
Three bolts. Put a jack under the muffler to hold the engine in position. Loosen the large mounting bolt. This may be rusted in position so you may need a good allen wrench and a pipe to break it loose. Once broke loose then remove the two smaller screws holding the bracket to the motor. Now finish unscrewing the large bolt. I believe the new one comes with a new large bolt, if not, clean the old one and use blue Loctite on the threads. Loosely install the large bolt and then install the two engine bolts. Torque the engine bolts, with blue Loctite, to 50 ft-lbs. Finish tightening the large bolt and torque it to 50 ft-lbs. also. The book says you may have to raise or lower the jack to help with installing the large bolt. | ||
| Cyclonedon |
Thanks Tootal! I have the service manual and I was just wondering if there anything more to doing it than what they said. The dealer wants an arm and a leg to do it so I'm going to try it myself. | ||
| Uly_man |
"The dealer wants an arm and a leg to do". Why as it is easy enough to do? More likely is that they are not interested in doing it is why. One hour at the most to do and more like 15 mins in a fully equipped workshop. | ||
| Forestgrump |
Lubed Heim joints and checked muffler straps and all mounts. Didn't find any thing out of spec. Still am getting vibration. Maybe I should check the muffler bearings and the cransanator valve? | ||
| Etennuly |
Maybe I should check the muffler bearings and the cransanator valve?  With the XB 12 you actually do have a muffler bearing! Do you have the comfort kit? On mine the rear pipe cover moved up letting it's bracket touch the bottom of the tank making a bad vibration. The other thing that comes to mind is are you down on power a bit? Fouled or partially fouled plug could come into play. Or.....are you trying to run this engine under load less than 2,500 RPM? | ||
| Natexlh1000 |
Take off the flyscreen and see if the horn is buzzing up against the plastic. Look for plastic sawdust powder. Sometimes it takes very little to change it from SUCKS to GONE. like bending the little bracket 15 degrees. | ||
| Buewulf |
Are we talking about the kind of vibration that you feel, or are we talking about something audible? | ||
| Hoover_uly |
What a coincidence, I went for a ride Sunday and the first thing I noticed once I settled in on the highway was a vibration about 3500 rpm. The engine is typically very smooth in this range. It is definitely engine related since it stops when I pull in the clutch to coast. It feels like the type of vibration I would get at around 2500 rpm - not so severe but similar and certainly different than before. Drop it down a gear and the vibration goes away. Front mount looks OK. I have a spare to try if necessary. Based on Hughlysses' post, I'm going to check the primary adjustment next. Based on the maintenance schedule, it is due anyway. Since "checking the deflection" is somewhat subjective, can someone provide a bit more detail? Light/moderate or heavy force applied to check deflection? Would prefer to work on a cold engine but seems like the manual provides a spec for hot or cold. Thanks in advance for any advice. | ||
| Natexlh1000 |
I usually adjust on the loose side when the bike is cold. The aluminum grows more than steel when hot so it will tighten up a bit when up and running. Too tight = ouch, my bearings Too loose = more vibes | ||
| Electraglider_1997 |
Hoover, Don't drive yourself paranoid over a perfect tightness for the primary chain. I just make sure that the primary isn't too tight just like Natexlh says. Do it hot and then you know that it won't get any tighter and then later recheck it cold too make sure it isn't way too loose. That method will ease your mind. It sure would have been nice had those Buell or Harley engineers had as much respect for these engines as the Harley engineers do for the big twins. I'm referring to the nice automatic tightening adjuster feature of the big twin primaries. | ||
| Electraglider_1997 |
Anybody ever heard of this auto tensioner? http://www.sohotbikes.com/hb125xl.html http://www.sohotbikes.com/Hydraulic%20Automatic%20 Primary%20Chain%20Tensioner%20for%20Sportsters.pdf | ||
| Hoover_uly |
Natexlh1000 Electraglider Thanks for the adjustment advice. Hope to adjust and road test this weekend. | ||
| Hoover_uly |
This morning I checked deflection and it seemed I had a total up and down of about 3/4 inch. Adjusted cold to about 1/2 total and went for a ride. Seems to me the vibration I had is gone or at least greatly reduced to an acceptable level. Checked again hot and it had snugged up a bit but still 1/4 to 3/8 with moderate pressure on the chain. Think I will leave it there and call it good. |
