| Author | Message | ||
     Hughlysses |
I had to learn this a couple of times on my tuber and now I'm learning again on my Uly: proper primary chain adjustment makes a huge difference in the vibration level on these bikes. Back this summer, I did the 10k service and the adjustment was right on the money at that time. Shortly afterwards, I went on vacation to the mountains in north-east Georgia. One day I did a LONG (~30 mile) ride on gravel forest service roads north/west of Blue Ridge through the Cohutta Wilderness. See link for route: http://www.blueridgemountains.com/driving_tours/Co hutta%20Driving%20Tour%202.pdf I spent ~90% of the ride putting along in first gear on very deep gravel with some pretty rough sections. Later, I noticed the bike seemed to be vibrating more than usual but it was a subtle thing and only evident at certain RPM's. You know how the vibrations normally disappear at ~3000 RPM? Well, my bike would get "buzzy" above this RPM and would seem to be worst at 3500-4000. Vibrations were also very evident in the footpegs, something I'd never noticed before. After vacation, I did some checking and found what appeared to be the beginnings of cracks in the front isolator (several threads on this subject here), so I took it to the dealer. They checked it out and didn't find anything. About a month later the bike was still bugging me so I checked some threads here and found reference to broken muffler straps causing vibes. I checked those and they were fine. I finally decided to replace the front isolator on my own and noted some improvement, but that may have been psychological. I rode the bike to Buelltoberfest (~1000 mile round trip) two-up and things didn't seem too bad but the bike never seemed as vibration-free as when it was new. Yesterday, I took a fairly leisurely ~100 mile ride and by the time I got back, I was convinced the vibrations I was feeling HAD to be abnormal. The only thing I hadn't checked recently was the primary adjustment, so I as soon as I pulled in the driveway, I got the tools out and checked it. Sure enough, the chain was loose (probably about 5/8" play hot). It took about 15 minutes to adjust it to spec (1/4" to 3/8" play hot) and check it in several spots (put tranny in 5th, turn engine using back wheel). A quick ride and I have a like-new Uly again. My theory is the extended low speed chugging I did on rough gravel probably caused a lot of jerking with the primary chain, which either stretched the chain a little or wore the adjustment shoe. Anyway, if your XB's vibrating, don't forget to check the primary chain. | ||
| Geopatr |
Good to know. I'll be doing the XB9 primary conversion soon. I'll have to pay close attention to the chain adjustment. | ||
| Greenman44 |
I have tried to do the check and adjustment on my 06 Uly. Were you able to do it with the plugs installed or not. I wasn't able to get a measurement every inch or so while rolling it forward? Thanks | ||
| Ironhead1977 |
Thanks for the heads up.I have developed the same vibrations you describe and will be checking the chain. | ||
| Bertotti |
I can't imagine needing to pull the plugs for a primary chain adjustment!  | ||
| Johnnylunchbox |
I was just complaining that my Uly was exhibiting harsh vibrations in what should have been "sweet spots". I will check the primary. I have made the connection before on my 12R, but for some reason I didn't think of it on my Uly. | ||
| Hughlysses |
You can definitely do it without removing the plugs, but it does take some effort. Like I said, put the bike in fifth gear, which gives you maximum leverage to turn the engine. You have to apply steady force to get it past TDC on the compression strokes but it will go. | ||
| Rwven |
What do you use for a gauge to measure the free play? Is there a visual trick such as a point in the inspection opening to use as a reference? | ||
| Hughlysses |
I have a steel scale that happens to be 1/2" wide that I use for checking the cold adjustment. I can hold it against the primary case beside the chain and compare the chain movement to the width of the scale easily. I rummaged around and found a zip tie that had a 5/16" wide end, which was just right (1/4" to 3/8") for the hot adjustment. Note that you have to push the chain down and up to determine the full movement. | ||
| Atoms |
uh, how do you turn the engine? Push the bike? or turn the back wheel with the bike up on a stand? thanks! | ||
| Hughlysses |
Either will work. I turn the rear wheel by hand with the bike on a bike jack with a wooden muffler adapter. Be sure and put it in 5th gear because you won't be able to budge it in anything lower. | ||
| Atoms |
Thanks Hugh. I don't really miss doing valve adjustments on my airhead, but I do miss having a center stand at times like this. | ||
| Froggy |
Atoms, whats worse is my Micron can't be used as a jacking point like my old Drummer, can't get away with using the scissor jack I got laying here  | ||
| Conchop |
BINGO!!! i have the worst lawnmower vibrations ever on my Uly. 2500 to 3000 rpm is a bad place to be. Tried many old school tricks. Its the primary chain causing the bulk of the vibes. I have found the tighter 1/4" adjustment to be helpful. Shifts easier too. We should not need to be having this discussion. | ||
| Electraglider_1997 |
Buell needs to provide a auto-tensioner that we can install. Harley big twins use them as standard equipment. And sell them for older models for 100 bucks. | ||
| Hughlysses |
Somebody used to make an aftermarket auto tensioner for Sportsters and Buells but from all reports it was total junk. I do wish the factory would develop a good auto tensioner. That would make these bikes almost completely maintenance-free apart from plugs, filters, fluids, and tires. | ||
| Moosestang |
Does anyone have a pic of what the front isolator is supposed to look like? After looking with a flash light, mine may need replacing. Do you need to support the engine to change it? thanks guys. and girls, if any.  disregard, wrong post. (Message edited by moosestang on October 21, 2008) | ||
| Greenman44 |
I had a question about a Uly's chain tightness. I did the adjustment and on the first measurement there was roughly 7/8-1" of play. I set it to about 5/8" and wanted to make sure that this wasn't to tight. All measurements were cold. I'm a little paranoid and don't want to over tighten and create a problem. I have a 2700 mile trip next month and don't want to only make it part of the way. Thanks guys for the help. Greenman  | ||
| Hughlysses |
7/8-1" is WAY too loose. That's probably enough slack for the chain to be flopping around in there contacting parts of the primary. You are right to err on the side of loose. If you take your time and measure the chain free play in several places you will be fine. 5/8" is a little loose if anything; spec is 3/8" to 1/2" cold IIRC. Just make sure you measured the complete freeplay. You have to push down on the chain, start your measurement, then push up on the chain and complete the measurement. The chain will generally move just a little in the downward direction but much more in the upward direction. | ||
| Greenman44 |
Hughlysses, Thanks I did measure the downward and the upward movement. For sure there was a lot of play, I just wanted to make sure I wasn't getting carried away with the adjustment. Thanks for putting my mind at ease, I will check it again and adjust to your specs. Thanks Greenman  | ||
| Hdbobwithabuell |
Most useful thread yet. After reading, I KNOW my primary is to loose. Cant wait to get rid of those new vibrations that I've been unable to figure out. | ||
| Greenman44 |
I know when I came across this thread I knew it also. I had a vibration emerge about 3500 and new it wasn't normal. I just don't know if I tightened it enough. It was so loose I was worried I was doing to much. I'm thinking I will check it again to verify its right. I really like this web site..Thanks for everyones help. Greenman | ||
| Bertotti |
Yep I'm sure mine is lose as well. I noticed a lot of extra vibes on my last ride and stop light sitting. Got the primary to do at some point and then will be a good time to fix it up proper. | ||
| Workinman |
This is perfect! I bet that's what I'm feeling. Is that what the black covers are for on the left side of the bike or do I need to remove the whole cover to adjust? Will I need a new gasket? | ||
| Froggy |
You just remove the smaller of the two black windows, the bigger one is for the clutch. I haven't needed to replace the gaskets yet, but I have one or two on the shelf just in case it leaks. | ||
| Workinman |
OK so I know I break the big nut loose underneath the primary cover to allow play in the adjuster. How do I reach the adjuster from inside the small black cover? I have a manual on order right now but I am dying to ride right now! I changed all the fluids over the weekend and neutral is a lot easer to find but it still vibrates like a mother when I move through that RPM range. | ||
| Bobbuell1961 |
the bottom of the bolt that the large nut is on accepts a 1/4" allen | ||
| Matchanu |
There is an allen wrench slot on the bottom of the bolt were you loosened the lock nut. Just turn it clockwise to tighten. It's super easy. | ||
| Etennuly |
The big nut is the lock nut. The screw sticking down it the adjuster screw. Loosen the lock nut, turn the screw in(clockwise) to tighten. It has an allen head on the bottom.  but almost everybody knows that! (Message edited by etennuly on January 11, 2010) | ||
| Hughlysses |
Wow- this thread got resurrected from the dead. Glad to see it's helping some people out. For those of you that haven't gotten your shop manuals yet, you can use the on-line manual for the S-1 because the procedure is the same: http://www.badweatherbikers.com/buell/Manuals/S1_1 996-1997_Service/intro.pdf Click on "maintenance" then "primary chain". The primary cover looks a little different, but the adjustment procedure is the same. Remember that slightly too loose is better than too tight on the chain adjustment. |
