vibration in front with bumps

[kicker42]

I have a 80 XS1100 that I had a new tire put on and the shop said that the bearings were fine and the bike rides great untill I hit a bump then I feel a light vibration in the front after a few seconds the vibration gos away untill I hit the next bump. Did the shop lie to me about the bearings. I bought the bike there it was on consingment for the owners friend and the front tire was compleatly dryrotted so I had it repalced I aslo got the price droped to help cover the cost of a new dunlop.

[TopCatGr58]

The vibrations are probably not from bearings. Several factors can cause this sensation. Overpressurizing the front tire to max inflation ratings makes the tire very hard, and so it will bounce over bumps instead of taking some of the bounce in the flexing of the tire/tread.

Also, did they do a front fork oil fluid change before selling the bike to you?? Old fluid, improperly balanced amount of fluid between either fork tube, as well as a higher viscosity fluid than desired(15wt vs. 10 or 5 wt) could make the front stiffer bouncing more. Also, check your preload settings, may be set stiff?

Could also be loose steering head bearings, you'll need to jack up the front of the bike/frame to elevate the front wheel off the ground a little, then grasp the front wheel and pull up at a 90 degree angle to the forks and see if you can feel a "jiggle" loose rocking type of movement in the steering head, if so, then you'll need to take the handlebars off, and retighten the two nuts that secure the lower triple tree/steering head to the frame/bearing fitting. Since you're there, might as well pull the steering head out and clean and regrease the bearings, both top and bottom before retightening!
T.C.

[prometheus578]

While you have the front end in the air checking for loose steering bearings like TopCat suggested, also check the general condition of the steering bearings. Slowly turn the bars back and forth from left to right. (Or right to left if you want to argue)
See if you can feel any stiffness when turning, or if it feels like it catchs a little. (like a ball bearing sliding nicely along it's race, till it hits a rut) These spots are usually when the bars are centered, but I've seen them to the sides, also. Twenty five year old grease tends to get hard and gummy after a while, not too good for lubing
If you find a spot where the steering seems to drag a little, before condemning the bearings, make sure that what you feel is not the tightening of a cable or the flexing of the wiring harness.

[superdave]

Also !

I had simmular noise and found thr left case saver/motor guard was contacting the # 1 header pipe at the lower (2nd bend) Also the upper case mount touching the motor. I think there is enough flex in the frame to get them clicking together. Cleaned my savers up with a dremel. It went away. Also found another noise and or clunk from the lack of rubber stopper for my center stand/ in the raised position. Just a couple of quick things for ya to check !

[kicker42]

Thanks I havent had a chance to ride it since the post bur all your sugestions sound good. I did buy a manual for the bike so that should help me also I spent last weekend working on a freinds bike triong to get the front axel shaft out without detroying it ( LOVE THAT IMPACT) tryed hours with wrenches and vice it took 5 MIn with my impact. Back to my problem I dont hear a sound I just feel a slight vibration when I his a bump then it slowly gos away like the tire is out of balence then it straitens it self out and I have had the bike doing 90 on the free way with noo tire vibration unless I hit a bump and from my end it feel like the frount tire thrue the handel bars but what do I know I have never had any problems like this so I dont know what to compare it to. ALSO I found a 6.75 replacment fuse panel from auto zone that fits the same location and you can get to all the conections and solder the wire befor you snap them in the four place Blade type fuse holder it is solid look. great and is cheep.

[DeanR]

Exactly what fuse panel was that from auto zone? Might be interested!

[TopCatGr58]

Dean,
Below is what he got. I've looked at that one, but it looked like it would sit up/out too tall/far from the base of the OEM block!? The one I got from Pep Boys a few years ago, they NO LONGER CARRY, it was flatter to ensure that it would fit inside the side cover!?
Hey Kicker, can you take some photos and show us how you fit it into your fuse block area!?
T.C.

Painless Performance 4 Circuit ATO Fuse Center

4-Circuit Fuse centerCompact and can be used on any vehicle where additional circuits are needed.
Ideal for in-line wiring applications, such as trailer wiring or when adding vehicle accessories.
Uses ATO blade type automotive fuses up to 30 amps.

Part No.: 30002
Weight: 0.175 LB
Price: $6.99

[schpiff]

vibration

Welcome aboard Kicker,

My 81 sh with about 16k on it does the same thing...I am convinced its the springs somehow harmonizing with the engine for a split second...only on short sharp little bumps.
I have been all thru my forks, wheel bearings, and steering head bearings.....never changed.
I just tell myself queitly enough so SWMBO dont hear, that if I have time to worry about that little bitty vibration, we aint goin fast enough!

I had to add...i didnt notice the buzzy vibration on little bumps till after i put a elite II tire on the front...kinda stiff sidewalls. But even running the tire on the low side of inflation it still does the same.

[kicker42]

fuse panel

Yep that is the one. I have one screw in a hole above the origonal hole and that is holding it secure it fits great and a lot better conection that the glass ones. if I need I can drill a hole and secuer the other hole. how do I add a pic