Driver Seat high vibration question

[Old Geezer Richard]

  I just bought an Ultimate Bigboy seat and I been noticing a high pitched type of vibration right on my tail bone right about  :Dwhere the slit is for the backrest go's , when I run my Fat Lady thru the gears ..... I don't feel anything until I'm around the 4500 rpm range and higher ..... nothing if I'm driving normal in and around town 3000 - 3500 rpm's .... could it be there is a frame in the seat where the backrest slides in is loose ? the seat is sitting flush and no breaks or cracks in the pan , so what could it be ?  or could there be something else in the bike that could be loose to cause that vibration ?

[Black Dog]

May be a silly question, but have you done the same 'through the gears', and RPM range, with your old seat on the bike?  Good place to start, would be to be sure it's the seat, and not the bike...  Didn't you just rebuild after a crash?

Black Dog

[hubcapsc]

I got some squeaks out of my Ultimate seat because it has a metal base instead of a plastic base like the OEM seat.

I put plasticoat on the tab and slot and killed most of the squeak... perhaps the metal base has something to do with
your vibration?

-Mike

[franco6]

OLD GEEZER vibrations at high speed sound like a u-joint .ask dave

[RainMaker]

I'm thinking the same as franco - my ultimate seat did not cause any difference in vibration, so I'd be looking at some other reason for vibration such as the drive train.  If you switch seats back and the vibration is the same, then you'll know for sure.

RainMaker

[asfltdncr]

Valks aren't supposed to vibrate.

[Disco]

Geez,

The vibration I noticed before my u-joint failure were mostly in the handlebars.  This is probably because I had just changed bars and risers and was attributing the vibrations to what had just changed.  The vibration JoeValkIS felt last summer were mostly in the foot pegs.

From easy and free to more difficult and expensive...

I didn't have any new vibrations or noises when I installed my Ultimate seat w/ driver's backrest.  That said, I would give Des a call to see if anyone else has experienced the same symptoms that you are. 

If the only thing you've changed is the seat, put the other one on and see if the vibration goes away.  Hopefully it will and you'll only have to isolate the source at the seat pan / frame interface.  If it doesn't go away and the vibrations are speed-related, not rpm-related, check to see if any lead weights have fallen off your wheels. 

If the vibration persists, use it as a good reason to do a final drive maintenance and pull the driveshaft and u-joint.  Before doing that, you might go ahead an order a u-joint to have on hand.  If your u-joint is OK on inspection, put it back in and keep the new one on the shelf for later. 

Good luck in your search.

[Daniel Meyer]

Valks are pretty smooth. I think it's her way of telling you, "Hey boss! Check some stuff out!"

[Old Geezer Richard]

  I don't have that Zinger feeling with my stock or in the foot pegs for the most part my old Fat Lady is still smooth ....  matter of fact Dave I would say that the vibration started about two months ago + or - ......  now I have replaced my risers with the La Monster risers back in the spring of 2009 and really like them  ....  let define what I am feeling , its not a run of the mill vibration like at the handle bars the best way I can say , its feels like holding on to a high speed electric drill and that feeling you get in your hand sometimes ... its just right at that slit where the backrest slides in  when I am getting on from 1st to 2nd gear only nothing at all in the higher gears ....  Ill put my stock back on today and run it thru the gears  and see if anything has changed ....  now I would have to admit I am behind my maint. of checking the splines by about 1500 miles since I went Darkside , but the moly paste has always been wet .... but you know Dave I'm kinda concerned about the u-joint etc. because my old Fat Lady has about 75,000 on her clock with never any major or minor problems  ......  she has been a hell of a bike ... well its time for carb. syncing , adjust the valves , fluid change and better ck the drive line if I know whats good for me !!!! RIGHT DAVE  Thanks everybody for your input .... Hey Dave I'm really glad you made home OK from Hotglue's .....