Vibrations in seats

[Balquin]

So I just had my seats redone at Mean City Cycles and they are definitely more cushy. Was noticing I had more vibration in the seats and that is what causing discomfort now. Started to think maybe the engine mounts may be suspect so I started to do some thread searches. Came across the damper might be a suspect as well. It's an 08 with 11500 miles on it. Could the damper actually be in need of a rebuild? I'll probably go thru the process of checking the engine mount torques to eliminate those.
Really want to be able to take longer rides, but with my backside going numb from the vibration it's getting discouraging. I knew v-twins have there normal vibration, but coming thru the seats like that can't be normal. Any other suggestions would greatly be appreciated. Thanks!

[redjay]

Are the rubber bumpers in the bottom of the reworked seat ? I think there are four or five that should be there ?

http://www.ronayers.com/oemparts/a/k...3e47942ee/seat

92075 and 92075A ?

They could have been removed for the rebuild and not replaced ?

[VulcanE]

Mine started having the vibration your describing, I loosened the motor mounts and re-torqued them, didn't help. I removed the final drive and I found the slip joint that connects it to the drive shaft was dry. I greased it and put the recommended 200 ml of grease in the slip joint, put it back together, and the vibration was gone. I do my maintenance when I'm supposed too, and every time I do the swing arm service, that slip joint has little to no grease in it. I don't know what happens to it, or where it goes, but it does.
A couple of times I've gotten that "vibration" between swing arm services, and I'll remove the final drive and take my syringe and put 200 ml of good moly grease in the slip joint, and put it back together, then it's as smooth as butter again.

[Balquin]

I will double check the dampers on the seat. Guess it may be time to learn how to do the swingarm maintenance :p Should learn that one anyway.

[Balquin]

Well the seat dampers are there, looks like a swingarm/driveshaft service is in my near future. No time like the present to start learning!

[VulcanJeff]

I came across this several weeks ago. It seems like a real nice write-up with good photos. I am versed in the process for old BMW airheads and K bikes but can't vouch for how thorough it is on a Vulcan. Looks pretty good though.

http://www.kawasakimotorcycle.org/fo...2-22-07-a.html

[macmac]

Almost 12,000 miles and never a swing arm service yet ? You will want to get on that asap. besides the slip joint there is a U Joint. About 1/2 of these didn't get greased properly at the factory, and are bad. These can eat the yoke, seize locking the rear wheel instantly, and can start vibs like you are talking about.

Also the swing arm has 3 spacers that got almost no grease at the factory, and one poor guy here went so long he had to hack saw the long bolt at the drive shaft tube threads to get the swing arm out and drill the shank end of the bolt too. After that he had to use a air gun impact hammer to drive what was left of the bol in the swing arm out as the bolt was rusted to all 3 spacers bad. Now i don't know how long that took in hours, but my guess is it was a Royal Pain and took him several days to just get it apart.

When i do this I use 2 kinds of grease. For any and all parts with splines I use CV Joint moly lube.
For the long bolt, all sides of all 3 spacers i use marine grade water proof chassi grease.

If this is a 1600 then it has needle bearing in the top ends of the rear shocks and I use moly there too.

If the U joint is dead you get one for the kawi 4x4 things..... As ma kawi says th U J joint can't be replaced on the Vulcan drive shafts but it sure can.

U joint costs about 35 bucks for the part. The drive shaft last i knew was 365 ish
Doubt the engine damper, and semi doubt the engine mounts.

Does the vibration happen with the engine running in neutral full dead stop ?

[Balquin]

Good info thanks! I'll have to pay a bit more attention when the vibration is happening. Yeah, I bought the bike with about 10500 miles on it. No telling what kind of maintenance had been done prior. I finally have the proper jack and an Idaho adapter so maintenance will be a lot easier for me to do now. I remember reading up a bit on that u joint, isn't there one with a grease fitting as well? I'll have to remember to get some grease next time at the store and maybe just get the u joint and change it no matter what. Have a long ride coming up, maybe I should attack the swingarm on my weekend coming up...

[Yellow Jacket]

U-joint info:

http://www.vulcanbagger.com/forums/s...ad.php?t=17405

[Top Cat]

Originally Posted by macmac

Almost 12,000 miles and never a swing arm service yet ? You will want to get on that asap.

I had 88,000 miles on my 07 and had the swing arm serviced one time.
I think it was around 40,000 miles. I still had grease in it
You guys worry to much, go ride the things

[cnc]

If the viberation is coming from something not right in the drive train, then not only would you only really notice it while moving, I would suspect that the seat would not be the only place you would feel it, most likely in the bars and foot rests as well.
Too bad the seat was reworked instead of switched, that way you could switch back and see if the amount of vibration you notice in it changes. Maybe the removal of some foam or density of the foam they used accentuates what you are feeling.