Vibration on decel

[Treb]

I am noticing a vibration around 20-30 mph when decelerating. I can feel in in the frame through the floorboards and even up into the seat. It doesn't seem to be related to engine rpm or braking because it happens in neutral and without applying brakes. I'm leaning toward a wheel bearing and or the drive shaft, are there any known chronic issues to look for?

[Du-Rron]

I am noticing a vibration around 20-30 mph when decelerating. I can feel in in the frame through the floorboards and even up into the seat. It doesn't seem to be related to engine rpm or braking because it happens in neutral and without applying brakes. I'm leaning toward a wheel bearing and or the drive shaft, are there any known chronic issues to look for?

 

 

https://www.venturerider.org/forum/forumdisplay.php?14-Royal-Star-Venture-and-Royal-Star-Technical-Library-(-99-13)-READ-ONLY!

[cowpuc]

After double checking rear tire condition, air pressures and exhaust system contact to frame issues,, I would proceed to video 1 and if that didnt help I would look into video 2.. If you open it up to check the drive shaft u-joint, also double check drive shaft connections for fracture at the stem nut.. I never encountered a fracture on my 1st Gens but, if memory serves, @videoarizona had a fracture that resulted in the a similar vibration to a bad u-joint and that sounds like what you may be experiencing = IMHO of course..

 

 

[videoarizona]

Yep..I had a drive shaft failure on my 89.

 

There were two types of failures in the drive shaft area, both caused (we think) by metal fatigue or improperly heated bolts/gears....etc..

 

The 1st involved the bolt that holds the ujoint on to the drive gear. This is on the front end of the drive shaft. The bolt shears off...leaving the bolt head to sit inside the ujoint. Nothing else happens as the ujoint can't go anywhere as it's captured by the drive shaft and still moves the bike as it's a splined joint.

 

The 2nd was my failure. The bolt at the OTHER end of the drive shaft broke off. Again...the joint is captured by the shaft and continued to move the bike.

My symptoms were a whine upon deceleration with a slight vibration. This doesn't sound like what you are experiencing at all.

 

What it sounds like you are experiencing may be a bearing failure due to inadequate grease or simply the pins @cowpuc shows in the video are dry as a bone. If you take the wheel off and clean those pins and the inserts they sit in...then grease them up...your problem might be solved.

 

The other issue is check the front wheel bearings. Sometimes these go bad from improper lubrication as well.

 

The idea of tearing both the front and rear apart just for grins...is a good one. Because you need to know the condition of everything in the bike. Establishing a baseline of service makes it so much easier for you to keep tabs on what needs to be done.

 

These bikes are serious long haulers. They will go for years without breakdown as long as a little bit of maintenance is done to them.

[Treb]

Thanks for the tips fellas that's exactly what I was looking for, now I have a starting point.

[Treb]

So just to wrap up this thread....I noticed this vibration after I changed the rear tire and was sure it was something to do with that and it was not. I had also adjusted my home made HD muffler mounts while I had the wheel off and one of the mounting brackets on the muffler was contacting the frame. I adjusted that bracket and took it for a spin and all is well. Thanks again for the tips....Ya learn something new every day if you pay attention I guess!!!