Is a bit of a clunk in the driveline normal?

[8Track]

Hi all,

My Valk has 52,000kms on it and has been ridden like a baby for the last 20,000 since I bought it. I have noticed that in high gears ( 4 & 5), if I accelerate from lowish rpm's (around 1,500) I feel a bit of a clunk as I roll on. Similarly if I close the throttle I can get a clunk if I'm not smooth with it.

My rear wheel dampers have been replaced, wheel splines, pinion cup, and the top end of the shaft are all properly lubed and appear as new.

Is there anything else that could be causing the clunk that needs to be checked, or is it normal to experience a clunk in shaft drive bikes?

Thanks,

Mark

[R J]

From what you are describing, it sounds like the damper bushings are starting to get loose.

You baby this bike and she is going to rebel on ya and give ya all kinds of noises.

Start riding it like ya STOLE it, it likes to be abused.

 

[8Track]

RJ - do you mean the wheel dampers when you say damper bushings? These have been replace recently. Shock bushings also replaced.

[R J]

That is what I'm talking about.

New ones can be loose, tight or SUPER tight.

I'll dig around out in my shop and see if I can find the part # for the ones I always bought before I went with a Trike conversion.

Sold all those parts off.

[Hook#3287]

Hard to gauge a "clunk" w/o a test ride, but not mentioned is the u-joint.

They usually go out with vibration first, but a clunk could happen.

[gordonv]

My first thought also was the dampeners, but you say they have been replaced. How tight where they (are they) into the rim? Where they the one piece IS, or the older 2 piece ones?

My second guess would be the u-joint. But how long has this been going on for, as once it starts making enough noise, it goes quickly and you are left on the side of the road.

[8Track]

Thanks all,

The dampers were a tight fit. Had to seat them with a rubber mallet. The clunk is felt moreso than heard and it is fairly slight.

Sounds like the only thing it could be is the u-joint. People here mention getting them from HDL. What is HDL??

[Jess from VA]

HDL = Honda Direct Line (parts)

This will be cheaper. (I have no idea about shipping though)

http://www.procaliber.com/oemparts/a/hon/506c2f2bf870023420a31b1c/swingarm

JOINT, YOKE   40200-MZ0-A00   $120.86

(#1)


Never a bad idea to get a new boot too. (#8)

[pancho]

You need to remove the u joint and put it in a vice to really check it out,,, I almost got fooled once by one I removed and it felt good in my hands,,,

http://www.valkyrieforum.com/bbs/index.php/topic,67460.0.html

and put it in a vice and apply twisting on the other end with a pair of channel locks or similar. It should be tight with no play.

However, I believe that some clunks that are heard from the area are a result of our spring loaded drive line being held by torque in an unseated position, then when the conditions change, the drive line re seats into the pinion cup with a "clunk"....   just a theory,,,   but it seems to happen on mine intermittently and I just accept it.

[Jess from VA]

I have no idea if your clunk is a failing Ujoint.  My experience is that it went from a thumping in the footpegs, to a grinding, self-destructing thumping/banging event in a pretty short time (and I was lucky to limp home). 

On the other hand, anyone who owns a Valkyrie and is intending to keep it (forever) would be well served to have a new Ujoint on hand (and a boot), just in case.  Especially if getting hold of one where you live may be difficult (or take a long time).

Are there no Honda bike dealers in Aussie Land?  Dealers in the US are mostly stuck charging (expensive) MSRP through franchise agreements, and most of us do not buy our parts from them (even including shipping from parts suppliers).  But considering shipping to your home, maybe a local purchase is a better deal.  Or maybe Japan?

[Rio Wil]

Sounds to me like you are simply feeling the normal drive line slack from the final drive flange, through the dampers and into the transmission gear lash. You have verified the drive flange and pinion cup splines are OK, if the ujoint has enough slop to clunk at all, it will not be too long before it pukes all over its-self.....but generally you get a vibration warning before hand.

If you want to see just how much total slack is in the entire drive line, lift the rear wheel off the ground, put the trans in 5th gear and then rotate the rear wheel. You will see about 1 to 1 1/2 inches of radial motion.....aggressively rotate the wheel back and forth to demonstrate the clunks in the drive train.....you won't hurt the drive line doing this, clunky shifts or power shifts put a hell of a lot more clunky stress on the drive line than you can do by hand. But, it gives you a feel for normal drive train clunks.  As you go down in the gears, 4-3-2-1, the radial motion becomes less and less.

I don't buy into the concept that if any movement is detected in the rubber dampers that they are worn out, as long as the metal inserts are still attached to the rubber and nothing is torn or cracked, they are serviceable.....after they get to 1/8 inch slack or so, it is nice to install new ones and enjoy a few hundred miles of new cushiness....

As to 4-5 gear at 1500 rpm and rolling on, just a few words......DON'T DO THAT     Admittedly, the engine will pull from that rpm without complaining much.....but think about it.  You are placing prolonged stress on all engine bearing components and in my mind this gives ample time to squeeze the oil film out of the bearings increasing bearing wear.  Oil pressure at that rpm is like 10 psi versus 70 psi at 5000 rpm.....I would rather over rev than under rev this engine....it will last forever just about......it comes with a never ending supply of rpm's ....or so it seems. Its a great bike, drive it and enjoy, you won't hurt it.......

[8Track]

Sounds to me like you are simply feeling the normal drive line slack from the final drive flange, through the dampers and into the transmission gear lash. You have verified the drive flange and pinion cup splines are OK, if the ujoint has enough slop to clunk at all, it will not be too long before it pukes all over its-self.....but generally you get a vibration warning before hand.

If you want to see just how much total slack is in the entire drive line, lift the rear wheel off the ground, put the trans in 5th gear and then rotate the rear wheel. You will see about 1 to 1 1/2 inches of radial motion.....aggressively rotate the wheel back and forth to demonstrate the clunks in the drive train.....you won't hurt the drive line doing this, clunky shifts or power shifts put a hell of a lot more clunky stress on the drive line than you can do by hand. But, it gives you a feel for normal drive train clunks.  As you go down in the gears, 4-3-2-1, the radial motion becomes less and less.

I don't buy into the concept that if any movement is detected in the rubber dampers that they are worn out, as long as the metal inserts are still attached to the rubber and nothing is torn or cracked, they are serviceable.....after they get to 1/8 inch slack or so, it is nice to install new ones and enjoy a few hundred miles of new cushiness....

As to 4-5 gear at 1500 rpm and rolling on, just a few words......DON'T DO THAT     Admittedly, the engine will pull from that rpm without complaining much.....but think about it.  You are placing prolonged stress on all engine bearing components and in my mind this gives ample time to squeeze the oil film out of the bearings increasing bearing wear.  Oil pressure at that rpm is like 10 psi versus 70 psi at 5000 rpm.....I would rather over rev than under rev this engine....it will last forever just about......it comes with a never ending supply of rpm's ....or so it seems. Its a great bike, drive it and enjoy, you won't hurt it.......

Thanks for this great advice. I have been told by a non-Valk owning friend that some "take-up" is normal in shaft drive bikes and not to be worried. I certainly don't get any vibration and the clunk is felt rather than heard.

As for the 1500rpm roll-on, this is done gently and pretty much only when I ride for short periods with the rpms under 2,000 to make sure I have fresh petrol flushing through the slow jets to keep them clear.

Cheers,

Mark