pulsating feeling in the back when decelarating.

[Ben1704]

Hello
I am getting a feeling in the back of the motorcycle when i decelerate,  It feels like when your disk brakes on your car are warped and  you apply the brakes you get that pulsating feeling.  The problem is that is does it no matter if I apply the brakes or not if I pull the clutch in or not.  It does it or I notice it as soon as I let go of the throttle and slow down around 25 mph. 

Note there is no special noise or vibration that I notice and it does not do it when I accelerate even at slow speed.  U joint?  Final drive? Bearings?

[Chrisj CMA]

Without knowing age and miles of your bike its hard to say.  When was the last time the rear end was serviced.  Are you sure it was done right.  Is the boot at the U-Joint in good shape?  How many miles since the last tear down of the rear end?  How old are the drive dampners?

The answer to all that will provide big clues to what is going on

[Ben1704]

It's a 1999 with 29 thousand miles.  the boot is in realy good condition looks newish

I just bought it 3 weeks ago and do not have a maintenance record.  I am also new to Valk.  I have had 2 other GL standars before (82's)

[Jess from VA]

It may be the Ujoint or a left rear wheel bearing (under the likely suspects category).  I've had the entertainment of one each going bad, at different times.

A way to check for Ujoint (or other) driveline slop is to roll slowly along in 2d, and just goose the throttle a bit; on off quickly, roll, repeat.  You are not trying to break anything, just to accentuate any looseness in the drive train.  Generally, if the Ujoint or rear bearing is going, it will (eventually) begin to give a more pronounced vibration or thumping in the pegs, and crunchy clunking or grinding noise as well.

Your low miles would not indicate either, but who knows. Using a pressure washer at the wheel bearings is also bad business.  

Keep riding and checking and listening, and maybe do not go too far into the wild blue yonder when doing so.  

My Ujoint went south close to home but the wheel bearing was in BFE and the last 20 miles limping along at 32mph was noisey, grindy worry  (to a metric dealer that specialized in ATVs and did not want the work, and asked if I could come back next week).

[TJ]

first thing I would do is check your tires...

[Chrisj CMA]

With that low of miles.....I agree with TJ's tire comment as the first choice.  If you can put it on a lift, get the rear wheel off the ground and try to move the wheel side to side (grabbing the bottom) if it moves it will be very slight like a "tic tic" that would mean a wheel bearing is going bad, most likely the left.  Also see if the wheel free spins well while on the lift (in neutral)

I would also try to get a look at the pistons in the brake caliper and see if they could be dirty or possibly locked up.  See if the rotor is either warmer than the fronts after stopping or has unusual looking wear.

I wouldnt expect major drive line parts yet unless some sever neglect or misuse is suspected.

[3W-lonerider]

at 29,000 miles..thats about the time for the wheel dampners to start getting loose. those having play will give you a pulsing feeling. also a bad rear tire.

[Hoser]

When my drive shaft, pinion, and ujoint went out, I had a pulsating vibration as described and through the foot pegs.  I tried to baby it back to the rally site but did not make it.  Luck had it that I have the AMA tow in for life members at no cost.  Got back to the rally site and a guy that trailered in from Topeka, where we both live,Said he would tow my bike home if I would ride his bike back home.  I did, it was a near new  1200R Beemer sport bike.  Only good thing that happened all weekend.  Hoser    

[old2soon]

Also check upper shock bushings. When you take out the bolt and washer SHOULD be dead center. IF not-purchase new ones and install. RIDE SAFE.

[Ricky-D]

Aw, hell, there's nothing wrong.

Go ahead and ride it.

You're worrying unnecessarily.

If the back tire looks good, you're Ok!

***

[salty1]

Aw, hell, there's nothing wrong.

Go ahead and ride it.

You're worrying unnecessarily.

If the back tire looks good, you're Ok!

***

Bad advice until few things are checked out as pointed out above. Is it possible that the drive splines and pinion have never been serviced. Do you know who the PO was?

[Quicksilver]

Maybe change your left rear wheel bearing, easiest to do and will need to be done anyway. Sometimes when they go they start to spin in the wheel rather than rotate as they should. Many of us have gone to double row bearing to avoid that problem. Even then they wear out and need to be replaced. Most noticeable when leaning around corners at slower speeds. Feels like a brake is being applied slightly.

[Ben1704]

thanks all i have a list of things to check now.  will probably change the bearings no matter what since i'm pulling the rear wheel off.

I had it up on the jack and spun the whell every thing is quite and there seams to be no play. so thinking may be a flat spot on the tire? is that possible.

unfortunatley i do not know the  previous owner  not sure how i could find that out

[pancho]

Like was mentioned above, the wheel dampers need to be looked at,,  They can certainly go much more than 29K, but they are 15 years old and made from a rubber like compound that has volatile compounds that will gas off and lead to them getting hard and shrinking......  with that said,, unless the problem is bad enough to get your attention, I go along with RickyD and would not spend my time chasing ghosts.

Look, all the above mentioned things need to be looked at as routine maintenance, especially if you have just gotten the bike, and it is still winter,, but I would not get anal about it.

[sandy]

thanks all i have a list of things to check now.  will probably change the bearings no matter what since i'm pulling the rear wheel off.

I had it up on the jack and spun the whell every thing is quite and there seams to be no play. so thinking may be a flat spot on the tire? is that possible.

unfortunatley i do not know the  previous owner  not sure how i could find that out

Rather than flat spot, it's more likely the tire could be delaminating. You haven't mentioned tire brand or pressures you keep. At 29K, I'd doubt a U joint. After replacing my left rear bearing at 40K, I've had no more bearing issues at 140K now.

[Ricky-D]

Have you considered just to continue riding it and paying attention, to whether your "bike problem" improves, stays the same, or gets worse?

I mean, all the Scary Mary's would have you performing all kinds of processes to the bike, spend untold amounts of time and money, replacing scads of parts, but would not be willing to own up to any responsibility for unnecessary and unneeded expense and replacement of parts.

It's easy to do since this is a forum and there are no limits to what can be suggested by any kind of member.

The problem is most likely related to the tires as has already been suggested in previous postings.  Why ignore this advise?

Now, whether you are just looking for some justification to perform some unneeded modifications, or actually do feel you have a problem, and would like to find a way to confirm you actually do have a problem, starting to make changes without correcting the underlying problem will just end up with a quagmire of unsatisfying results and nothing will be corrected.

Ride the bike. Get used to the bike. It's old and probably has some quirks.

To start down a path to which you cannot see the finish will ultimately result in you getting rid of the bike because of the unhappiness that you will have no one but yourself to blame. Be a little smart. Use a little wisdom. 

***

[hubcapsc]

Be a little smart. Use a little wisdom.

 Yea! 

It's a Valkyrie, it should be smooth as silk and not quirky at all...

You, or someone you trust, should probably ensure all that rear end stuff (final drive,
drive shaft, universal joint) is OK, and you should check your bearings.

With your wheel off, you can put your finger (I usually put a rag or paper
towel around my finger to keep from just slipping on the grease) in the
bearing and turn it... it should seem perfect and smooth.

Someone posted a picture on here (I can't find it) of them (some very strong person  )
supporting the whole wheel by the axle, with the axle inserted just far enough to be
supported by one bearing, and then turning the wheel. If that makes sense, and if you're
strong enough to do it, that ought to amplify any roughness in the bearing enough for
you to feel it.

Whatever it is, it probably won't be that hard to identify or hard to fix... that it might be
the tire seems like a good idea too...

-Mike

[Ricky-D]

Hate to get off topic here, but I never though that was any kind of a reasonable test of a bearing. Mainly because it forces the bearing races to rotate in such a manner that is not normal to the running condition of the whole bearing assembly.

I'm not against checking the bearing for smooth running operation, but I just don't think this is an accurate and representative test and to me, it (the test) has the definite possibility of provide a false result, besides introducing unnecessary and unusual forces to the bearing housing in the wheel.

***

[Bigwolf]

Hello
I am getting a feeling in the back of the motorcycle when i decelerate,  It feels like when your disk brakes on your car are warped and  you apply the brakes you get that pulsating feeling.  The problem is that is does it no matter if I apply the brakes or not if I pull the clutch in or not.  It does it or I notice it as soon as I let go of the throttle and slow down around 25 mph. 

Note there is no special noise or vibration that I notice and it does not do it when I accelerate even at slow speed.  U joint?  Final drive? Bearings?

That sounds like the way my 98 standard felt with about 25k miles on it.  The drive shaft and pinion cup were just about one twist of the throttle from complete failure.  I was very glad I pulled it down and fixed it when I did.  It appeared that the problem had started when a previous mechanic had damaged the shaft seal during maintenance.  I posted my find with photos here     http://www.valkyrieforum.com/bbs/index.php/topic,36763.0.html

Bigwolf

[Ben1704]

frist thing i did as TJ and 3w mentioned i checked was tire pressure when doing this i found a electircal staple in the tire.   now the local shop said i cant run an inner tubes on that mortocycle.  I cant run inner tubes on Tubless tires.  I kind of don't think it's true since on my other Honda shadow Sabre i'v had inner tubes for 3 years.

any opions on that they want aroud 400.00 out of the door all included for new tire installed

[old2soon]

frist thing i did as TJ and 3w mentioned i checked was tire pressure when doing this i found a electircal staple in the tire.   now the local shop said i cant run an inner tubes on that mortocycle.  I cant run inner tubes on Tubless tires.  I kind of don't think it's true since on my other Honda shadow Sabre i'v had inner tubes for 3 years.

any opions on that they want aroud 400.00 out of the door all included for new tire installed

     If we are talking a rear tire patch it from the inside. This IS NOT for every body but a lot of us with these Valkyries we ride cost is part of the reason we have gone D/S-car tire on the rear. There is a wealth of information here on this application just by doing some research right here on the tech board. IF you end up taking the rear wheel off do the rear end service as you already have it apart. Grease splines 3 new O-rings and new oil in the differential. This also affords the opportunity to look at condition of rear brake pads shock bushings and anything related to the rear of this machine. Finding some body close that has done these things before is helpful and you would be surprised how much help you can get with the offer of a cold beer and a sandwich.  RIDE SAFE.