U-joint question

[ThinRedPaste]

Hey all, I've poked around this board from time to time since I got my valk 2 years ago, but I hadn't registered to post until last night, because I need to ask a question.

My bike recently developed a problem where it would make a loud thwack whenever the load on the drive shaft changed from acceleration to deceleration or vice versa.  Not a clunk, I'm talking a metal on metal smack like banging two hammers together, and the impact could be felt in the footpegs.  Sounded like it was coming from the u-joint, and having read about u-joint problems here and on other forums I decided to check it out.  I pulled the bike apart and took the u joint out, but I didn't find what I expected.  There's no twisting play in it whatsoever, but it has almost no resistance on the x members; it just flops around on both axes.  Having not really messed with any u joints before I don't know if that's normal, but I doubt that it is.  Especially since the edges of the yoke and the inside of the swingarm both look banged up.

So the question is: how loose/tight should a Valkyrie u-joint be?  Also, should I be worried about any other parts of my driveline in particular?

[Joe Hummer]

The u-joint should be real tight.  Now, a little slop...is to be expected as the u-joint wears. 

Other areas to check...

Pinion Cup...which you will find when you take the final drive off to get to the u-joint.  These are known to wear out...especially if the holes in the bottom get plugged with grease or the seal on the driveshaft slips up the shaft and leaves the cup open.  This would cause a metal on metal sound when getting off and on the gas. 

Wheel Dampers...which you will find when you remove the rear wheel.  The drive flange slides into the dampers.  These wear out from normal use.  If they are loose in the wheel, they would be felt...not so much heard. 

Shoptalk has a few good articles about removing the wheel, final drive, and u-joint.  The Honda Manual shows a LOT more work than needs to be done.  If you are not familiar with the page, take a look at it.  Link is at the top of this page.

Joe

[Ricky-D]

Especially since the edges of the yoke and the inside of the swingarm both look banged up.

You have identified the noise maker.

Now you should identify the cause.

Are you using aftermarket rear shocks on your Valkyrie?

It's possible that the spring that resides on the driveshaft is "out of spec".

***

[ThinRedPaste]

shocks are stock.  What do you mean by "out of spec?"

Also, i'm going to go check out the pinion cup and whatnot since I've already got the wheel and final drive off the bike, I'll post my findings shortly.

edit: found a new problem: the drive shaft is either bent or crooked in the pinion cup and i can't get the sucker loose.  Got some penetrating oil hopefully soaking down into it right now.  what I can see of the splines does not look promising.

[Ricky-D]

Well there has to be some reason for the inside of the swingarm to have been "banged up"

There is an engineered clearance built into the whole arrangement.

The only thing I can think of at this moment that would be the cause of what you report is the u-joint is causing the "banged up" appearance.

How this can happen is the u-joint is being forced to run outside of it's designated place.

As I read it the causes for this running out of place could be twofold.

1) The swing arm is not is the proper attitude with relation to the motor while running causing the u-joint to hit the inside of the swing arm.  The rear shocks are the controlling mechanism for maintaining the proper attitude of the swingarm.

2) The spring on the driveshaft is there to keep the u-joint in and snugged up on the output shaft of the motor. Any reduction in the spring pressure will allow the u-joint to wander off the output shaft and simultaneously reduce the clearance between the u-joint and the inside of the swingarm.

There may be more although probably more remote causes for what you report.

You say the u-joint is basically Ok if i read your post correctly.

If you are not recognizing the u-joint as being bad, then that can most assuredly be your problem.

***

[ThinRedPaste]

Well, the output shaft seems to be messed up in general.  looks to me like the splines aren't lined up between it and the pinion cup (ie: splines are damaged and jammed against each other), and it seems to be well and truly stuck in there.  It also appears to not be straight - the other end visibly wobbles if i turn the shaft.  Can't tell at the moment if the shaft is bent, or if its just jammed in the pinion cup crooked.  That sounds like a cause for the u-joint to get out of whack too.  

As far as I can tell, that spring is fine.  I can barely even compress it.

[Chrisj CMA]

Well, the output shaft seems to be messed up in general.  looks to me like the splines aren't lined up between it and the pinion cup (ie: splines are damaged and jammed against each other), and it seems to be well and truly stuck in there.  It also appears to not be straight - the other end visibly wobbles if i turn the shaft.  Can't tell at the moment if the shaft is bent, or if its just jammed in the pinion cup crooked.  That sounds like a cause for the u-joint to get out of whack too.  

As far as I can tell, that spring is fine.  I can barely even compress it.

The output shaft is part of the transmission.....its what the u-joint mounts to.  I think you are saying the drive shaft splines going to the pinion are toast.  This is not un-common because some neglect removal of the final drive to inspect and lube this area.  Its a fairly cheap fix.  New drive shaft....use all the old parts except the oil seal, get a new one.  and a new pinion cup.  easy R/R

[Ricky-D]

It doesn't seem reasonable that a drive shaft/pinion cup problem can cause damage to the swingarm in the area of the u-joint as reported by the OP

That is if the damage is current or maybe it is from a previous problem with a bad u-joint.

It's all in how well the "problem" is investigated and reported.

I mean there are a multitude of possibilities:

Try this one,,,, maybe the four nuts are/were loose that tie the pumpkin to the swing arm.

It really up to the competence of the person reporting the problem.

***

[Joe Hummer]

Especially since the edges of the yoke and the inside of the swingarm both look banged up.

You have identified the noise maker.

Now you should identify the cause.

Are you using aftermarket rear shocks on your Valkyrie?

It's possible that the spring that resides on the driveshaft is "out of spec".

***

Rick,

This can happen from trying to rotate the tire while the shocks are removed.  You should never get enough slack in the u-joint (without it completely destructing) to come in contact with the swingarm. 

Joe

[Chrisj CMA]

It doesn't seem reasonable that a drive shaft/pinion cup problem can cause damage to the swingarm in the area of the u-joint as reported by the OP

That is if the damage is current or maybe it is from a previous problem with a bad u-joint.

It's all in how well the "problem" is investigated and reported.

I mean there are a multitude of possibilities:

Try this one,,,, maybe the four nuts are/were loose that tie the pumpkin to the swing arm.

It really up to the competence of the person reporting the problem.

***

Now you stoop to calling the OP incompetent.  Man dude, you need to go ride and leave the guy alone.  I think its totally reasonable assuming (for whatever reason) the pinion splines are shot and causes the drive shaft to rotate in an unbalanced way......the u-joint has the least clearance and it wouldnt take much contact to leave a mark.  

New pinion cup and drive shaft will fix you up.  If you cannot cause any roational play in the u-joint, and its splines are crisp at both ends its probably not the problem.

[Blackduck]

The shaft has a clip on it which can make it a little difficult to remove from the pinion cup.
Needs a good tug to free it.
Get it out, clean and inspect all parts.
Ignore some of the above comments, it is your ride and only you are there to inspect what is the problem. There are many knowlgeable people on here but  also some not so on the ball and have their own opinions which are voiced very loudly.
Go slow, clean and inspect and come back with your findings.
Uni's can be loose but if there is no sign of excess movement I would be looking for another problem.
Cheers Steve

[ThinRedPaste]

That's the thing, I AM incompetent.  I'm trying to learn this stuff, but I only sort of know what I'm looking at.  That's why I posted here for help.  

The drive shaft and pinion cup are definitely shot, no two ways about that.  The shaft is sitting at an angle such that it would almost hit the side of the swingarm itself, u-joint or no.  the u joint itself has good splines and no rotational play.  I was worried about how loose it was but I guess that's not a problem.

I just can't get the drive shaft out of the pinion cup, the splines are jammed against each other real, real good.  in addition to being crooked, the shaft is turned so the splines aren't meshing correctly.  they're halfway smashed against each other.

[Chrisj CMA]

Since you know they are both shot......clamp the drive shaft it a vise or something similar so the final drive is just off the ground and then place a soft blanket or towel underneath it.  The drive shaft should be straight up.  Then use a flat steel object to place over the edge of the pinion cup and give it a few good whacks with a mallet, it will come off

[Jabba]

I always use a wrench that is bigenough to go around the skinny part of the driveshaft, and small enough to NOT go around the fat end of it, and use that and a BFH to knock it out of the final drive. 

If you do that, you'll be able to beat it out of there just fine.  IMO.

Jabba

[Michvalk]

Where do you live? If we knew, maybe someone close could stop by and help you. We have a number of members that like to work on these bikes, and know which end of the wrench to hold on to

[Chrisj CMA]

I always use a wrench that is bigenough to go around the skinny part of the driveshaft, and small enough to NOT go around the fat end of it, and use that and a BFH to knock it out of the final drive. 

If you do that, you'll be able to beat it out of there just fine.  IMO.

Jabba

Dang Jabba that sounds like abuse.  Such a rough way to handle good parts.  I do several guys final drives/rear wheel R/R and all I have to do is give it a tug at a slight angle (off from straight out) and they pop right out.......learn to me nicer on them parts

[Blackduck]

Points to consider, You think the shaft is toast so go with Jabba's BFH, a good whack cannot  do any more harm if that is the problem.
There are many opinions in here, most are good but there are a few that are a little over the top.
Get it apart, clean and inspect and then let us know what you find, Pic's are good as they can show more than what you are trying to say. Don't be fixated on the coupling, have a good look at the whole driveline.
Go slow and steady.
You are not incompetent by any means as you have already gone where many others would not have even tried.
We will help.
Cheers Steve

[Blackduck]

Ok,
Chris,
I have to agree. They usually come apart with a little twist and yank but without being there maybe a little harder force is called for.
Having done so many CV joints I am used to giving the outside part a good whack to disassemble the units..
He is having a go at solving his problem and the least we can is help him  as much as we can.
As per a previous reply he maybe in an area that someone can give some hands on help.
Cheers Steve

[Chrisj CMA]

Ok,
Chris,
I have to agree. They usually come apart with a little twist and yank but without being there maybe a little harder force is called for.
Having done so many CV joints I am used to giving the outside part a good whack to disassemble the units..
He is having a go at solving his problem and the least we can is help him  as much as we can.
As per a previous reply he maybe in an area that someone can give some hands on help.
Cheers Steve

Chill out Blackduck.  If you read my posts you will see I suggested more force on the buggard up parts ThinRedPaste is working on to get them apart, but for Jabba who was talking about working on his own good ones I though less aggression would save some wear and tear

[Jabba]

I don't like the idea of dropping the final drive ANY distance.  My way leaves it solidly on the ground.  It only takes a TINY tap with a mallet to get it apart when things are right.  He says his ain't right and is JAMMED together.  Use the inertia of the heavy final drive, and whack the driveshaft out of the pinion cup.  It would barely even scratch the driveshaft.  And even if it did, it wouldn't HURT anything.

No one has mentioned... is it POSSIBLE that the joint between his u-joint and output shaft is whacked and allowing the u-joint to get so eccentric as to hit the inside of the swingarm?

I PM'd him and asked him to call me.  No word from him yet.

Oh... and no hard feelings from me here Chris... I am not offended nor do I mean any offense to you.  We all have our own ways of doing stuff.  None of them are necessarily wrong.

Jabba

[Blackduck]

Hey Chris,
I'm chillled
Just saying occaisionally a heavy handed approach is required.
I have seen a lot of postings in here and only arc up if they are putting people down or are just not right.
Best part of a free world we can all have our say, right or wrong but if not right we have the obligation to say so.
A  gallon or  so of beer, 1/2 bottle of red and the night here is going nicely
Cheers Steve

[ThinRedPaste]

after several more hours of vise clamping, hammering, wrenching, and everything else mentioned here, i've made basically zero progress.  this sucker does not want to come out.  It wobbles a little now, but it still wont let loose for anything.

Also, I checked the shaft out of the transmission, and its a-ok.  zero slop, excellent splines.

I've got to get away from it for a little while, frustration is maximum and energy is minimum.

[Blackduck]

MMMM,
you definitely have a hard one.
As per previous postings where are you? There are a lot of members around the world the will help out if they can.
There is a wire spring/circlip on the shaft that holds it into the pinion cup.
Normally there is some resistance to the shaft pulling out of the pinion cup but not that bad.,
Can you pry the seal out of the pinion cup and see what it looks like inside?
Again pic's will help.
Cheers Steve

[Patrick]

It sounds to me like the u-joint is OK.. It should 'wobble' freely after its been run for awhile.. Some side to side movement is normal also.. What it shouldn't do is have any any rotational movement/slop/slack..
You mentioned there was damage to the u-joint yoke and swing arm.. That shouldn't happen.. Have you checked the operation of the swing-arm?? Its only held by 2 bearings which should be snug.. You shouldn't be able to get any side to side movement from those bearings.. They're usually are trouble free..
The drive shaft is held in by just a spring clip.. Twisting, turning and pulling like crazy usually allows the shaft to come free.. It sounds as though yours is rusted in place and doesn't want to move.. I wouldn't worry about about putting a big-ass [technical term] clamp on the shaft and hitting it with an even bigger-ass hammer,, as mentioned.. That shaft is hard as hell,, so its hard to hurt.. Once its out though,, check to make sure it runs true.. As mentioned,, the pinion cup is just held in with a retainer nut.. An air wrench is pretty much needed to remove it though.. Don't worry about it,, its easy,, and,, its hard to screw something up..  Have a couple beers and try again..  Keep us informed,, we'll get it fixed..

[salty1]

I'm real anxious to see how this turns out. 

[ThinRedPaste]

the shaft isn't loose in the pinion cup.  or rather, it wasn't.  It took downright violent hammering to get it to even budge.  Now it wobbles a little, but even with two guys wiggling the thing and pulling for all they're worth, it still isn't even thinking about coming out.  I've never seen anything stuck in anything the way this thing is stuck. 

I had already checked all that with the u joint.  The u joint has zero end to end play, or play in the splines at either end.  it's only loose on the axes that its meant to move on.

[Jabba]

Put a crescent wrench around the skinny part of the driveshaft.  run it tight to the skinny diameter and then move the crescent to the end furthest from the final drive.  Then hit the crescent AWAY from the final drive.  It should transfer that linear energy directly to the stuck shaft/pinion joint.  Beat it till it comes apart.  Even if you ruin the shaft ... it's already toast now anyway, and it's only $75 to replace it. 

Beat it till it comes apart.  It'll be apart and your frustration level will decrease.

Jabba

[ThinRedPaste]

tried that too.  no dice.

is it possible to get the pinion cup out without being able to access that nut inside it?  can I pull more parts out with it and come at it from the opposite end?

If you guys are having trouble visualizing what my drive shaft and splines look like, its probably because it isnt even remotely imaginable that they could ever be this perfectly anti-meshed.  i don't know the real terminology, but if you say splines have ridges and valleys, and that the ridges are supposed to mesh into the valleys, then what i've got is ridges almost perfectly centered on opposing ridges.  if not for it being crooked, they would be perfectly centered.

as for where I am: I'm about 30 miles northeast of raleigh, NC.

[Jabba]

You can beat them apart.  You can you can you can.

I swear you can.

I don't know how to get the pinion cup off without taking the shaft out.

Why not grind the pinion cup apart?  That should get it apart.  They are both toast anyway.  And angle grinder and go to town...

Jabba

[ThinRedPaste]

I was just out there beating on it for the last hour.  its too damn stuck.  I might have to cut it apart.  or melt the bastard with torches.  or take the whole final drive and throw it in the damn lake.

[Jabba]

oh... don't do that... ship it to me.

Sorry about your frustration.

Ease off a bit and get the grinder out...  There is no stuck that can withstand a grinder.

Jabba

[lee]

Since its already toast there is one other thing you mite try.
 TWO PIPE WRENCHES,  hold the pinion cup with one and twist the drive shaft with the other one.
This should alow you to move the splines back off each other and loosen things up.

[Patrick]

Yep,, they're right.. A grinder will work.. Cut around the cup.. That'll also give access to the retainer nut.. Both parts are probably bad anyway..

[Jabba]

Since its already toast there is one other thing you mite try.
 TWO PIPE WRENCHES,  hold the pinion cup with one and twist the drive shaft with the other one.
This should alow you to move the splines back off each other and loosen things up.

That's a good idea.  I'll bet the parts are so hard though that the pipe wrenches won't bit.

Plus, if it's as tight as he describes, where a BFH banging on it for an HOUR won't budge them... good idea though.

jabba

[Ricky-D]

If you cut the pinion cup to release the drive shaft you reduce the ability to hold the assembly when time comes to remove the pinion cup nut.

Banging too hard on the drive shaft can lead to damage to the pinion bearing!

keep working the drive shaft in the pinion cup, plenty of lubrication will help.

When you get the unit and shaft apart you will see how it is held together and how crummy it is.

I still do not consider the pinion cup/drive shaft connection to be your problem.

That will not and does not explain the previously stated damage to the u-joint and swingarm.

***

[ThinRedPaste]

shaft and cup are out.  Had to cut a slot in the cup and then pry and hammer to get the shaft loose.  Apparently the rust was all that was holding it together for quite a while - the splines are totally gone.  The bike has 130k miles on it and from the looks of these parts, the shaft has never been out of the pinion cup in that entire time.  Seems like they went bad and got unbelievably stuck, which is to say they were so stuck that they continued to turn and drive the bike, and then just recently got further crooked and out of whack, which caused the u joint to run way, WAY off balance.  We're not talking about a little bit of an angle, here.  The front of the shaft was somewhere in the vicinity of an inch to the side of where it should have been.  I can't believe the bike kept moving like this.  Even if the u joint didn't exist at all, the shaft itself could have conceivably hit and scraped the inside of the swing arm.  So yeah, Ricky.  This totally caused it.  The other nearby parts have been checked out by my father, who knows a lot more about this stuff than I do.  He says they're good, and if he says it, its correct.

On the plus side, a local shop has the parts I need for just over $100 total.  On the minus side, I can't afford to pay attention right now.  Hopefully I can sell off a few collector's items I have lying around and get the money together.

[HayHauler]

I was just out there beating on it for the last hour.  its too damn stuck.  I might have to cut it apart.  or melt the bastard with torches.  or take the whole final drive and throw it in the damn lake.

Sorry to laugh WITH you TRP, but I have been to this point a few times...  This description, after reading all of the posts, made me laugh out loud here at work... got some funny comments from co-workers.

Glad you got it apart.
Check your PM's.  (My Messages) near the top of this page.

Hay 
Jimmyt

[Patrick]

Good.. Glad to hear its finally apart..  It should certainly go together a whole lot easier..

[salty1]

Your persistence has helped us all. Thanks! Any pics?