[cory1848]

Need some help. I posted this over on the Steve Saunders forums as well, hoping I can get some more answers here.

Quick background...
I recently put on a new tire, pulled the drive shaft and relubed all the splines, put everything back together and all seems good.

While doing this I turned the key on to make sure the lights worked, and like an idiot didn't turn it off all the way, left it in the acc position. Well this drained my battery. Had to jump it off car battery (car not running). Got the bike running and took it for a 30 minute spin to charge it up again. All good so far.

However, now at high speeds, 3k +RPMs and 70ish mph I notice a vibration. If I pull in the clutch it like turns the vibration up 4 notches. I thought it was coming from the rear end but now it seems to be getting worse. Going 70 mph down the highway, pulling clutch in and revving the engine to 3.5rpms, the vibration is really noticeable. Seems like it changes with engine RPM, Almost like a cylinder misfiring, or a really bad vacuum leak, although the revving could just be adding to it.

The vibration is most prevalent at 70+mph, at 55 I can still feel it, bit not as pronounced. Anything lower than 2500rpms I can't feel it at all. So cruising at 70mph, seems fairly smooth until I pull in the clutch, then vibration sets in. Revving the engine seems to enhance it, but I am thinking that isnt the root cause now.

I know there is a lot of talk about u-joints going bad but I don't see how this could suddenly appear out of no where just from pulling the drive shaft. Should I pull it again and reassemble?

I will ordering the rubber dampers for the alternator later today and try and eliminate that. With bad rubber dampers, how much vibration would this cause?

So this is everything that I did.

1. New tire, Dunlop E3. - Could that be a cause?
2. Changed Differential fluid
3. Lubed drive shaft splines, new oil seal, moly 60 all the splines except u joint.
3. New exhaust gaskets - Hardly see how this could cause anything
4. Checked wheel bearings for notchiness. (sp?)
5. Reassembled with proper torque specs. Everything went back together without a fight.

Any thoughts? Really stumped here.

Thanks
Cory

 

[budoka]

So is it engine vibes you're feeling or is it tire/balance vibration? If it increases with engine rpm with the clutch pulled in, I think we can rule out balance. If there's one thing that Wings don't do, it's vibrate so.

 

[cory1848]

So is it engine vibes you're feeling or is it tire/balance vibration? If it increases with engine rpm with the clutch pulled in, I think we can rule out balance. If there's one thing that Wings don't do, it's vibrate so.

When I pull the clutch in at high speed, the vibration is very noticeable. I am now doubting myself if the noise increases with rpm. It is hard to tell at that speed.

If the vibration is there when the clutch is pulled in and letting the rpms drop, wouldnt that eliminate it being an engine issue? If it were an engine issue, wouldnt it be present at lower rpms as well? Sitting in neutral in driveway, I can rev it to 3500 and it is a little rough, but that seems like a carb syc issue, not nearly as bad as what I am experiencing on the road.

Looks like I get to pull this crap apart again tonight.

 

[Cantankerous]

The description you are giving sounds like a bad u-joint. If you didn't have it before, you might have gotten the drive shaft installed in a different position and is throwing the balance off.

 

[cory1848]

Been reading up on it some more...Since the tire was new, I am going to check for proper seating. Is that something I can check in the parking lot?

If I cant find anything there, I will rip it all apart again.

I have read that when reassembling the drive shaft into the u-joint, that it should not matter what position it goes back in (no balancing involved) and have read that 90 degrees off causes vibration.

Guess I will find out tonight...

 

[cory1848]

The description you are giving sounds like a bad u-joint. If you didn't have it before, you might have gotten the drive shaft installed in a different position and is throwing the balance off.

So if I don't know the original position from when I originally took it apart, how do I find the balance again? Just guessing? Keep pulling it until I magically get it right?

 

[Cantankerous]

Nothing in the manual states how to align it. I would try rotating it 180 degrees from where it is.

 

[trike lady]

When you dismantled the bike to grease the splines, did you pull the gear case?
Did you put the long side of the U joint towards the front?

 

[DreamWeaver]

When you dismantled the bike to grease the splines, did you pull the gear case?
Did you put the long side of the U joint towards the front?

Are you asking him if he reversed the drive shaft. Front to back and visa versa? Just wondering since I never thought of that. Guess it would be easy to do huh?

 

[trike lady]

Are you asking him if he reversed the drive shaft. Front to back and visa versa? Just wondering since I never thought of that. Guess it would be easy to do huh?

You can remove the entire gear case final drive from the swing arm.
But the U joint can accidentally get installed improperly. The U joint is a separate component from the drive shaft.
It is mentioned in the service manual to leave the four nuts that hold the gear case in place on the swing arm loose when installing the rear wheel and once the wheel is in place tighten them to spec. What I'm wondering is if the gear case was pulled.

 

[cory1848]

You can remove the entire gear case final drive from the swing arm.
But the U joint can accidentally get installed improperly. The U joint is a separate component from the drive shaft.
It is mentioned in the service manual to leave the four nuts that hold the gear case in place on the swing arm loose when installing the rear wheel and once the wheel is in place tighten them to spec. What I'm wondering is if the gear case was pulled.

The differential was pulled. That is the only way to remove the shaft. However, the u-joint was not removed. So there is no way that could have been switched around.

I rotated the shaft and reinstalled it and still has the vibration. NOt sure where to go next... New u-joint maybe? Are these still on back order?

 

[DreamWeaver]

I'm almost inclined to think you have a tire thats out of round. Was there a lot of weights needed to balance the tire?

 

[cory1848]

I'm almost inclined to think you have a tire thats out of round. Was there a lot of weights needed to balance the tire?

Only one small weight on there. Maybe a half oz? When spinning the tire by hand, I can see a little what seems like a bump in the tire, very slight but it is there.

If the tire was out of round or out of balance, would running it on the center stand up to speed still cause a vibration? Or would running it on the stand eliminate that?

Wish I had another rim and tire I could throw on to try and eliminate that. Should I take the wheel back to the dealer and have them rebalance and check for out of roundness? I am thinking the dealer wont be too accommodating with that request.

 

[DreamWeaver]

Only one small weight on there. Maybe a half oz? When spinning the tire by hand, I can see a little what seems like a bump in the tire, very slight but it is there.

If the tire was out of round or out of balance, would running it on the center stand up to speed still cause a vibration? Or would running it on the stand eliminate that?

Wish I had another rim and tire I could throw on to try and eliminate that. Should I take the wheel back to the dealer and have them rebalance and check for out of roundness? I am thinking the dealer wont be too accommodating with that request.

My feelings are that "You paid good money for a good tire, and a good tire is what you want." So, yes, I would take it back to them and have them check it out. I don't think a bump, even if it is small, should be there. Any small bump would/could cause vibes. I guess that running it "up to speed" on the center stand would make it show up but I DO NOT ADVISE doing that. Remember if it comes off that stand with the back tire spun up, you have a 900 pound bowling ball that is going wherever it wants to go. I wouldn't think a dealer or whoever you got the tire from would give you any grief about having them check it out. And...What is the one thing that is totally new here...The tire...You didn't have the vibe before, but now you do.

 

[cory1848]

My feelings are that "You paid good money for a good tire, and a good tire is what you want." So, yes, I would take it back to them and have them check it out. I don't think a bump, even if it is small, should be there. Any small bump would/could cause vibes. I guess that running it "up to speed" on the center stand would make it show up but I DO NOT ADVISE doing that. Remember if it comes off that stand with the back tire spun up, you have a 900 pound bowling ball that is going wherever it wants to go. I wouldn't think a dealer or whoever you got the tire from would give you any grief about having them check it out. And...What is the one thing that is totally new here...The tire...You didn't have the vibe before, but now you do.

Good points. I had the whole rear end apart so I was thinking I screwed something up, but after putting it all back together for the 5th time, it is really difficult to screw it up so that leaves me back to the tire. Hopefully I can make it to the shop in time before they close today.

Will update again later tonight. Thanks!

 

[DreamWeaver]

I am dating myself, but one of the things we used to use to check for a tire out of round was a coke bottle. Put the bike on the center stand, put it in neutral, engine OFF. Set a coke bottle or something of that nature right up next to the tire so that it barely touches the tire tread. We used the lip of the bottle because of sensitivity. Then slowly, with your hand , rotate the tire. If it is out of round, the bottle will rock or fall over as it comes in contact with the out of round spot. Do that with the bottle on the left side of the tire tread and then on the right side. If you are viewing the bottle from the side, you can see the gap between bottle top and tire as you rotate it. So, thats the old way of checking for "out of round" tires. Works on cars, trucks, bikes or just about everything except hovercraft.

 

[cory1848]

I am dating myself, but one of the things we used to use to check for a tire out of round was a coke bottle. Put the bike on the center stand, put it in neutral, engine OFF. Set a coke bottle or something of that nature right up next to the tire so that it barely touches the tire tread. We used the lip of the bottle because of sensitivity. Then slowly, with your hand , rotate the tire. If it is out of round, the bottle will rock or fall over as it comes in contact with the out of round spot. Do that with the bottle on the left side of the tire tread and then on the right side. If you are viewing the bottle from the side, you can see the gap between bottle top and tire as you rotate it. So, thats the old way of checking for "out of round" tires. Works on cars, trucks, bikes or just about everything except hovercraft.

Thats a great tip! Easy enough to test out too! Thanks

So just to double check, any bit of out of roundness, should warrant a replacement?

 

[trike lady]

The differential was pulled. That is the only way to remove the shaft. However, the u-joint was not removed. So there is no way that could have been switched around.

I rotated the shaft and reinstalled it and still has the vibration. NOt sure where to go next... New u-joint maybe? Are these still on back order?

I know at least one person who defied removing the gear case and somehow managed to pry the U joint out, I'm sure it wasn't easy to get in or out and I wouldn't attempt it on anyones bike.
See if you can get the one for the Valkyrie, it's a tad more robust or contact Gary at Lone Star Trikes I know he had some at one time. www.lonestartrikes.com

 

[DreamWeaver]

Thats a great tip! Easy enough to test out too! Thanks

So just to double check, any bit of out of roundness, should warrant a replacement?

Well, there is no such thing as a perfect tire. If there was, they wouldn't have to be balanced. So, in my opinion, if the tire appears to be out of round, I would surely ask for a replacement. If you haven't bent the rim or anything by hitting a curb or something, then an out of round tire will , or can cause a vibration. It has been my experience that when a tire is balanced on a machine, contact with the road is not taken into consideration. It is spun in the air and weights can be added to make the tire appear balanced. BUT, put that same tire on the bike, then drive it and the bump on the tire comes into play. Its the contact with the road that is the difference here. I think you could balance an egg with one of those balance machines, but obviously if you put that egg on the ground, it would not roll smoothly. Same principle applies here. Now, TrikeLady has a valid point and her advice has always been spot on. So, if replacement of the tire dosen't fix the problem, take her advice to heart. She's a smart cookie in these matters. In my mind, the tire is the most logical culprit in this case.

 

[cory1848]

I know at least one person who defied removing the gear case and somehow managed to pry the U joint out, I'm sure it wasn't easy to get in or out and I wouldn't attempt it on anyones bike.
See if you can get the one for the Valkyrie, it's a tad more robust or contact Gary at Lone Star Trikes I know he had some at one time. www.lonestartrikes.com

My bike is a 97, from what I have read, the 97-2000 models had the heavy u-joint, same one as the Valk.

I made appt with the dealer for them to check the tire tonight. If that doesn't fix it, I will order the u-joint. Thanks for the link.