Strange vibration I felt today, that I normally don't feel.

[DutchValkyrieGL1500C]

I'm a bit concerned because when I started the engine today I felt a strange extra vibration while the engine was still idling. When I started riding I didn't feel anything strange in the first 3 gears, it just ran like normal, but I did feel the vibration again in the 4th and 5th, especially when I opened the throttle. It's a very tiny vibration that I mostly feel in my feet. I can't hear anything unusual and I don't feel it in my hands, except when I'm stationary then I also feel it on the steering wheel.

I drove the motorcycle 2 days ago for the whole day and it was perfect, the only thing I did in the meantime was give it a wash and turtle waxed it. Is it possible I maybe dislodged a vacuum cable or something, or that water got in somewhere? I checked all the cables and everything looks fine.

Does anyone have this experience or any idea what I can check?

[Challenger]

First thing, since you said you washed it, check the drain holes for the spark plugs are open and see if one socket is full of water.

[DutchValkyrieGL1500C]

Hey Challenger, thanks for the reply. Yes I checked the spark plugs, they're all dry and all cylinders are working like normal.

[Pluggy]

Examined the coils?  Washing or a strong rainstorm put my 4 cylinder Honda in poor running condition.  Each coil had a crack that allowed water inside.  The cracks were on the "top" side of the coils and had to be removed to see the problem.   

Replacements were not expensive.

[DutchValkyrieGL1500C]

I did, unfortunately I don't have a way of measuring resistance, but they all look fine. Having said that I'm no expert. I've only visually looked everything over. Is there something specific I can check with normal tools?

[Pluggy]

Each crack was large and on the side facing the fuel tank.  If dry, each coil would have probably passed a resistance test.  Once wet, they would not produce the high voltage required to correctly run the motorcycle.

Hope you find the cause of the condition, soon.

[Jims99]

A quick simple test for vacuum leak, spray some starting fluid around vacuum line. Hopefully a small leak, easy fix. There's one coil that's down lower you may be able to see around the top with a small mirror, that's the only one that I think would get wet just washing. Also check grounds and connections.

[hubcapsc]

"strange extra vibration"...



-Mike "ida know..."

[Timbo1]

Just to clarify

1. You felt the vibration sitting at idle while standing still.
2. You did not feel the vibration while moving from 1st - 3rd gear.
3. You did feel the vibration while moving in 4th - 5th gear and more so when you open throttle.


If all that is correct you can eliminate some things like tires, wheel bearings, drive shaft etc.. that are not moving when sitting at idle.

If you open throttle while standing still does the vibration increase with the RPM or change in any way?
If you pull in the clutch while standing still does the vibration change?
While standing still if you go through the gears 1-5 does the vibration change in any gear?


I would use a Mechanics Stethoscope to see if I could locate the source.  Noises and vibrations can sometimes be hard to track down and these are pretty cheap.  https://www.harborfreight.com/mechanics-stethoscope-63691.html

[DutchValkyrieGL1500C]

I called Hans Huijbers today and explained him the situation and he also thinks it's a vacuum hose somewhere that's loose. I checked all the carburator connections but everything looks like new, no tears or faults. I also checked all other rubbers I could visually see, but they're all looking good.

If you open throttle while standing still does the vibration increase with the RPM or change in any way?
If you pull in the clutch while standing still does the vibration change?
While standing still if you go through the gears 1-5 does the vibration change in any gear?

No to all the questions. When I'm idling it seems to stay the exact same etra vibration in all situations.

A quick simple test for vacuum leak, spray some starting fluid around vacuum line. Hopefully a small leak, easy fix. There's one coil that's down lower you may be able to see around the top with a small mirror, that's the only one that I think would get wet just washing. Also check grounds and connections.

Could you explain the starting fluid solution a bit more, what would I see if I spray that?

[Chrisj CMA]

Usually what is frequently referred to as the buzz bolt is responsible for a buzzing vibration at 45 or 50 mph. However it's worth checking. It's one of the three bolts at the point where the upper part of the crash bar mounts. It's the one that goes all the way through to the other side. Look you will see the crossover tube. That bolt needs to be really tight.

[DutchValkyrieGL1500C]

So I took the tank off and checked every possible line and everything looks like new, no wearing or cracks anywhere. I checked every bolt and screw, all good. Strange thing is. When I put it back together and took it for a spin, problem in idling gone. No more vibrating. Allthough I did feel a litle vibration but now in the lower gears. However I'm not sure anymore if this is normal vibrating or if something's up. I think it's time to consult with the experts.

[Chrisj CMA]

I think it's time to consult with the experts.

And who do you suppose they "the experts" are?

[Oss]

Mike "ida know" posted what I was thinking

Had the same issue turned out to be the u joint

If you order one get the boot as well  ( unless you enjoy the words that come out of your mouth while you struggle to get the old boot back on

It is a good spare part to have in the saddle bag

[turtle254]

can you replace the u joint with boot on ?

[RonW]

I see what you mean. Is it possible to pull the driveshaft out through the swingarm with the u-joint stuck on the drive shaft??

[hubcapsc]

The only "trick" I've ever pulled off is reusing the old boot - I rolled
it back on itself like in the video Lady Draco posted, afixed one end
of it and rolled it back into place.

There's people who say you can push the driveshaft back on its spring
and remove the u-joint without removing the driveline. That makes
my brain hurt.

I don't think the u-joint, even if it would stick on the end of the driveshaft,
would come out of the boot, or travel/fit down the swingarm. Many of us have
a hard time getting the driveshaft back onto the ujoint, I'd like to video
the guy looking down his swingarm trying to shove a driveshaft with a
ujoint on the end of it back down the hole and through the boot  onto
the output shaft :-) ...

Removing the final and the driveshaft for cleaning and greasing should
be an "every tire" kind of thing on a Valkyrie, Going to the additional
trouble to look at the ujoint seems warranted every now and then,
especially if you don't find something else to blame the vibration on...

-Mike

[Valker]

New boots appear to be unobtainable

[Chrisj CMA]

You DO have to remove the wheel, final drive and driveshaft to access the U-Joint

You DO NOT have to remove the swing arm. However the u-joint will not slide down the tube of the swing arm. Not even close. It must be remove from the forward end of the swing arm. This necessitates unbolting/moving some stuff in that area like the brake oil reservoir and some hoses, but it can be done and sorry,  yes, the boot has to come off.

[Skinhead]

The u joint can be removed without removing the rear wheel.  The boot must come off.  It's not easy, but can be done.

[turtle254]

The u joint can be removed without removing the rear wheel.  The boot must come off.  It's not easy, but can be done.

Really, and you can reinstall it with the wheel/drive line in place? Please describe the procedure.

[Skinhead]

The u joint can be removed without removing the rear wheel.  The boot must come off.  It's not easy, but can be done.

Really, and you can reinstall it with the wheel/drive line in place? Please describe the procedure.

As close as I remember it:

Jack the bike up and remove the rear brake MC and Pedal and move out of the way.

Pull the boot back and use a long pry bar to slip the u-joint to the rear on the drive shaft while removing it from the trans output shaft, slip the front of the U-joint off the output shaft and remove the boot. 

Slip the U-joint out through the gap between the swingarm and engine.

I rank the difficulty of this process on par with that of changing the alternator, it can be done, but will fight you all the way. 

[Chrisj CMA]

All I can say is I pried the u Joint back to add lube and it was way hard to just get room to get grease. I don't think that thing was going to go back far enough to get removed. I'll take the drive train off.