2007 Headshake on Deceleration/Noise in Forks?

[Fred H.]

A longer wheel base should make for a more stable ride at steady speeds, but make turn-in slower. I'm not sure that a longer swing arm implies more or less stability during decel.
The Gen II rear swing arm is longer, but all else remains the same AFAIK, that means that the center of gravity must be different between Gen I and Gen II which will affect stability. The amount of empirical evidence makes it look like something has changed. Guess we need to hear from the ones that have not experienced headshake when new.

The Honda shafties that I've owned all shook, and my V-Max shook. My '04 is the only shaftie that has not had headshake. Me like that a lot

Interesting correlation you made between the shaft and headshake issues.

As for the swingarm, or wheel base, the GL1800 has one of the longer wheelbases amoung production motorcycles, and it has a terrible reputation for the "coast down hands-off-bars" headshake.

Also be aware that many times headshake issues are amplified by the rear end. The longer lever arm on the rear can act to reinforce the oscillations. Sort of like the tail wagging the dog. The longer the tail (and more mass) the more the wag effect.

It may be extremely hard to nail down the exact cause, and I suspect you won't ever be able to blame it on one single thing, but rather a combination of things that all contribute to it, suspension and geometry just being one factor among many that all play into the big picture.

Just for fun, go visit just about any motorcycle board on the internet for any brand or model bike, and type in "headshake" in the search engine and see what you get back.

 

[twowheelnut]

A longer wheel base should make for a more stable ride at steady speeds, but make turn-in slower. I'm not sure that a longer swing arm implies more or less stability during decel.
The Gen II rear swing arm is longer, but all else remains the same AFAIK, that means that the center of gravity must be different between Gen I and Gen II which will affect stability. The amount of empirical evidence makes it look like something has changed. Guess we need to hear from the ones that have not experienced headshake when new.

The Honda shafties that I've owned all shook, and my V-Max shook. My '04 is the only shaftie that has not had headshake. Me like that a lot

Concur. None of my riding buddies with the Gen II's comment about the shake. :dntknw: Maybe an attempt at loading up the front by sliding forward might be enlightening.

As for the Honda shafties; yeah, my GL1800 did the shake and my tech, Jack (the best damned mechanic EVER!) correctly diagnosed the problem as the head bearings. He replaced them with - aw, shit I can't remember now, but his repair fixed the problem.

Side note:

I remember reading not too long ago in MCN that someone in the PNW filed a class action lawsuit over the GL1800 issue...

 

[AGirl]

The rear swing arm is longer which *may* alter the characteristics of the beast.

You mean like it's a bit harder to wheelie?

FWIW, I don't notice any difference in the headshake w/different tire pressures, topcase on/off, sidecases on/off or full/empty. Hopefully I'll get this figured out here shortly though w/my tech (& best damn mechanic ever), Jim.

AGirl

 

[Last Chance]

I'll bet, that sooner or later with the front tire wear every FJR owner will experience some wobble of the bars when letting the bars go upon deceleration.

Sorry if I didn't make my post clear, but my wobble is felt w/o even letting go of the handlebars AND I experienced the wobble right out of the gate, er, crate; pinning this issue on tire wear wouldn't be my top hypothesis.

AGirl

+1 my '06 wobbles and can be felt hands on. Seems to be worse since I put Avon Storms on.

 

[cougar8000]

David,

Not sure if you have found the source of your wobble and clunk. But I definitely found the source of clunk. This past weekend was the first time I was able to ride the bike, you know leaving in Chicago, and there is a sure problem with the steering nut not been tightened as it should be. Sitting on the bike I rock the front and I can hear it and feel it move. This weekend will be putting it apart to tighten things up.

AS far as wobble. No problem here.

I would advise all 07 , at least those that got their bikes from the same batch as me from D&H, to check their steering. Pick up date was around mid January.

 

[Inlaw1]

But I definitely found the source of clunk. Sitting on the bike I rock the front and I can hear it and feel it move.

Maybe yes, maybe no. I've had the same problem, as has three other 06/07 FJR owner I know of. I'll repeat what I posted in post #4 of this thread:

"As to the clunk, it's the linked brakes. One more time: On Yamaha's linked brakes, when you activate the front brake only, three of the four pods for the front brakes are activated. The third one is activated when the rear brake is used. This is the one you hear rattling loose on the pins that hold the pads. If you squeeze the front brake and get someone else to activate the rear brake and rock the bike it won't clunk.

I noticed the same thing when I got my bike and also didn't think it was coming from the brakes. I was wrong.

Wouldn't hurt to check the headset bearing also though, just to be safe. Set the bike on the center stand, have your buddy push down on the rear of the bike bringing the front tire off the ground and grab the forks towards the bottom and try to shake them. If you can move them then it's head bearings."

HTH,

 

[Mortimer]

I'll bet, that sooner or later with the front tire wear every FJR owner will experience some wobble of the bars when letting the bars go upon deceleration.

Sorry if I didn't make my post clear, but my wobble is felt w/o even letting go of the handlebars AND I experienced the wobble right out of the gate, er, crate; pinning this issue on tire wear wouldn't be my top hypothesis.

AGirl

+1 my '06 wobbles and can be felt hands on. Seems to be worse since I put Avon Storms on.

Did the Avon have deep tread grooves?

I just replaced the factory metzeler mez4's on my 03. Yea that's right, first new tires ever. Shinko 006 on rear and 005 on front. I didn't want to mix the tread pattern but need dictates decisions, not desire. Put the rear on about 2 weeks before the front. Overall performance gain was marginal with the new back tire. It didn't make a big difference, but it didn't degrade performance any. I guess what the dealer told rock about different tread patterns might have been on the spot bullshit. When I replaced the front tire though the entire game changed. Before the shinko front tire she never had a shake, even with a very worn front tire she was a smooth as snot. Now I gotta decel shake at 59-42 mph, but only when I let the engine drag brake her, not when I use the brake. I also have noticed that through about 12-3 mph while braking to a smooth stop I get a weird feeling, kinda lika a baby wobble but not really. It's like when you drive over those patches on the shoulder of the expressway, more of a rumble.

Another thing I noticed the front tire changed was the handling performance was drastically increased. I almost ran off the rode when I first got on her and it was about a week before I got used to it. The first corner I leaned into was almost my last. Felt like we were going to fall over. She had me leaning early for every turn and backing out to late at the other side. This is due to the shinko having a "rounder" tread profile.

somewhere, somebody posted about the center grooves being one of the reasons for the wobble and I got to lookin at the pattern on the shinko and, low and behold, that tire has deep tread grooves that cross over the center line of the tire and the next groove going in the other direction. That groove crosses over the next groove and so on. If follow the grooves of the tread with your finger (yea I've been in the garage alone to long) switching grooves at each "intersection", your finger traces out a path like the design on Charlie Brown's shirt, back and forth just like my handlebars do.

it was really bothering me that the shinko caused a shaking while a severely worn out (and I mean worn to embarrassment) rode just fine. well blah, blah, blah, got to lookin at the metzeler website and found a brochure touting that the "MEZ4 stability comes from it having a "flatter" tread profile. I think what is happening is that the tires, for the most part, the install stock are specifically chose to trick us. The special metzelers just for the FJR? what makes them different?

Because the tire I put on the front has a "rounder" profile, and the deep, wide tread in my shinkos is having a larger effect on the front end stability. I think it's also exaggerated by the weight of horses. I talked to one of my professors about this idea and he wanted to make it a resonance case but, why didn't it do it with a badly worn tire. No answer. Trying to get in to see a vibration specialist though.

Let me here from the group if anyone can remember having the stock MEZ4's and the Z6's and tell me what the difference is between the two. And also the difference between the regular and the FJR only Z6's.

Also, the "roundness" I'm talking about is called the "crown radius" (learned that today) and they must kill those numbers when they make the tire mold cause I can't find them anywhere. I sent an email to metzeler asking for dimensions and they replied that they discontinued that model tire and the only specs they had let was the ratio profiles I gave to them. Ha they just disappeared or something.

I'm going to get some tapered bearings and get this shit behind me. It really bothers me though cause she never wobbled before and nobody I talk to seems to be able to come up with a reasonable explanation why.

Here is a link to the tire I got on the front. hopefully you can see the zig-zag design like I do.

Charlie Brown Grooves

 

[Mooseonagoose]

Very minor headshake, but only at slow [30-35mph], decelerating toward a stop w/ hands momentarily off, fully loaded, tires @ 39/41, ...not noticeable w/ even one hand back on the bar. Subsequently played w/ it a bit, seemed to be consistent/predictable when loaded, but can't induce it un-loaded, so I'm inclined to believe it's that I need to dial the suspension in a touch for loaded travel. Also, I know I was over-packed at the time, so maybe I was just carrying too much junk?!

 

[Sir Price]

I have an AUssie 07 delivery that shakes its head on the decell between 80 and 60 kph with hands off the bars , I have OEM tyres and did get the head stem bearing tweaked at 1st service , they did say that the bearings where OK but brought them up a notch.

I do now have acsess to a spanner to adjust them myself which I may do if it gets worse.

At all other speed so far its stable as 1 up or 2 up , fast slow , smooth or bumpy its a freakin awesome machine. Just completed a 400 kolimeter back road ride this last Sunday in howling wind and felt as safe as houses .

 

[stagecoach]

+1

I had the same wobbles and headshake when I bought my 2004 secondhand. When I started to dial in the suspension for my weight/style, it turns out that the previous owner (unknowingly, no offense Bob :huh: ) had set the rebound damping differently left and right. After changing the settings, no wobble or shake whatsoever. Check your suspension set-up first, it's quick and easy!! If that doesn't cure it, move on down the list TWN laid out.

Oy, it's not the nature of the beast. My bike has always - ALWAYS - been dead stable. Worn tires, cupped tires, miss-aligned moon phase and all. In all likelihood, it most probably is related to suspension set-up, failing that, loose steering head bearings or mis-balanced wheels/tires. Improperly inflated tires might do it, too. The design of the bike is solid.

 

[ML-FJR13AE]

Hey Wingman,

Did you ever solve the head shake issue?. I've done almost everything I can and mine is really bad on deaccel AND on accelration...

Martin

 

[dll]

My wobble turned out to be a scalloped front tire. New tire made it feel like a new bike

 

[Wingman]

Hey Wingman,
Did you ever solve the head shake issue?. I've done almost everything I can and mine is really bad on deaccel AND on accelration...

Martin

Check your front tire for irregular wear, and check the torque on the head bearings. Those two things seem to be major contributing factors to headshake. If you find irregular wear on the front tire, odds are the shakes won't go away until you replace it. If you do replace the tire, get a calibrated pressure gage and become religious about keeping the tires fully aired up.

My problem was a combination of mostly front tire feathered (scalloped) wear and very slightly loose head bearings. After tightening the head bearings, as long as I kept the front pressure at 42 psi the shake was really only a shimmy. As the tire pressure dropped, the shake got progressively worse. It has gone away completely after changing the tires to PR2's and keeping them fully aired up.

David

 

[jameswilson]

Hi,

I had exactly the same issue with a 07AE at 300 miles. Took it to the dealer, there first response was I had to live with it. After threatening to document the issue and then let my estate sue them after I crashed they agreed to check the bearings and other issues. They reported that the mechanic took the bike for a ride and decided the tire was out of balance. After attempting to balance the tire they ended up replacing the front tire as defective. No problem since, now at 4,500 miles.

Thanks

Jim

 

[charismaticmegafauna]

I had exactly the same issue with a 07AE at 300 miles. Took it to the dealer, there first response was I had to live with it. After threatening to document the issue and then let my estate sue them after I crashed they agreed to check the bearings and other issues. They reported that the mechanic took the bike for a ride and decided the tire was out of balance. After attempting to balance the tire they ended up replacing the front tire as defective. No problem since, now at 4,500 miles.

Was it a Bridgestone or a Metzeler?

 

[Nateskate]

I had tapered bearings installed today. Six weeks ago I had new tires put on. Noticed a head shake on the way home. I took it back to the dealer who had put the three sets of tires on to get rid of it. It shook mostly from 50 to 40 on decell.

I didn't trust the dealer or his balancer so I took it elsewhere. They re-balanced the front wheel and installed the bearings. They also changed my suspension settings. The head shake is gone but now the bike feels less secure... like the center of gravity has been raised. Did they screw up the suspension or leave the bearings too loose? How can I check the bearing torque? What's the best way to set up the suspension? Also the tech inflated the Storms to 36 and 38. I told him the bike called for more but it was his opinion to under-inflate. What say you?

 

[03HiYoSilver]

Nate,

Here is a nice discussion regarding this subject:

https://www.fjrforum.com/forum//index.php?s...120484&st=0

 

[jameswilson]

I had exactly the same issue with a 07AE at 300 miles. Took it to the dealer, there first response was I had to live with it. After threatening to document the issue and then let my estate sue them after I crashed they agreed to check the bearings and other issues. They reported that the mechanic took the bike for a ride and decided the tire was out of balance. After attempting to balance the tire they ended up replacing the front tire as defective. No problem since, now at 4,500 miles.

Was it a Bridgestone or a Metzeler?

Factrory tire and replacement were / are both Bridgestone.

 

[Anthony]

A longer wheel base should make for a more stable ride at steady speeds, but make turn-in slower. I'm not sure that a longer swing arm implies more or less stability during decel.

Not exactly true. If the suspension is the same, then a longer swingarm will cause the rear of the bike to be lower if overloaded and higher if underloaded. This is a simple equation of leverage ratios, although I doubt the swingarm length difference is of any significant value (+/- at least 10% would most likely be needed to alter this). Here is a geometry primer: https://www.sportrider.com/tech/146_0310_art/index.html

There are several other factors that can alter wobbles, even down to obscure issues, such as improperly damped straight rate springs that have the potential to set up harmonic oscillations. This all changes when you change your weight, weight distribution, tire pressure, riding position, windshield angle, windshield height, etc.

Not trying to argue, just trying to clear up confusion.