I had a great ride going. CA Hwy 126 is a dinomite road. I was coming home from the AMA races at Infineon Raceway, which is about 200 miles from my home, the back way.
Anyway I hit the flats in the valley and upped the pace quite a bit on the long straight flat roads. I engaged my new Throttlemeister and relaxed my arms......Whoops....thr front fork started shaking. Kinda like about to start a tankslapper, but it stayed constant and didn't accelerate.
- I turned the steering damper full up but it didn't stop the shaking! (Bad damper?)
- My front tire, Dunlop Qualifier, has 600 miles on it. It's wearing more on the outside of the grooves than on the inside by maybe 1/64". Could the tire be mounted in the wrong direction?
- 36psi cold air pressure....Too low?

Mine does that as well. So i just don't let go of the bars.

It should have arrows molded into the sidewall pointing forward(as with the arrow/tire being at the top of it's rotation("O" degrees)).42 psi I'd go with.No clue on yer damper.Sure she's balanced okay?My guy always puts weights on my wheels.Sometimes they work good,other times...I've had to remove them on the side of the road-the front was vibrating above 100 quite a bit.Was smooth as silk after that.Qualifiers are new Dunlops(new style?)....maybe something there?

Slow...you can't pose "comfortably" with yer hands on yer thighs going down the road if yer frontend's shakin and bakin!Geez.

Could the tire be mounted in the wrong direction?

Naaaaa. Even if it was, it's the internal folding with an inner and outer layer, that has vulcanizing written all over it? I doubt you will pull that fiber away from that fold over, well before you wear out the tire in another 3 thousand miles. So really, the direction does not matter in a wobble type condition. Let's narrow this down:

1. Yes, the tires were change as a set*** = Both have even rolling wear, though one wears different than the other, obviously.
2. No, the tires were change as the rear was still looking good so I just changed* the front* with 600 *miles on the front right now.
3. 36 PSI is a solid variable with a soft wiggly front carcass. 42psi up and re-ride the same input you made to shake the suspension up. No, the steering neck shock, should be turned down and as ride-able for the slowest of moves; You want that psi to talk quick on the lightest hand gesture. Once that variable clears, meaning, it still wobbles, then you begin to keep clearing what questions I keep compiling for you;
4. Yes, I use the same profile matching tires.
5. No, I could not pass up the deal on this tire, so both mismatch as we speak.

You hear about this arc on the road for rain being that roll-pitch? How come when they lay asphalt, they use a flat rolling pin kind of vehicle to lay the tarmac down? Are you banked over to the left or right that much on the road to make that kind of arc on one side of your tire? Do I believe that? I go to my car tires, I see the edges gone because I throw it in the corners and it's on that edge of the wrinkle, yeah. Other than that, there is a lot more wide to arch around the road having a car tire in place, how come that profile is flat across the wider tire? How come your tire is rolling over when that flat rolling pin was smashing down flat, a hot goo? Show me the arch of the triumph rolling pin is pizza has an arc too, right?

So, inside the rim, look through the disc, look for the arrow direction for the rim to clear that rolling off center to the fork.

Sharkey, This is typical game of chassis setup or we are in a tuning setup, I ask BAD to choose a number so we can continue the tune. I'm trying to weed out the stereotypical wobble, choose a number or pick the best combination of numbers. I see a wobble in the making. There can be so many variables with new, used, half this with half that is just walk this; as one chess move at a time. What is your tire setup? Time on both tires? And without more info on your end, look how raw BAD's rear end is looking right about now. Those were just a few saddle up questions going in here.

Waiting for a number(s) game from you now, Sharkey. Think I'll go an start up the BADBQ with a post toast teas, just to see if he picked a number yet or is still picking his... _______________ Fill in the blank.

This is your Qualifier.Okay...you say the treads are worn where?On which chevron(middle or side ones or both) and on which side of the worn chevron?(Leading edge,or trailing edge)It sounds like you've been hitting your brakes(front)aggressively in turns or coming to an "unstraight" stop.By aggressively,I don't mean HARD in the turns...but using the front to adjust speed while leaned over,OR entering the turn applying the brake to slow up some.Am I warm?Your Qualifier is classed as a what...."hard".soft,or both type rubber tread?And it was unnoticeable UNTIL you were on your way back?And the temps were?And you were hitting some curves at high speed?Just guessing here.Do they appear CUPPED?It sounds like they are with your wear description.Even at 600 miles...they could cup easily under the right conditions.Hard brake application for one....they do say...."no hard braking for the first 100 miles",yes?Sorry Sharkey...don't mean to sound like a friggin lawyer!!!!!You can get that kind of wear by hitting curves VERY FAST as well,and your front tire is slipping VERY slightly(unnoticeable actually)(until she breaks loose)!!!WoHaaa.....steering damper PROBABLY won't save ya with THAT one!But maybe?

* Last updated by: blue07 on 5/21/2010 @ 2:21 PM *

Why is so necessary to add a steering damper. I suppose if the manufacture thought that the bike needed a steering damper, they would have installed one from the factory. I would assume because the steering geomitry is not as steep as let's say a zx10, the zx-14 is more stable but slow steering. My thought on adding a steering damper to the zx-14 is hurting the bike. I would assume the their is a synergy between the motorcycle, frame, suspension and tires that allows some flexing and forgiveness that equates to steering input and chasis flex, hence head shake.
Opinion???

Well...I'm inclined to agree Ride.Kawi's not stupid.They WOULD have put one on if needed.The ten's got one,yes?But it's 100 lbs lighter,and rides differently.However...I DON'T think headshake is an "acceptable" situation for a 14.I think the designers built it to NOT have any headshake.Mine doesn't,under ANY circumstances(except for a worn tire or something along those lines).In fact,I've yet to hear about a 14 tankslapping.My 12,yes,it did tankslap at 70 one time.But the rake is a bit steeper on that bike than ours.AND,the front Dunlop(stocker)was hard as a rock.AND....the asphalt was like 35 degrees.AND....I was powering out of a curve passing a Semi(bet he laughed is arse off on THAT one!!!!) I wasn't laughing...that's fer sure.

* Last updated by: blue07 on 5/21/2010 @ 3:16 PM *

The 14 will headshake- just try hard enough, with or without a damper.

42 psi cold is way too much IMHO, 36-38 here.

If dry, I reverse direction of the rear tire on my track bike during lunch break at NJMP in
an attempt to keep the wear somewhat even and top out 6th gear with zero issues, few seasons now
and on Michelins, Pirellis, Contis, Bridgestones etc.

* Last updated by: masszx14 on 5/21/2010 @ 9:05 PM *

Try hard enough? How the heck do you "try" to get headshake?No matter what I do-fast,slow,accelerate,slow down,hard corner...whatever....I can't GET mine to headshake.EVER.Tankslapper...that's ALWAYS possible,without much work on some bikes-but that isn't headshake.Slight lofting coming out of corners with the attendant wiggle is not headshake.It's uneven rider force on the bars.The frontend will track straight if ya let it.BTW....Hi Mass!Glad yer still among the riding!!!I've "tried" to get er to wiggle.No go.Push yer bars back and forth REALLY FAST.It's virtually impossible to create an unstable situation at any driving speed.The front wheel won't allow it.UNLESS yer strong enough to just REALLY crank the bars.Then you get what you are asking for!Wiggle the bars..either one....let go.It will stop any movement side to side the second you remove the force.If yer front tire is skipping the pavement...ya....it will track in the new direction UNTIL it contacts the road firmly.And if the wheel is turned at just the right amount with no way to self correct when it contacts again,bye-bye.The geometry of our 14's is very good.They knew what they were doing all things considered.

* Last updated by: blue07 on 5/24/2010 @ 12:55 AM *

The 14 will headshake- just try hard enough, with or without a damper.

My hands hardly touch the bike it seems. If I hit a bump @ 80mph just staying with traffic, the front end takes off. I let it settle down without grabbing tight to stop it as if I can control that kind of force. Once it moves straight back in line, you think nothing of it.

I'm with you, pastu; Pass on destroying the input you hardly have to touch the bike to move it.

I will say...if yer frontend suspension isn't set for YOU....and the kind of riding you are pushing your bike to handle,then,ya,road irregularities and such can begin headshakes and slappers.But the bike is designed(at least MINE was)to be adjustable to stop that very thing.And she does...without a damper.She handles much more predictably for me with the correct book tire pressures and suspension settings.(the factory settings were NOT okay for my style and weight).Once I started checking my tire pressure faithfully and keeping it at 42/42,(cold)-she's been way better at turning in and such.Even the straights and all are more planted.Like you Hub...I use VERY light inputs on my bars...and everytime I feel tightened up at the bars(gripping,pushing)I feel the bike get less responsive.As soon as I focus again on easing up and lettin the bike stabilize itself,she does much better.In turns,I can just "dampen" if you will the bar I want to use to make the turn,without grabbing it in a deathlock.But even at higher speed turns,and rough surfaces,she doesn't try to get sideways.If she jumps a crack or somethin in the road,the forks don't squirm around...VERY RARELY...if at all.So minor I barely notice it.I've had er jump leaned over and the front wheel was off the pavement for at least several feet's distance.She still didn't wiggle.Or change track.The wheel stayed right on the money.At over a hundred.I've got complete confidence in my baby.Kawi got these birds right IMO.

* Last updated by: blue07 on 5/21/2010 @ 10:02 PM *

Mass might run warmers. By the time the bike is running track heat, that pressure might be in the 40's hot. 42cold is ice skate ready. And how much do you need if a skate blade is thin, quick turning? All the air you can throw in the front. Now we are talking. One slip up and down you go. Knife edge = Racer's Edge!

No shakes here. No wiggle with my hands off the bars. The steering snaps right back to center when the tire catches touches the road after a moment of lift.

I think Sharky is talking about a constant shake in the handle bars, not some kind of ballistic motion caused by wheelies or bumps in the road. That sort of head shake i have been hearing about for over 2 years but never a tank slapper. Some people have it others don't. Brake usage always gets mentioned. If you brake hard the front tire wares in a weird pattern and this can cause a shake if the rider's arms are not stablizing the steering.

* Last updated by: Rook on 5/21/2010 @ 10:21 PM *

Ya Rook...that's what he's talkin about.I had that as well....new tire solved it,along with some modification to when and how I apply front brake.

I run 42 in the winter and 40 in the summer. never had any prob with headshake.

I did run at 38 for a while, but found that with my weight on the bike I scalloped the front tyre pretty badly.....

I have never had the bike shake its head on me......

Is the front end any lower than stock ? I read on aonther thread that someone lowered the front end of their bike to 'increase turn in', maybe this would affect the straight line stability as well.

I agree with hub, I always run tyres that are a matched set. People a lot brighter than most of us engineer the buggers to work together as a matched set. It makes sense to me 95% of road riders should use them the way they are designed. (IMHO)

OZ

* Last updated by: ozjohnno on 5/22/2010 @ 2:44 AM *

I'm listening to some riders opinions. Funny topic, like learning to ride 1 on 1. As what blue stated, when you start adjusting the bikes suspension to YOUR weight and riding style. ANY motorcycle will feel like a different bike from what you first started from. MOST of you will agree, when you are one with your bike you don't have to think about pushing bars leaning or any rediculious novice moves. I actually found that my skill level went up a ton by reading motorcycle racing books. I employed some techniques on the street. Let's say a piece of debris right smack infront of you in the road. Some would counter steer, but that makes the steering arc pronounced. Try steering with leaning on the pegs. Go right, push down on the right peg.
So much involved in riding safe. But isnt it funny, riding safe means riding fast.

If you come down hard from a power wheelie, lets say at the top of 2nd gear or even at higher speeds
or if you get on the throttle hard early while still leaned (the 14 easily has the kind of torque for that),
the bike might develop a headshake.
BTW my forks are revalved and resprung by GMD and my wheels are really light,
this still isn't a platform that will overcome any abrupt or wrong rider input.

Sharkey, you might just have a bad front tire. Happens somewhat rare but even a brand new set might
just feel "bad" at that certain speed.

* Last updated by: masszx14 on 5/22/2010 @ 4:37 PM *

Yea, it was a constant wobble. I had a ZX12 once that would go into an evil headshake when I hit a bump. But it took something to initiate it.
Anyway, I fixed it. What did I do? I worked on everything, except tires which would have been a last resort. I raised the tire pressure to 42psi, tightened the clip ons and check the mainstem nut. I set the preload 1 click looser, and I remounted the steering damper after bench testing it. When I got done I had only the teensiest tiny little bit of headshake. And that could have been the rough road.
I don't accept the "that's the nature of the beast" stuff. You should be able to tune the suspension to your riding style. I brake hard coming to a turn and turn a little late. (That's why I made the preload a little stiffer originally.)
I think it was Hub who put a video on showing a guy get a tankslapper followed by a highside. You can't ride for as many years as I do without doing a highside, once or twice, or 10x. But I usually do something to cause it. This guy was on a track, in total control, and either hit a bump or something, and the bike suddenly needed an exorcism!!
It got me thinking enough enough to consider a steering damper. But...why put on a steering damper?.......
They just look so damn cool...

+1 on the coolness of an Ohlins oil cylinder steering damper but OOOOOO are they expensive for the 14.

Hey Ridepastu....okay...I tried the peg loading to see if I could get my baby to actually "turn" at forward speed.No dice.She leaned,but the wheel tracked straight.Only by countersteering did I actually get a swerve deal going.It's all good.I've tried avoiding things(like sharp looking small rocks)by leaning the bike over to either side.Invariably I hit the rock or catch it just barely.The almost imperceptible input of"steer right,go right"(or left)is so far the only thing that allows me to "steer around" anything ahead.This could also be an unconscious movement while looking away from what I'm trying to avoid....looking where I want to go instead of at what I want to miss.My bike won't "turn"/swerve" without input to the bars.I've tried...numerous times.And Sharkey....I'm thinkin that tire pressure actually has more to do with the behavior of the frontend(and unusual tire wear) than is given credit for.I'm keeping mine at 42 cold.I'll tell ya...she feels a tad different than 38,39 or so since I've been doing this(for about a month now).Better feel...better turn in.Better tracking in the curves.

* Last updated by: blue07 on 5/24/2010 @ 12:51 AM *

You are right, blue. Can't peg a change without bar input. You can't steer a bike with a peg or a solid steering neck that points forward and that is it. You gonna move that bike with a foot peg now? YOu think you can move that handle bar with only body-english, I have an english castle for you to buy along with that bridge in N.Y. It's a very nice cardboard box from a refrigerator. We can draw the plank over the sidewalk curb. You are a king in your own....

LOL, I'm laughing. Please don't misinterpret what I said. NO you don't just steer by leaning on the pegs. But by a quick push on the pegs the bike will turn. Look, ask experienced riders and see what they say. Also (HUB) most inexperienced street riders, (wanna-be sport pilots) are doing too much at the handle bars and not enough with the overall bike, i.e. leaning, foot placement, body positioning.
HUB, don't be a jerk.

LOL, I'm laughing.
HUB, don't be a jerk.

I stop being a jerk, you are no longer going to laugh.

Stand on your pegs. Which would be easier to control as if you were rolling too, but you are just at a dead stop on the garage floor. Have the bars locked or let them swing back and forth, you have more balance and control with the hinge at the front, right?

Would you have that pitch at the peg a lot steeper with the hinge working or just plop over it now is just a plank of wood with foot pegs off the side. DON'T BAD ME... Yes or no, can you move with a hinged bike or with a handle bar moving back and forth, you are more stable with that bar poking the peg.

Yes or No?

Well...I find the input to the bars is the "only"(if you could call it that)way to angle the front wheel off center...to get yer bike to fall either way to initiate the turn.HOWEVER,Ride is also right about the "other"inputs as well.body positioning and all that.HOWEVER-THOSE inputs are NOT making it possible for the bars to cause the bike to fall into the turn.That initial force has to come by offsetting the bars...subtle as it may be at times.That's my understanding of it.As I said...when I pushed on the peg...granted,there was a SMALL movement at the steering head...yes...but NOTHING like could be called "turning".It did not "swerve" well at all.The whole bike leaned,but the track stayed straight forward.I'll give er another try,see what she does.

* Last updated by: blue07 on 5/24/2010 @ 1:04 PM *