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YAMAHA FZ1
Headshake 

Through the first season of 8+k miles on the FZ, I do not have headshake, all the way up to about 150  (240 kmph) actual speed (near 165 speedo), however headshake has been reported by a few FZ owners.  It would appear however for the average high speed rider, there are no headshake issues with the FZ.

If you surf into this page and have some information or experience to add, 
please post to me.  Headshake is a very real and serious issue!!

Headshake is usually felt first up top, at the bars,
but it starts down at the fork area and resonates oscillation forces throughout the bike.
Headshake is extremely dangerous at high speeds if it is severe.
Extreme headshake feels like the bike is going to tear itself apart and crash, and it can.


Try this,  to role model a stock Vmax at 130-150 mph heading into St. Vitas Dance, a killer disease-----

.....The physics of headshake is very complex but basically a combination of mechanical factors come together to start lateral or sideways movement of the bike, generally starting in the front  end from the headset down, but then transferring through the entire bike and rider.
.....Right now stand up and bend you knees a little, put your hands out in front of you at handle bar width and shake them sideways, back and forth,  just as hard as you possibly can, and keep it up.  Let the shake go all the way up into your shoulders letting them get involved with the violent movement of muscle tension.  Let the shaking movements get really big to the point you have a hard time focusing your eyes on anything, while at the same time let your hips and whole body start to get involved in the shaking. You are now on a Max in trouble and have to get out of it.  But before you do that, close your eyes and lift one foot off the ground at the same time, and shake even harder.  Once a Max goes through headshake on the way up in speed, it will often get more violent when coming back down.    
.....The oscillations of a bike in headshake will have different frequencies and different intensities depending on the speeds and how long they are allowed to go on.  
.....Big low frequency movements are the worst.  They are not the "buzzy" type of shake, but create a big violent and dangerous "wobble" that can cause total loss of control or breakage of the bike, ending in a severe crash at high speed.
.....Does headshake cause many accidents??  Probably very few, as most people will back off before getting too far into it.  But, yes headshake has and will cause high speed crashes.  One of the best examples would be a Vmax dragging with a Bandit, where one is concentrating on shifts, road, etc. and "forgets" the shake building up as the speed just explodes taking the bike into headshake very rapidly and violently.  Hard, fast acceleration to high speed can catch a rider by surprise.  Also a rider who has a mind set of running his bike to 130-150 will be focused on the speed goal and let headshake get away from him.  I have literally endless tales of severe headshake with my  dinosaur muscle bikes.  If it can happen, it will happen, be careful of headshake.

Is my FZ going to have headshake?

.....Most bikes do at very high speeds, so I was expecting something, plus I am more than paranoid after years of fighting the Max and Mag.  Someone with a lot of sportbike experience can give their impressions from that standpoint.
.....I am not getting headshake up to 150mph.   I have been running hard on the highway and had many passing runs to 130+.
....I am running firm tires, 36/39lb. and fairly firm to firm suspension adjustments.  
....I am running with a Givi screen and a Memphis Shades Demon shield on the bars, with no indication of wind problems setting up oscillations. 
....NOTE:  A  Sigma bicycle computer indicates  that the 150 stock speedo reading is about a 134-135 actual, and that the top speed of the FZ1 is 154-155, the same value that the calculated speed has been reported.   I have not pegged the FZ out and probably will never run it as hard as the first summer, so cannot comment much farther on top end street speed, nor headshake at redline in sixth.

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One bike that can do it all for me? Yes

 

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Yamaha FZ1
Headshake
Does it or doesn't it??

 

 

 


Does the FZ have the "Shakes?"
.At this early date in the history of the FZ in the US it would appear that headshake may be an issue.

Do I have the "Shakes?"
..Certainly do!!! On the V65 and Vmax. I am the Shakemeister!  Even though mods have created a much better suspension on the V65 and Vmax, they will still do their "thing" at time and rarely can be run to top end high speed, like the FZ.

What about the FZ?
..I have not experienced the shake or wobble with my FZ, yet!!!  

Have I tried to get the shakes with the FZ?
.Oh yeah!! Once a 'speedaholic', always one.
.In early June of 2001, I ran my FZ up beyond 130 for the first time. It had about 1600 miles on it by then. I had been running the bike very hard from the beginning with basically no break in period. Its break in was at 70 to 100 mph most of the time, with a lot of runs in the 110-130 range. The FZ has no self-control, but it did not show any indications of the shakes during the first 1600.
.Having lived through the death grip of the shakes many times on the V65 and Vmax, and especially the Vmax, I was expecting the worst when taking the FZ beyond 130. I really did think the bike might be fine up to about 140-145, but still was like a war prisoner, not wanting to go back.
....On a very long straight of about 20 miles, I brought the FZ up twice to 130. No shake. Then a run to 140, solid. Gads, this is not right!! I was coming up on a smaller "sporty" on the next run. A quick look at the speedo indicated 140 and all okay, so I called on the throttle monster a little more and we blew by the midget. No shake, NO wobble, and we were holding speed for about a mile, speedo sitting right on 150.  Absolutely ran straight and true, to my amazement.
.So it would appear that my FZ can run beyond 150 (on the speedo) without any signs of headshake.  At least the first time was successful. This was also with a Givi screen on the cowling and a Hell Cat shield attached to the bars, plus a 12 x 24 inch duffel bungeed across the seat.
.Since that run to 150, I have had a chance to try other high speed series.  I was sure, the Shakemeister could coach some sever wobble out of the FZ, as I was more than successful in turning the Red Max into a Christine.  After installing a Sigma bicycle computer to get some actual speed reading and making some high speed runs to 140-150 actual with no headshake, I am fairly assured the given good tires and normal conditions the FZ is basically "shakeless" for all practical purposes.
..Would someone please build a street bike where the frame/suspension is bigger and "badder"  than the power train, or at least equal!! So it looks like the FZ could be. At least I know it will consistently do 130-150 on the road, which is just about fast enough for all passing.

 

Bearings and Bicycles, applying headshake experience to the motorcycle----

.At one time I was into fast bicycles, racers that could fly down steep Iowa and Wisconsin hills at 45-55 miles per hour and weighed a couple of pounds more than twenty. You have your head into the wind and your body in the most aerodynamic position possible to get the most speed out of every big hill. When you are a speed freak on a bicycle you learn the best tuck from experience. Nobody can tell you a whole lot about the tuck for speed, you have to feel it over and over. You become very sensitized to the environment, the air flow, and especially the feel of the bike. A good racing bike ridden thousands of miles literally becomes an extension of the body. You can sense, feel, relate to every little part. You learn to totally strip your mount down to the individual bearings and to put all the very delicate, but very strong, precision parts back together. All the many working parts of a racing bike are actually in physics what would be called simple machines which must come together to perform the work and create the highest speed possible for the "engine" coupled to it, you. Once a bike is worked on it generally takes quit a number of rides to fine tune everything back to its best racing/speed level. Headshake is most common during this tune up time of the bearing races, or after use and major wear of the bearing or because the bearing race fasteners have become loose.

.Bicycles and motorcycles are very similar machines in many ways. Very high speed in both of them will bring out weaknesses of handling, cornering, accelerating, decelerating, etc.

.Now back to our topic of headshake. When you are in a tuck position on your bicycle, with your butt in the air and your head out over the top of the handlebars, and flying down a hill at 50+ mph, I guarantee you do not want headshake in the front end of the bike. We are talking violent, severe, extreme side to side motions that re-enforce themselves, that result from some set of mechanical issues. Like sound down the right length of a hollow tube such as in church organ, the front end vibrations start to re-enforce each other, becoming bigger and bigger. If you cannot get your speed back down and out of the wobble zone it is a "naked" head first crash. A belly flop and skid on pavement at 50+. The thing about wobble on a bike is, once it starts under gravity acceleration down a hill, it is nearly impossible for a rider to catch it fast enough to back out of the speed , so he/she is well into the wobble zone and coming back out will generally produce even larger wobbles and instability, so that is when crashes often occur.

.I have been in the death grip of high speed wobble on a bike on four different occasions and was very lucky to get out of all of them. I can re-live every single time, the first decades ago. That is how impressive the near death experiences were/are. All felt like you were standing on the edge of a 100ft high bridge and totally out of balance control and knew you were going to falling, but by some unconscious lucky reaction you made the right recovery move and saved your life. You feel weak from the adrenaline rush, scared, lucky to be in one piece. Wondering how you survived without disaster, cautious for awhile. But you are a two wheel speed freak so will run the hills whenever one is in front of you. Point is, better pay close attention to your machine, quit or be forced to quit.

.Folks, bicycle riders know dang well that they cannot afford headshake at high speeds. Motorcycle headshake is a much more complicated issue because of the bigger variety of factors, the weight and size of the machine, etc. But here is what we know as bicyclists. Take away the engine, any wind protection and other nuts and bolts of the standard motorcycle and you are down to frame parts, wheel parts, bearing parts. It is in incorrect articulation (joining) of these parts with one another in a high speed bicycle that will allow them to move or vibrate upon one another and set up oscillations or headshake which will then be transmitted throughout the bike and rider. The degree and intensity of headshake depends on many factors but speed is the primary issue. Faster the speed, the more likely to have severe headshake.

.My experience with headshake on a bicycle points to the way the bearing races and bearing "fit" in the headset and the axels. It is pretty much as simple as that. The bearings. The fasteners that hold the bearings in place must have just the right about of torque or tightness.

.And let me tell you, that is not a science at all. It is generally too complicated for exact measurement. One learns on a bicycle by constant work and repair on the headset and axles to have a "feel" for just how tight they should be.

..My experience would indicate it is a bit better to have the headset and wheel bearing a little on the tight side. It they become a little "sloppy" from wear or incorrect adjustment, then headshake is likely to be the result at very high speeds.

.My personal experience with racing bicycles corresponds almost exactly to what the Vmax'ers are saying. The torque or tightness of the head set bearing and sometimes the wheel bearing are one of the primary issues. The trouble is, with motorcycles the average rider is not going to able too, or if he can, he is not going to strip the front end down and check the health of the bearings and the bearing races, then put everything back together and back together in just the right way to work. Just because the book says "torque to," does not mean that will be the tightness to keep headshake at bay. This is not a science we can understand, unfortunately.

.Perhaps a common sense approach is best. Keep tire pressure firm, check all frame and other fasteners on the cycle that your can. As remember what I said, if there is a problem with headshake on a bicycle, it is probably resulting from loose bearings. Not pitted or scared bearing, but loose bearings joints, there points of attachment with the frame, etc. If all easy things fail to reduce or correct headshake, then checking bearings may be the best next thing to try, starting with the headset bearings. Tight bearing and tight fasteners, and you may live without headshake or at least live through its grip.

Tight Bearings and Tight Fasteners may not matter!!-------
.You cannot win the Derby with a beer wagon horse. No matter what you do to certain types of weak bicycle frames and systems, you cannot run 50+ mph down hills without wobble and instability. The same goes for motorcycles. The Vmax is a high speed suspension lemon. A few do become moderately  high speed functional but most do not, no matter what the level of work/mods. Bikes like the V65 and Vmax have very weak, soft frames. It is like putting a 6'6", 350# really good bicyclist on a Wally World. It is just going to happen. Flex, wobble, headshake is going to occur.

.I do not think the FZ is in this group. Some FZ's may shake at high speed, but I am guessing most will run 130+ without major trouble, with many going to 150. I have no idea at this time what the general limit of the FZ is, but would also be very surprised if the suspension and frame can take the top speed the engine is capable of producing. The thing the FZ has going is a stiff big tube steel frame, radials, relatively light weight and a pretty good suspension. Also the front end is not "raked" out and appears to be relatively strong. Now, remember I am talking as the Shakemeister of the V65 and Vmax, and someone coming off years on modern sport bikes will have much different experiences and impressions.

.My FZ runs 150 as if on a rail. No shakes, or signs of shakes as of yet. We shall see. One thing I am sure of, with this bike 130-140 can be an everyday thing without even breathing hard or being a little off balance.


 

FZ recommedations regarding headshake for the average street rider
....First of all, test for head shake carefully and see if you have it with your present set up.  Gradually increase speed, if shake seems to be present just let the bike come back down, then retest to confirm when shake starts. Monitor the wind as a cross wind can cause the shakes, and so can a road surface.  And bikes coming hard out of corners can shake, but this is a bit of a different issue than we are discussing.  We are worried about straight line shaking at high speeds right now.
....If you are getting  into the shakes, check the tire for the correct pressures.  Try running firm at about 36/39 and/or play a little with tire pressures.  
....Try to firm up the suspension a little at a time.
....Check the alignment of the back wheel as when you adjust the chain.
....Oh yes, and maybe the most important initial advice. As a rider, do not be the initiator of the problem by having a death grip on the bars or no grip on the bars.  Be somewhere between, with light athletic control of the bars and machine.
....If you are still getting the shakes and it is severe you are looking at doing/playing with some of the mods that the Vmax group has to do, and it is generally a big mystery  as to just what will work/help and when/how.  You are looking at different fork springs, different shock, a stronger fork brace, playing with the torque on the headset bearings, lowering the front in the triple tree, doing a more sophisticated alignment check, trying different tires, and anything else you can dream up.  And looking at my experience with the Vmax, a little change can cause even worse shank that requires even bigger changes.
....I am really guessing most FZ's are going to run straight line up to 140 or so without a hint of the shakes.  But I would like to post your experiences, shake or no shake.  iowaz@swbell.net 

 


 

Headshake to the Max----and is there a Fix-----
..NO, I cannot tell you about the fix for headshake. I can just tell you all about riding cycles with extremely severe head shake issues. I can tell you about being at the "out limits" of stability literally dozens of times while at high speed aboard Honda's better idea, the V65 Magna, and Yamaha's even better idea, the Vmax.
...Have you ever seen a monster black bass come up out of the water when hooked and try to shake the lure out of her mouth. Have you been to a rodeo and seen the power of a Brahma bull violently trying to throw the guy into oblivion. Did your dad ever grab you for being the little devil you are and try to shake the teeth out of your head, to the point you could not see to focus on anything with your eyes. That pretty well describes a trip on a V65 or Vmax without mods, usually happening somewhere above 120-130, but it can happen at much lower speeds, say 80-95. 
..I absolutely do not have the words to describe how severe headshake can be on a cycle. You have to live through some episodes to know it is not for the faint of heart.  It can be so severe as to cause a major crash at high speeds. It can be so severe as to cause a frame or mount to crack. And the thing is, once you have gone up through the "hyper" zone, it is not always easy to get back out of the time warp. Many times you have entered severe head shake and have the speed climbing but as you come back down trying to get control, the shake or oscillations build up even worse than the climb up to speed, where total lose of control occurs causing a crash. And folks this is not at 20 mph, it is at 90, it is at 120, it is at 140 and beyond. I had a sparrow fly into my nose and mouth area from the side, while I was cruising behind a car at 20. He/she hit me from the side under his/her own power and I thought my nose was broken and lip crushed. Headshake is a big issue at high speed.
.The Vmax group continues to strive for solutions to the headshake issue. I am guessing the King of Muscle Bikes is the King of the Shakes. What have we found out that works. Nothing. Or should I say there seems to be no easy magical solution.  There are things one can do to help but the FZ already has many of them. You probably already know that headshake can be created or minimized by issues stemming around cross-winds, tires, frame, weight distribution, fork, suspension, fasteners, rider, and the list goes on and on.
..I could generally run my V65 to 130 before signs of shake and have taken it beyond 140 and to 150 at the top.  The front end of the 65 is too "soft" so I stiffened it with dual rate springs, now it pogo's at around 85 and continues to not wobble but hop a little at higher speeds. It is too stiff to take to the extreme right now. So you see mods to "fix" things can complicate the solutions and create even more issues.
..And then there is Max. Would run 145-150 out of the box for me, stock. Have no idea top of speed. Never did redline it. I could tell shake was an issue, as at times the Max would start its jive around from 130-140 depending on the day or just how he felt. Well, being a good coach and wanting to do things right, I proceeded to do the "fix" on the headset. Which is replacing the rubber washer in the top of the headset with a metal one to stiffen the front end. All Maxer's know that is the magical grail for headshake. I did the fix and my life flashed before my eyes three times before figuring out the doctor had given the wrong medicine to Max. Three times on as many evenings I brought the bike up to 90 and instant violent wobble set in. I cannot describe in writing how violent the wobble was.  By 115 I was in danger of total loss of control. We are not talking headshake here, we are talking violent wobble. Big low frequency wobble, like a bull elephant trumpeting and stomping.
.Point is, just one little bitty change can cause disaster. The Max front end had become stiffer with the loss of the rubber washer allowing oscillation forces to increase, and re-enforce the next wave of wobble so the size or amplitude become longer and stronger. My life was in danger, the Max needed more "fixes" or I could buy a Hardley. So being a ignorant "shade bush" mechanic we started on many more mods in an attempt to correct just one little washer change. A fork brace, frame braces, custom shocks, custom fork springs, lowering forks in the triple tree, new tires, and the list went on.   Wow, what a ride and cornering improvement. Made Max a street performer, but did it take the wobble out. It did help however. Now we see wobble at 125-130, and even if there is no wobble, I cannot trust it above 130 :(  There are more sophisticated solutions to try, all requiring money and expertise with no guarantee and generally only marginal success.  So the solution was to get an FZ and retire the Max to just looking "Bad."  Well, not quite, the Max will still run just fine on the street light to light, and do highway roll-ons, below 130 ;)

Post Script on Mr. Max----- 
....I can mouth the Kind of Muscle bikes, I ride one :))  But you had better not!! You know how that goes ;)
....What is the point of the Max Tale? Headshake and/or wobble are dangerous and very, very hard to correct in many or perhaps most cases.
....There are many Max wrenches that have absolutely no headshake problems to top end, and many Maxes have been modified into absolutely awesome machines.  Max stock is still a street force, especially considering the age of the "living legend."  I am just have a chip on my shoulder that Yamaha did not bring Max up to potential with the engine level.  But the King still lives----
...."Cruiser", Feb 2002, buyers guide:  "If this talk of torquey big twins, even hopped up ones, is putting you to sleep, here's a kick in the ass.  with its hot-rodded liquid-cooled v-4 engine, the V-max, which dates back to 1985, fits the still-crazy-after-all-these-years category. where v-twin fans talk in awe of 100 horsepower and quarter mile times in the low 13's, Mr. Max pumps out close to 140 ponies and turns quarters in the 10's.  the 1198cc, 16 valve, dohc, 70 degree v-4 benefits from an intake trick called v-boost, where crossover tube connecting adjoining intakes on the four carb manifold opens up to double the acreage the engine has to draw mixture through. five speeds, shaft drive, triple disc brakes, adjustable suspension and an under-seat fuel tank round out the package."

A Vmax Headshake success story and solution,  (a simple fix by controlling front end supension sag)----
by TC, one of the most knowledgeable and experienced Vmax riders and wrenches on the list:
....I am responding to your request for input not because I have an FZ but because I have a Vmax (used as an example in your text). I wanted to related my experience with headshake on my Max as I feel it is relatively generic and may be of value. I realize that in most cases the solution is not as simple as it has been for me (so far).  I purchased a new Vmax in '93 while living in Denver, Colorado. I have always had more than one bike and for many reasons .. the Max just didn't get as much usage as I would have liked it to in it's early life. I did take it to the track many times during the first few years but my highway experience with the bike never seemed to exceed 115-120 mph. A few years later I moved to Phoenix and started using the bike a lot more .. and this introduced me to my first real tank slapper.
....Somehow .. I managed to end up going down a long exit ramp next to "some" green sport bike ... and by the time we merged onto the main highway we were into the 120 range. Shortly thereafter the bike started oscillating wildly with the oscillations rapidly increasing in
frequency ... in the corner of my eye I noticed we were just past 130mph (per my speedometer). Needless to say ... I was scared to death... I laid down on the tank cover and pulled in the clutch ... and let the bike float down ... It came out of the slapper just fine. This really bothered me (obviously) so I tried this again on an open stretch of road and found I could continually enter the "slapper" threshold between 120-130 mph. At the same time I noticed that I could "nurse" the situation if I was very smooth with the throttle ... as any quick release would make the bike feel like it was moving up and down and flexing in the middle. It felt like the engine and myself were bending the chassis.
....Ultimately .. I managed to stumble on to a sportbike site and started reading about suspension tuning. I read about static sag .. rider sag.. etc etc ... This was something I always thought would be of interest only to track racers. When I initially checked the bike it had 2 3/8 inches of rider sag (front suspension compression w/ me sitting on the bike). Since the suspension was still stock .. I checked and found only 2 lbs of air in the front forks. At 7 lbs .. the suspension sag measurement came into spec (1 3/4 inches ... 1/3 of the total front suspension travel .... and with the bike only ... I got 1 1/4 inches .. which matched the target measurements described in the suspension tuning article).....Maintaining these sag measurements eliminates any sign of the oscillations ... (at least up into the mid 140s .. as fast as I havegone). Depending on air to accomplish this is of course not the best solution ... cutting spacers to the proper length is much better ... as air eventually goes away. I have found if I ignore the maintenance of the sag adjustment .. the bike will slowly get loose enough thatthe slapper threshold will re-appear in the 130+ range and start working it's way down ... (but promptly disappears w/ the proper sag adjustment is restored).



Posts Regarding Head Shake with the FZ1 (I would like to post any of your experiences/ideas/observations/solutions with FZ headshake, iowaz@swbell.net )
Headshake thread can be found at
http://pub29.ezboard.com/ffz1ownersassociationfrm26.showMessage?topicID=83.topic 

 .....I have noticed that about 130 or so there is a bit of a 'wobble' in the bars.

.....Hit 135 once with no noticeable shake, it was very stable.

....Took mine up to about 130 for a short spurt, and the only shake I had been from my Jacket. After taking the jacket off, and a retry of the same speed, Rock solid.. Have you adjusted your suspension any or left it at the stock settings? Just a thought. I did adjust the suspension a little from stock...

....Wheel balance, at those speeds, is critical; check that you haven't thrown a weight. Also, remember the tighter the grip on the bars, the more movement is transmitted to the rider..

 ....Tire air pressure and steering head bearing torque could also be a contributor. I've also experienced road surfaces and slight cross winds that has caused head shake.

 ....I'm getting the headshake coming out of corners hard on the throttle and also accelerating through long sweepers. Spoke to the local Yamaha guy and he checked the front wheel and said that it looks as though the front wheel is not working hard enough because there is not enough weight over the front wheel. He has a demo on the floor and this week he will drop the front forks about 8mm putting more weight over the front wheel. Then he'll take it for a hard run and see how it goes. You will loose a small bit of clearance but should make the front wheel work harder. The sit up position puts your weight back on the bike and he has suggested having only about 10-15cm sag at the back as well. I'll let you know if it makes any improvement. There is also a national bike meet on this weekend nearby and the guy who has been racing a FZ1 for the last 3 months will be there. I am going to try to see his bike and get a bit more of an idea of how he has the suspension setup as he races in a class where you must remain pretty close to stock in most components of the bike. I'm not looking for a race setup but want a firm setup as most of my riding is up in the hills nearby.

....Before the tranny broke, I set the suspension to different to stock settings. The front preload is only showing 1 line on the blue adustment.  The front rebound and compression is 1 click in on each. The rear preload is 1 click firmer than stock and 1 click in on the rebound and compression. The bike felt better, more like a sport bike, which I prefer. The front end did not compress near as much under hard front braking as it did set to the stock settings.

 ....Couple of other thoughts. Dropping the triple down (same as raising the fork tubes) ALSO changes the steering angle. As the crown goes down, quicker steering and less high-speed stability can result. You should also check your front to rear tire alignment. Most bikes AREN'T aligned (Tire front and back on the same line) even though the rear axle/chain adjusters are set identical. Another bike I own the adjusters are off 1/2 of an adjustment mark when the tires are in perfect alignment front to back. In contrast when the adjusters are set identical the rear tire is pointing better than an inch off to one side of the front. Haven't checked my FZ yet, but even money says it will be similar.
....You can also change the weight ratio front to back by sliding forward and slightly bending your arms. Many dirt bikers actually slide up onto the back of the tank when going into turns for the same reasons. My YZ's seat actually runs up the back of the tank to within an inch of the filler cap to facilitate this. Being you experience the headshake while accelerating out of turns/sweepers, the front being "light" could well be the problem. If all the other options you try don't cure the problem a steering dampener hopefully will. This same headshake is common on the V-Max. It is mostly believed to be frame and swingarm flex. My best guess is the FZ's problem you are having won't be for the same reasons as the V-max. 

.....What is the proper way to check the alignment?  Response----It's a simple process, normally called the string method. Bike needs to be upright, perfectly straight upright. Center stand on some bikes gets in the way. Tie a string around the rear of the rear tire approximately 5 or 6" up from the bottom, have the knot on the string in the middle of the rear of the rear tire. Run the string toward the front of the bike past the front tire. Tie the front of the string onto a brick,ETC, so that it is again several inches above the ground and can be stretched to take the slIck out of the string. Now do the same on the other side of the bike so that you have two strings along each side of the bike going forward past the front tire. Align the front tire to as straightforward as you can by eyesight. Now with enough tension on the string on one side to take the slack out, slide it away from the bike so that the string is NOT touching the FRONT of the REAR tire. Slowly slide the brick back in toward the bike until the string just barley touches the FRONT of the REAR tire. Do the same on the other side of the bike. You now have two parallel strings straddling the front tire. Again straighten the FRONT tire to be straight forward, this time do so by measuring from the string to the tire, both at the FRONT and BACK of the FRONT tire on one side ONLY. This measurement will be the same if the FRONT tire is now pointed straightforward. If you move the handle bars to better align the front tire, go back and check the string to rear tire alignment it will often change as the bars are turned right or left and the bike moves even the smallest amount. With this Now perfect parallel alignment, Measure from both sides of the bike from string to FRONT tire. If you have perfect alignment front to back tire, the measurement from BOTH the right and left side are the same. If the measurement is greater on the left side (as sitting on the bike) the rear tire is obviously aligned to the left, as in the left rear adjuster at the axle is to far BACK in the axle slot. Adjust the rear axle adjusters accordingly until you get the alignment your looking for.
Some bikers are MORE concerned about chain alignment between the sprockets. My normal preference is tire alignment and unless chain is then WAY out prefer to do as described above. The factory adjuster alignment marks are almost NEVER accurate for REAL front to rear tire alignment.

....I know what you mean regarding the change to steering angle. As I have had no headshake at speed just coming out of corners or going hard around long sweepers I was not too worried. Also know what you mean regarding getting up on the tank on a dirt bike.  Have dropped the triple clamp down 10mm and jacked the back up until I have only 10mm sag and now it is just great for my weight. (80kg) It has really made a lot of difference. On the weekend I spoke at length to the rider of the FZ1 which is being raced here under the wing of Yamaha Australia. He said that the biggest improvement they have made to the suspension was ditching the standard springs, which are 2 stage, and putting in a straight 9kg spring with different weight oil in the front. The original spring is 8kg start and then changes abruptly to 11kg. That's why you can get sharp hits back through the front suspension sometimes. I'll be looking at changing the spring shortly.

....In reference to wheel alignment for a bike. You can use a long straight edge like they use when flattening sand before putting down pavers and it is easier to get right although the old string method works fine.

.Well the string alignment method is a lot better than the stock alignment marks, but it's a pain and nearly requires two people to accomplish. Do yourselves a real favor, and but a Rohm alignment tool from RPM. {ROHM PERFORMANCE MACHINE}. On the FZ, you pop of the plastic cap that covers the hollow swingarm bolt. You then center the hollow part of the swingarm bolt, and the center of the hollow rear axle with this tool. {it's adjustable} When both sides are the same, the rear wheel is exactly straight. I have been using one for 2 years now, and there is nothing better. $89.99 +tx and shipping.

....No shakes at 140mph

....Re. a sportbike....Head shake probably has to do with the harmonics of the bike. When you run a more triangular tire (D204, D207) it makes the bike shake. When you run a rounder profile tire (MEZs, D202) the bike is stable. I don't think it has to do with the head bearing at all but just the way that the bike was designed and the way it responds to tire profile."

....I have had no shakes at 140 as well...though I am noticing some low speed instability that wasn't there before...when in the city (<60mph)...going to check the pressure and have the boys at the dealership check the torque on the front end to make sure nothing is loose. I do a lot of highway riding so I don't think tire balance is an issue or I'd have noticed I'm sure. I have to wonder if my suspension setup is responsible for any shakes I may have. I'm using the 'middle' values from the manual except my rear spring is a bit tighter...they could be completely wrong for me. I have talked to some guys I know that race (I figured if anybody knew about suspension setup, a racer would) and they all say they won't tough those tweaks with a 10 foot pole...they pay other people to do it for them.


Posts regarding headshake:

10/2001....My FZ1 definitely does the headshake when decelerating from 50 to 40 with no hands on the bars.  If I TOUCH the handlebar while decelerating it doesn't do it, but hands off it starts wobbling at about 45 and then at 40 if I don't grab it it's about to throw me off.  I also feel some instability at 125 or so and hard in corners a bit of wobble.  My tires (stock) have 5200 miles on them and plenty of tread left, with no cupping.  I run 42/42.

NOTE:  Late in 2001, I have been busy with other projects and have not completely monitored the FZ posts, but I have not noticed any regarding headshake as 2001 one comes to a close.


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