The " wobble " I keep reading about

[jgalloway]

Mine has seen up to 134 with just me, and 120 with the passenger and SH36 bags a few times, which puts us a little over 400 lbs payload. On an approved course, of course.  I had stock suspension. I never experienced any wobbling. I can only imagine the new shock and forks by matt will yield the same results.

[wessie]

or be very heavy - I weigh around 200lbs and have not had any scary moments 
we haven't had a wobble thread for ages - not sure what has happened. Has the wobble mysteriously disappeared? Was it hyperbole and only seen on 2 bikes but the internet did the rest? Are people learning and tweaking their suspension or checking tyre pressures? Or perhaps skinny people are too frightened to buy the bike and only fat people are getting them now? 

200 isn't very heavy. They called me beanpole when I weighed 200.

cultural difference - I like visiting US clothing stores as my trouser size is below the median by some margin. Over here, some stores do not stock waist sizes over 36"...

[docsimple]

i have changed all kinds of suspension stuff and still have a wobble that presents betweeen 100-105. Slow decel continues the wobble, rapid sorts it out. TBH i was surprised at how much less fun this is at >ton. I love the accel and the spirited turning, but just dont see this as a long distance, high speed bike.
 
My next trick will be to raise the forks 3-5 mm and see what that does.
 
**obviously the cows are mad because they are stuck in England where all the skinny people won't eat them.

[thruster8999]

i have changed all kinds of suspension stuff and still have a wobble that presents betweeen 100-105. Slow decel continues the wobble, rapid sorts it out. TBH i was surprised at how much less fun this is at >ton. I love the accel and the spirited turning, but just dont see this as a long distance, high speed bike. 
My next trick will be to raise the forks 3-5 mm and see what that does.
 
**obviously the cows are mad because they are stuck in England where all the skinny people won't eat them.

 
 
Keep in the throttle and the wobble will go away and before you know it your front wheel will be off the ground. Lol.
I had attached a camera to the front fork to show the wobble and what I found was the front end was getting light when the wobble started to happen. I do think you are on the right path by dropping the fork alittle which should put more weight on the front.
 

[wessie]

What are the cows mad about?

being eaten

[bruceintucson]

i have changed all kinds of suspension stuff and still have a wobble that presents betweeen 100-105. Slow decel continues the wobble, rapid sorts it out. TBH i was surprised at how much less fun this is at >ton. I love the accel and the spirited turning, but just dont see this as a long distance, high speed bike. 
My next trick will be to raise the forks 3-5 mm and see what that does.
 
**obviously the cows are mad because they are stuck in England where all the skinny people won't eat them.

As to front end "wobble" many reasons/possibilities have been discussed. The rear shock spring is too soft & the compression damping is too aggressive, compressing the rear end too much when it hits a bump & sending the shock from the bump back into the chassis. Plus, it seems that a lot of FJ riders do not add spring preload for their weight or added weight, making a front end with not enough weight on it even lighter. There is a history of steering head bearings being improperly adjusted from the factory (generally way too tight). If the front end can't correct + or- a few degrees while running down the road-this is normal and necessary- again it will send the weave into the chassis. Again, while aggressive compression damping in the front forks is great for a smooth racetrack it's not contusive for street riding.If you weight 200+ lbs. and don't add rear preload (or ideally get your rear shock replaced/rebuilt) you're going to have handling issues that appear to be coming from the front end. A 5mm raising of the forks with a stock rear shock is a [em]minimum[/em] to put more necessary weight on the front end. Start at 5mm, then raise 2mm more at a time; you'll know when it's right. 10mm is still safe, especially without making the necessary corrections/replacement to the rear shock.Also at high speed, lean forward & get your body low, elbows in & keep a very light grip on the handlebars.   

[carey]

You've been given a lot of good advice about suspension set up. That would be the first ting I try, but I once had a bike with decel wobble. I finally traced the cause to a faulty tire. A new front tire and the wobble disappeared.

[docsimple]

i dont have stock forks or shock, I probably need a pro tuning of my suspension. I will say the wobble is way worse when loaded down with luggage.

[xlxr]

If you take an average weight rider (160 to 180 lbs) on stock springs and adjust front and rear spring preload to 1/4 to 1/3 total travel, then move the forks up or down in the triple clamps to whatever range is specified in the manual, you will have the range of chassis pitch Yamaha wants us to assume is the safe range of chassis pitch. A good guess for a starting point to set chassis pitch with the fork height is half way in between the high and low limits. Too far one way or another can cause instability problems under different riding conditions.
 
Once the bike starts moving, additional forces start to take effect. Too much compression damping in the forks can keep the forks too high (too much rear chassis pitch), too much rebound damping in the forks can keep the forks too low (too little forward chassis pitch. In the shock, too much compression damping can prevent the shock from compressing, causing chassis pitch too far forward. Too much rebound damping can hold the shock too low in the travel and cause to much rear chassis pitch.
 
Forward chassis pitch tends to make the bike less stable, turn in faster, with less force on the bars needed to initiate counter steering. If you are in a corner, with stable speed and stable turning radius, too much forward chassis pitch will cause the bike to tend to turn in, forcing you to make multiple steering inputs to the handle bars to turn the bike toward the outside of the corner.
 
Too much rear chassis pitch is opposite, bike tends to turn to the outside of the curve, forcing you to make multiple corrections toward the inside of the circle.
 
Once you get preload/rider sag set correctly, damping correct, then set fork height in the triple clamps so chassis pitch causes the bike will hold a line in the average corner at the average speeds you averagely ride at.
 
Ever do a wheelie? Torque of the rear wheel twistes the whole chassis up, extending the forks and eventually lifting the front wheel off the road. Same thing happens at speed, the faster you go, the more the rear wheel torque raises the front end. The less weight on the front wheel, the more likely it will wobble.
 
In addition, with a rider sitting straight up, his upper body acts like a wall, catching a lot of air and twisting the chassis and lifting the front wheel up. I remember stories when the first fully cowled sport bikes came out, guys would crouch behind the windshield up to 150 mph, then suddenly sit up and get blown off the back of the bike.
 
Once you get rider sag, damping, chassis pitch correct, then you can start high speed testing. The faster you go, the more effect little things can cause problems. Rear bags can act like sails, minor defects in tires, loose steering or wheel bearings, one guy reported stock hand guards can cause wobble at triple digit speeds. All you can do is check everything until you find what is causing the wobble.
 
To the guy who mentioned wobble on de-acceleration. My guess is your chassis pitch is too far forward under braking, maybe spring is too weak, too little slow speed compression damping, forks too high in the triple clamps.  Increase spring preload, increase compression damping, lower forks in triple clamps.
 
There is a vendor offering longer chain with longer adjusters, which may be a good idea if you like triple digit speeds.

[betoney]

XLXR and Bruce, Thanks for the comprehensive posts. Good info!
I have my new shock installed and am waiting for Matt to get my forks built, once I am fully "upgraded" then I can focus on getting both ends set up for sag and ride height.
Ya know, for stock components, I really don't find the shock and forks to be "that bad" for everyday riding or commuting. Obviously you start to find limitations when you get more aggressive and proper springs for your weight are a must, but overall I am impressed with the "as-delivered" feel over every other bike I have owned.