MT09 (FJ) Tracer Steering Wobbling

[Guest dmizer]

Hi everyone! This wobbelingwobbling isn't fun at all...
Actually I been thinking of selling but I try a steering damper first.
Gpr, ohlins, Toby.
I know nothing about steering dampers.
 
Which brand is the best?

As has been mentioned to many others with the same problem:
 
Start by making sure your suspension is set stiff enough, particularly the rear suspension. Increase the preload and try riding it again.

[milton]

Hi everyone! This wobbelingwobbling isn't fun at all...
Actually I been thinking of selling but I try a steering damper first.
Gpr, ohlins, Toby.
I know nothing about steering dampers.
 
Which brand is the best?

Hello 
I have a GPR , i think it's the only one that fits our bike.
 
No more Woobling , new bike
 

[pattonme]

The problem here is that there are multiple seemingly contradictory factors.
 
hard bag are not aerodynamically stable at elevated speeds. I doubt they are rated for anything over 70mph. (I crashed at 128mph with 45L GIVIs on my triumph a few years back. *wicked* tank slapper)
 
Too little rear preload means the weight bias is too far back and while the "raked out" forks would otherwise be more stable because of increased trail, the relative lack of weight on the wheel encourages it to get flighty. Especially since there are plenty of things mounted to the yoke that will catch wind including the operator's hands.
 
Too little fork preload means the bike is oriented nose heavy with decreased trail.
 
Some tires, once worn can have subtle cupping which results in oscillation. I had a front Avon that would shake pretty damn hard but it was small oscillations and never escalated further. Was still a bit unnerving but putting hands back on the bars was enough to stop it.
 
 
If rider sag is set right at both ends the bike should be stable. Steering dampers only hide/mask the symptoms, they do not solve the underlying problem! Yes there have been bikes (eg. ZX10) that were unstable as hell and would tank-slap by virtue of design choices/errors. But the FZ/FJ isn't one of them.
 

[milton]

Steering dampers only hide/mask the symptoms, they do not solve the underlying problem! Yes there have been bikes (eg. ZX10) that were unstable as hell and would tank-slap by virtue of design choices/errors. But the FZ/FJ isn't one of them.

Yes, i agree with you but between hiding the symptoms and being able do drive my bike safely and enjoy it  8-) , and riding always scared  , i prefer using the steering damper   . 
Before i had the steering damper, i've tried several suspension adjusting settings without the expected results. I read several complaints of users in my country and abroad, and the problem subsisted.
 
I never used hard bags and always had this problem.
 

[Guest dmizer]

Yes, i agree with you but between hiding the symptoms and being able do drive my bike safely and enjoy it  8-) , and riding always scared  > , i prefer using the steering damper   . 
Before i had the steering damper, i've tried several suspension adjusting settings without the expected results. I read several complaints of users in my country and abroad, and the problem subsisted.
 
I never used hard bags and always had this problem.

Perhaps you could try riding with the TCS off? I get wobble now only when I hit the throttle hard enough to cause the TCS to fight to keep the front wheel on the ground. You might also try removing your hand guards and adding weight to the end of your bars.
 
It could also be that your bike has a problem, so you might consider telling your dealer about the wobble and everything you've done to try to solve it.
 
As pattonme said, this is a very solid bike once you have it set up correctly. So needing a steering damper is only covering the real problem.

[pattonme]

I forgot the 4th and 5th factors: the uneven suspension damping between left and right fork legs and aerodynamic lift.
 
I finally watched the video of that front-wheel where it starts to shake at the 30 second mark. You can clearly see the fork extending longer and longer the faster he goes. This is aero-lift (and short wheelbase) at work. The 115mph top speed limit isn't such a silly idea now, is it...
 
This bike has a big 'pocket' for air pressure to build up at speed (80mph+) and Yamaha has blocked off spillover on the sides and upward flow. If you look at the Z1000 tourer, the old FZ1 and a bunch of others that can (and are) ridden pretty fast, they don't have the shrouds and they have noses that are canted downward. The FJ has it's 'mouth' open wide and angled upward to catch as much wind as possible. What you need at speed is downforce and the Yamaha is designed for lift; never a good idea.
 
If you're going to ride at 90mph+ you MUST ride 'clean', no top box and no side bags. Also I would remove or cut away as much of the plastic in the cockpit area that prevents air from escaping upward.
 
As to the forks, this is what contributed mightily to my Triumph's stability issues. I had 10mm more preload in one leg than I had in the other. At 80mph even with 50lbs of luggage on the back it was no problem. Just steered a little odd - left was easier to initiate over right. With the shock not sufficiently preloaded for the bag contents I was running nose-light which set up and then quickly escalated the head shake once aerodynamic forces had built up enough.
 
But back to the FJ, when you put the damping all in one leg, the other one is able to move faster. It is the front axle alone that tries to keep things in sync. But front axles flex, there is bearing slop, and minute torque moments introduced every time the suspension moves.
 
A steering damper is still a bad idea - you're taking away the bike's ability to warn you that you're approaching dangerous conditions. The FZ09 was designed for hooning and 'moderate' speeds. It's probably perfectly stable at 120mph (despite it's crap suspension) since aero lift is modest. You can't slap on a big-ass, cupped fairing on a short wheelbase bike with front-wheel lofting tendencies and magically say it'll handle the same way at elevated speeds.
 

[thruster8999]

The video you talked about was mine. I too tried different settings with no luck. The GPR was the ticket for me. I have had the bike with a full load and no wobble. No load no wobble. I do believe that its more of the areo dynamics of the bike to cause the front end to get light and cause this. I would of done the suspenion if someone could assure my that the wobble would be gone but at that time it was not the case. Is the steering dampner masking it? Maybe so but it just makes it more joyable to ride and a piece of mine. Heres a thought. Why do almost all racers (motogp, NW200, and the TT) have steering dampners?

[pattonme]

race bikes are set up for the aggressive end of stability for 'flickability'. And since they get HARD on the power, the front-end gets light even at moderate speeds. They have dampers because the racing organization requires it, because back in the day 70-80's bikes would get out of control since chassis stability wasn't maintained and suspension 'sucked'. And like I mentioned, some bikes (05-06 ZX10 I believe) are like the F-111 figher, unstable at any speed. I expect you could take the dampers off any Ducati in WSB and it would make no difference. Probably the Hondas too. Dampers do serve a useful purpose when landing the power-wheelie crossed up which happens to even Stoner and Rossi. And the guys who do street racing, they've got the bike jumping off berms, hitting man hole covers at 180mph and all kinds of silly.
 
If you're going to do the 'ton' or delve into speeds that the FJ is not designed to handle, then sure, put a damper on there. Suspension balance won't help here where aero has taken over. Just don't mistake the lack of shaking as "alles gut' and keep pushing the envelope.
 
My SV bike would head shake coming out of VIR T10 and down the straight. Shortened the rear shock by 2mm and it has never done it since.

[ULEWZ]

For me, the wobble was only induced with a crosswind while going fast. I always thought that maybe the hand guards were inducing some disproportionate lift, so I removed them. Not sure if it was the new suspension, removing the hand guards, or the GPR, but the wobble is gone. I will know more when I get my ECU flashed and I venture into full ludicrous speeds.
I have heard for years that a steering damper just masks the problem, but riders continue to buy them with absolute great results, so please, if you want one, buy one, and be happy. If it works for you, no one is going to convince you otherwise, because you have first hand knowledge of the characteristics.

[air]

 

I forgot the 4th and 5th factors: the uneven suspension damping between left and right fork legs and aerodynamic lift. 
As to the forks, this is what contributed mightily to my Triumph's stability issues. I had 10mm more preload in one leg than I had in the other. At 80mph even with 50lbs of luggage on the back it was no problem. Just steered a little odd - left was easier to initiate over right. With the shock not sufficiently preloaded for the bag contents I was running nose-light which set up and then quickly escalated the head shake once aerodynamic forces had built up enough.
 
But back to the FJ, when you put the damping all in one leg, the other one is able to move faster. It is the front axle alone that tries to keep things in sync. But front axles flex, there is bearing slop, and minute torque moments introduced every time the suspension moves.

 
So, a pair of new forks...!?
Is that the solution?
 

[pattonme]

No, the solution is to keep your speed within the design criteria, assuming your suspension is balanced fore/aft. Don't run known aerodynamically unstable objects (top box and side case) at high speed. Look on the lid, it should say not rated above 50mph or something like that. Yes, 50. My givi's had those markings or it was on the website.
 
But even 'clean' I fully expect it's the front fairing causing way too much lift. Take out all the body panels near the forks and gauge cluster so the air doesn't get trapped above the radiator and can flow upward past the headstock. It'll probably buffet you but at least you'll keep the weight on the front tire.
 
If you like 100+mph and do so regularly, buy a different bike.
 

[ULEWZ]

If you like 100+mph and do so regularly, buy a different bike.

Got anything positive to say about this bike? We all love our bike. Do you own one yet? You should get one?
 

[pattonme]

I am thinking about it but I have to do something about the stable I have now (6 bikes). I have a GPR on my KTM motard because at 90mph and going over the hump on Summit/Shanandoah front straight the front gets really light and waggles. I tried a couple sessions with the GPR set to minumum and the bike stabilized itself quickly. A dynamically stable bike will come back to stable on it's own.

[wessie]

@pattonme I have ridden quite a few miles on a UK spec. MT09 Tracer (no speed limiter) at speeds well over 90mph with a topbox or side cases (never both) fitted. I have not died so your "MUST ride clean" quote above is just plain scaremongering in my view.
 
Riding any bike on a public road at 90mph is risky and illegal in all but a few places in Europe.
 
We are adults here and make our own choices based on our own ability, experience and perception of risk.

[pattonme]

Ok, so I called Givi and no, there isn't an official speed limit on the cases but he did say that yes, they used to mold a "don't exceed speed" into the lid and that if they don't anymore, 75mph should be considered that advisory limit. "I personally ride faster than that and haven't had a problem".
 
So, to your point @wessie, I wasn't saying "YOU'RE GONNA DIE" but that you should think good and hard because you're opening yourself up to the aerodynamics making everything go pear-shaped in a real hurry.