MT09 (FJ) Tracer Steering Wobbling

[pattonme]

those are max pressures. Now if you're putting 500lbs on the bike (rider, passenger, luggage or some combo) then yes running max might be advised. If the bike was 600lbs or 800lbs instead of 450, I would run higher than 33/33 as well.
 
Owner's manuals have as much mis-information as they have accurate and useful information. Recommended tire inflation is one of those perennially wrong entries.
 
but feel free to experiment.

[buz11]

pattonme, thanks I'll be on the lookout for middle tire wear. At 34 psi my back tire was definitely getting rounded wear during break-in, much more than my front tire at 33 psi. My commute is mostly straight bumpy roads, but the stiffer shocks also help reduce bounce in the curves I find on weekends. I may try another click stiffer on the rear like gkdozer but found that a softer front didn't help my wobble and felt a bit mushier in turns.

[jimf]

your tires are overinflated @buz11. 33 front/rear modulo load is plenty. Also, it helps if you're talking clicks/turns of settings that you indicate from fully in (aka hard). It's not clear if that's what you meant.

my UK version of the manual says tyre pressures are 36 front, 42 rear, in pounds per square inch 
this seems to be universal on sports or sports touring bikes whether of Japanese or European manufacture and is the pressure my local dealer set the tyres too, as did the independent tyre fitter I used recently

Those are the same recommended pressures as in the US.  The FJ is the first bike I've ever owned with recommended pressures anywhere near that high.  Everything else -- mostly Japanese, but with a Triumph Daytona 675 thrown in -- was more like 32-34 front and 34-36 rear.  But my understanding is that the FJ's pressures are not unusual for touring bikes, especially loaded; this is the first bike I've owned that wasn't either a "lightweight" cruiser or a sportbike. 
I haven't felt the need to deviate from the factory recommendations because the handling is fine with me (205lbs) and partially loaded luggage (probably 30-35lbs) on the bike, but I could see how it could be too high if you're a featherweight and running the bike naked.  I've let pressure bleed down through laziness and not had the handling significantly change as low as 33 and 38, or at least not enough for me to notice on my commute.  If I were running twisties regularly I bet I'd be more sensitive.
 
Fully loaded for touring?  The stock pressures were fine as far as I was concerned.  Handling good enough to scrape hard parts, to snap through technical turns with alacrity, and no trouble with traction wet or dry.  As a result, it's hard for me to believe that the Yamaha recommendations are terrible in this case (unlike, say, their chain slack measurement).
 
YMMV, especially if you're not running the stock Dunlops, or you're lighter than I am, or you don't use luggage, or you're running with a pillion, or the moon is waning....

[toast]

I have experienced the steering wobble you guys are talking about but only with FJR bags on. I had the bike around an indicated 105mph on *ahem* the track... and did notice the bars start to rythmically wobble back and forth, the bike felt steady but the front end was definitely light. It is more likely to shake it's head when changing lanes over big grooves parallel to the bike as well. Nothing scary though, just stay light on the bars and it corrects itself.
 
Without the luggage I haven't noticed anything even up to the speed limiter while accelerating hard.

[wessie]

I have experienced the steering wobble you guys are talking about but only with FJR bags on. I had the bike around an indicated 105mph on *ahem* the track... and did notice the bars start to rythmically wobble back and forth, the bike felt steady but the front end was definitely light. It is more likely to shake it's head when changing lanes over big grooves parallel to the bike as well. Nothing scary though, just stay light on the bars and it corrects itself.  
Without the luggage I haven't noticed anything even up to the speed limiter while accelerating hard.

I think your comment about being light on the bars is correct, as well as my advice of leaning forward during hard acceleration.
 
A mate pulled out of a ride today and my 80 mile loop in the Cotswolds was rather more spirited than usual. If your arms are too rigid then it is easy to get an inadvertent throttle opening, especially in A mode. Today, I kept it in std but had the revs very high, seeing some outrageously naughty speeds but kept away from the rev limiter and all was well. On fast bumpy sweepers you do need to be pretty firm with counter steering but this is no different to most Adv bikes with softish suspension that want to pitch and wallow in bumpy corners. 
 
I'm not sure what I have to do to get the last cm of chicken strip to disappear on this Roadsmart 2 - I thought I was going to scrape my elbow on one roundabout in a Super Slick roundabout manoeuvre at one point. Still a cm left...

[pattonme]

I think I've found the culprit for the 'not stable' at speed. If the 'Internet' is right, it's the ridiculous rake and trail numbers. 100mm@24deg. The FZ09 has sane values of 103@25. Now admittedly swingarm pivot and other factors come into play but 102@24 was the reason why the '04 ZX10 required a steering damper installed from the factory.
 
The FZ1 runs 109@25 as do a slew of others in the low hundreds and 25deg. The most recent R1 (not the new one) runs 102@24. So Yamaha gave a mid-weight budget tourer more aggressive steering than an R1?!?!
 

[jbossm7]

That is what a "motorcycle" guy at work told me. I am willing to bet to you have indeed uncovered the truth. So what do we do now? Stay under 100 mph?

[rocky5000100]

My 2005 R6 had a Rake and trail of 24°, 86 mm. The R6 is well known for it's good turn-in, and it always felt stable at speed to me, and I've had it on the track. The newer R6 has 24°, 97 mm.
 
I don't know enough about rake and trail to comment further haha.
 
Edit: Just read this article, which summarizes things well.
http://www.ridermagazine.com/motorcycle-features/understanding-motorcycle-rake-and-trail.htm/
 
 

[nihilist]

I tested this and found the wobble started at about 170km/h (I have side and top cases and a puig touring screen, for reference). It's definitely disconcerting, but I'd have bigger problems if I chose to spend any time at that kind of speed - namely, losing my license because that will get you a "stunt driving" ticket. That involves extremely stiff penalties like losing your license for 2 years (both motorcycle AND car), and a minimum of doubling insurance rates. A second conviction can result in jail time and a 10 year license suspension. All this just from being clocked at over 50km/h over the posted speed limit.
 
Needless to say, I have no interest in making a habit of exceeding 150km/h at any point.

[pattonme]

@rocky5000100 those were measurements you had done? The stats I'm seeing says 96@25d for the 05R6 which is perfectly in line with pretty much every sport bike of the last 15 years across all brands. The '05 GSXR750 had 23.8deg rake with short trail and Traxxion makes extended length fork caps for that series to get the Rake back under control (somewhere around 24.5).
 
I'm not saying 100@24 is guaranteed under any and all designs to be a problem, there's more to it than that. But it's a very questionable design choice for anything that isn't a full-tilt sportbike.
 
So if your bike is properly balanced, and you like going really fast and especially with luggage, and you want to push past the weave/wobbles, you probably want a damper. Just don't expect it to save you once you go over the inflection point.

[rocky5000100]

@rocky5000100 those were measurements you had done? The stats I'm seeing says 96@25d for the 05R6 which is perfectly in line with pretty much every sport bike of the last 15 years across all brands. The '05 GSXR750 had 23.8deg rake with short trail and Traxxion makes extended length fork caps for that series to get the Rake back under control (somewhere around 24.5). 
I'm not saying 100@24 is guaranteed under any and all designs to be a problem, there's more to it than that. But it's a very questionable design choice for anything that isn't a full-tilt sportbike.
 
So if your bike is properly balanced, and you like going really fast and especially with luggage, and you want to push past the weave/wobbles, you probably want a damper. Just don't expect it to save you once you go over the inflection point.

Those were from Wikipedia, but must be wrong because other sites I'm seeing now say what you're saying.  Whoops! I definitely see a damper, and other suspension upgrades in my future.
 

[wessie]

So what do we do now? Stay under 100 mph?

No fun in that!
 
I'd rather die when on the gas than being T boned by some myopic old gimmer who should have sold the Honda Civic and retired his licence a decade ago.

[Guest dmizer]

I think I've found the culprit for the 'not stable' at speed. If the 'Internet' is right, it's the ridiculous rake and trail numbers. 100mm@24deg. The FZ09 has sane values of 103@25. Now admittedly swingarm pivot and other factors come into play but 102@24 was the reason why the '04 ZX10 required a steering damper installed from the factory.

These are the numbers listed on the official Japanese Yamaha website spec sheet here: http://www.yamaha-motor.co.jp/mc/sportsbike/mt-09-tracer/spec.html ... look for: 24°00′／100mm

[Guest highplainsrider]

I think there needs to be another variable to induce the wobbling. My bike is completely stock and I don't have the wobbling issue even up to 115. If geometry was the cause, how do you explain people who don't have high speed wobbling? 
 
I'm thinking that tires may play a bigger roll. Bad batch of dunlops maybe or certain wear patterns?

[pattonme]

suspension damping frequency and loading bias is more likely to be a contributing factor than tires. Not to say that cupping doesn't also contribute to the front's wandering. I've had some BT and Avons do some very odd things...
 
Any proper tourer has by definition a relaxed rake and longish trail. Yamaha is WAY off the reservation with the FJ09. I don't know why they thought it was a good idea.