Front end wobble at highway speeds near large vehicles

[fj09viking]

Maybe this is why mine is so stable!😉

 

 

Edited September 16, 2020 by fj09viking

[thewrenchbender]

Got the FJ GPR stabilizer fitted about a week ago. 

Took quite a bit of filing on the LH portion of the “bridge” fitting that straddles the frame neck.

Initially, the bridge fitting was twisted to the left so much that it didn’t clear the top fork clamp when cranked to the right/alignment from the actual stabilizer to its plate was not even close.

Relieving the left side allowed it to rotate around the air box mounting bolt to properly line everything up.

Have had three straight days of some fairly high cross-winds on the highway commute, and currently set on “9” is solid as a rock.

Still get pushed around by the wind, but don’t get the “weave”...and is eliminated at a ton-up also.

Did have to remove the motopump risers due to the stab bracket lifting the risers 8mm up off the top clamp. Woulda had to do some serious cable/harness tweaks to get enough slack, was borderline tight with the risers. Hoping my shoulder/neck can deal with the “change”.

[Ride365]

After a brisk freeway blast today at 65 mph to 75 mph, I am a bit irritated as mine is having this phenomena. If I am pretty much away from any traffic in front of me the front end is stable, but add some cars/trucks and in particular some big rigs.....and I feel quite the instability and hunting of the front suspension due to turbulent air. It's honestly enough to concern me, in particular if the roads were wet and in the rain. Set my suspension setting per Dave Moss "he and I are about the same size", so it looks like I have perhaps some more adjustments to make or try another windscreen. So weird.....I have NEVER had a bike do this, and I have owned more than a few.

Edited October 11, 2020 by Ride365

[PhotoAl]

Not saying your doesn't do it but we both have 2020s and mine has never given any hint of instability.  It's about the same as my BMW F800GT was as well as my CBR600RR and ZX6R 636.  Did notice with stock screen that I would get alternating left right blasts to my shoulders from wind.  The MRA windscreen eliminated that but bike never wandered or anything - it was moved around by the wind a bit but seemed like the tire contact patches were going in a very straight line and the bike was moving sided to side a little moved by wind blasts.  Have seen this passing trucks that were going well over 70.  Makes me wonder if there is something in the bike setup or adjustment that contributes or causes what you are seeing/feeling.  

I might suggest loosening the triple clamps and bouncing the from a few times to make sure they are square as well and loosening the pinch bolt on the front axel and bouncing the front to make sure it is in the right place - Dave Moss has a video on this.  Gave my Dunlaps 222s away after 2,400 miles and running Michelin Power 5 front and road 5 rear but no difference in stability on the interstate.  

EDIT:  Like the writeup on the steering damper, put an Ohlins on my ZX6R 636 which didn't come with one.  Cured a bit of head shake I was getting but also smoothed out little twitches in cornering - bike felt smoother overall and at a low setting - 3 out of 12 or 14 if I remember correctly.

Edited October 11, 2020 by PhotoAl

[Ride365]

Mine is doing it for sure, I'll get it figured out one way or another. Zero issues riding any where else at any speed, but something going on when dirty turbulent air is in front of me on the slab in traffic.

[Bill H]

On 9/8/2020 at 8:31 AM, Gamarth said:

Morning all!

I bought a 2019 Tracer GT back in May of last year and due to some life complications, didn't get to ride it all that much. For the first time yesterday I did my first trip that wasn't just commuting and did about ~250 miles. I've noticed that when i'm at highway speeds, if i'm near a large truck/SUV or an 18 wheeler, that the front end wobbles a decent bit. Not enough to be a tank slapper, but it does make me a decent bit nervous. I understand that the bike is being battered by wind during situations like this, but I don't recall having this issue on my previous bike (07' Suzuki Bandit 1250)

Has anybody else experienced this? Any advice would be greatly appreciated. 

hahah after reading some of these comments good luck ,,wow,,so that was one of the first things i noticed on my 2020,,mine does it do

normal freeway speeds you  dont have to be behind a truck ,,all it takes is some side or head winds for me,when the leaves on the trees arent moving around the bike is fine ,{i use them as a gauge}  just for the hell of it i purposely got in the draft of an 18 wheeler and  it was really bad ,,i mean ya thats to be expected right but  this was a little nerve racking  ,,,,I wanted out so i downshifted to 4th and blew by him only to come flying up alongside a sneaker cop in a  black  unmarked ford,, those guys are hard to spot,,anyway i backed off at 85 mph ,,he tailed me for a bit and that was that ,,i got lucky that day. i had open road ahead and was gonna ride it out for a bit . so  i took off the gaurds cause i dont like the looks of them and they dont seem to serve much purpose ,,but that didnt make a diff,,i cut about 5 inches off screen cause it sucks,,that didnt make a diff and i lowered forks 4mm and that didnt make a difference ,,i think its like someone else said shitty aerodynamics

[Ride365]

Well I have to figure this out one way or another, as this is gonna be my long distance touring machine. 

[PhotoAl]

My 2020 is stable, rode it today and was behind a big tall van, getting pretty good turbulent gusts but the bike was stable.  I did not have the side cases on but that has not made  a difference before.  I'm down 7mm in the forks but didn't have any issues when I rode it home from South Dakota which was 1,400 miles of 2 lane to 4 lane to interstate and some quick riding.

This is a quite perplexing issue and have a hard time believing it is just aerodynamics.  The fact that it affects some bikes and not others makes me wonder if something is a bit loose.  

I ride with my elbows bent and try and have a relaxed grip but sometimes just get a bit of a tight grip.  Ive never owned a "big, heavy, stable" bike.  First was a Ninja 250 and it was buffeted by winds from trucks but it would cruse all day at 80MPH with no issues.  Bikes I've had since then have all been between 425 and 470 pounds and they would get buffeted but always tracked straight and true.  The Tracer GT is very light on its feet and I love the way it moves but mine does not weave at all.

EDIT:  Want to be clear I'm not saying you folks with the weave are crazy or bad riders, it is perplexing there seems to be significant differences in some bikes.

Edited November 5, 2020 by PhotoAl

[Dodgy Knees]

When passing big trucks i get buffeted in my car.  Keep clear of truck as much as possible.  Trucks make turbulence.  🤔

[Ride365]

I recently dialed down both the front and rear pre-load from the previous recommendation of Dave Moss that I had been riding with, that has really helped with the instability I was having. I do agree there is perhaps something up with the OEM tires that induces a wobble, hope to wear them out quickly and get upgraded. I don't notice any bad buffeting from the screen, but agree it could be a helluva lot better and more aerodynamic........loving this bike by the way.

[Ride365]

Any opinions/experiences on whether I should raise my fork tubes 5mm or not, and if so wouldn't that potentially make the front end even more skittish? 

[peteinpa]

Raise it to 5mm, try it, take it to 10mm. Mine is at 10mm, remember my wheelbase/swingarm is shorter than yours.

[betoney]

18 minutes ago, Ride365 said:

Any opinions/experiences on whether I should raise my fork tubes 5mm or not, and if so wouldn't that potentially make the front end even more skittish? 

As @peteinpa mentioned, try it a few millimeters at a time and see how it feels, - trial and error.  It only takes a few minutes, just do one side at a time.

[peteinpa]

What tire pressures are you running?

I've got 42 rear and took the front from 36 to 42 and it got much lighter. going to drop it down and try 38. OEM tires.

[Coop]

On 9/8/2020 at 12:18 PM, knyte said:

Pretty sure I read in the manual this is what A mode is for - teleporting past semi trucks

I thought A was to scare the poop out of old men who thought it was in B drive.