wobble of near tank slapping magnitude

wondering if anyone eles has had similar experiences, never have I had this at this magnitude before going darkside

twice now, once passing a chip truck on a long slight downgrade, the other passing a tour bus on a steep upgrade, both were under full throttle acceleration as I went thru the "wake " of the vehicle, I've had little wobbles before, noting that scareed me, this did, both were questionable passes that I committed too

Bike is a 07 Suzuki V-strom 1000, rear tire is a General Altimax Artic 205/50-17 (vs 150/70-17 oem size), front tire is a Metzler Karoo 2 T 110/80-19 (70/30 knobby DualSport in oem size) last winter I ran a studded Karoo T same size

Ive recently lowered my pressure, first, I started at 45, and ran it quite a while at that pressure, it worked great thru the winter, as more agressive riding time arrived, the countersteer effort was annoying, I stasrted playing wiht my pressure, first dropping it to 32 for a few tanks of gas, then down to 25, at 32, countersteer effort was next to nothing like with the normal bike tire then I dropped it to 25, and put 500 or so miles on at that pressure, at that pressure, I could feel the radial rolling under the wheel in corners, i t never quite gets on to the sidewall, but I can feel a "give" sorta, but, the tires are sipped, so their kinda squirmey on some surfaces anyway unlike mosta you cruiser guys n gals, your darkside tires are usually close in size to the stock MC tire specially if you have a 15" rear, gets harder when your rear is a 17", and right now, that 205/50 I have that is intended for a 5½-7½wheel is spooned on to a 4" wheel

I've gone back up to 30, I wonder if the tire rolling under the wheel in quick cornering contributed to the wallowing that started increasing in magnitude to the point I could barely hang on, or was it the knobby front tires

I'll prolly be investing in a fork brace and steering damper but I'm also looking for a practical way to install a wider rear wheel that would still allow me to easily swap to an oem bike tire & wheel, so far, all I've found are expensive wheels machining or swaps that require caliper (mount) modifications, making it impractical to swap back and forth from the darkside

Most of the shaking we get is from worn out shock bushings.

Jerry

jedishon wrote:Most of the shaking we get is from worn out shock bushings.

Jerry

Or the crappy Honda 1300 Steering Stem Bearings.

Running a non run flat on my wing I too get the wallow in the wake. It is always worse when I don't need it to be (committed to a hard pass). This is seriously amplified when I am running lower pressures. The tire wallows enough under this 1000 pound machine at full pressure without my adding to the equation by dropping the pressure. The guys running the run flat tires swear they take all the unfun out of it and give a much firmer ride. I will find out fairly soon.

For now jack the pressure up a few clicks and try that.

See you out there
Smokey

Mine will get the wobble around 80 passing or not if I let the pressure get down to 30 or below.If I run 32 to 36 I am good to 130 at leaste.

+1 on the steering head bearing... That was my first thought as I was reading..
Get some "All Balls" head kit... And slap them puppies in there...

LadyDraco wrote:+1 on the steering head bearing... That was my first thought as I was reading..
Get some "All Balls" head kit... And slap them puppies in there...

I agree too. I have the alls balls bearings and still got the wobble with worn out shock bushings. I'm on my forth set now.

Jerry

smokey2255 wrote:Running a non run flat on my wing I too get the wallow in the wake. It is always worse when I don't need it to be (committed to a hard pass). This is seriously amplified when I am running lower pressures. The tire wallows enough under this 1000 pound machine at full pressure without my adding to the equation by dropping the pressure. The guys running the run flat tires swear they take all the unfun out of it and give a much firmer ride. I will find out fairly soon.

For now jack the pressure up a few clicks and try that.

See you out there
Smokey

interesting information, I plan for my next tire to be a Nokian Hakkapeliitta 5, runflat is an option

jedishon wrote:

LadyDraco wrote:+1 on the steering head bearing... That was my first thought as I was reading..
Get some "All Balls" head kit... And slap them puppies in there...

I agree too. I have the alls balls bearings and still got the wobble with worn out shock bushings. I'm on my forth set now.

Jerry

shoulda mentioned in my first post, all new suspension, shock, rebuilt fork, major service about 2500miles(1 month) ago, steering and suspension are better than new, sprung and valved for my weight, bike is about 500lb wet, I weight 300 with gear, shock is WP Suspension, 4014Spin

first scary experience was with 30% tread, sawblade and scalloping wear on an old Karoo front, second time was with brand new Karoo front

I feel the wallowing is from rear tire sidewall flex, pressure stiffens it up, but also increases steering effort, don't know if the effect is exadurated cause I got the 205 spooned on to a 4" wheel

Try adjusting you windshield or remove the bags on the back if you have any? We have seen this also cause a wobble.


...................bobby

Could also be a broken belt in the tire.
but I would go up in air first. If its a belt it will wobble withal pressure.

Jerry

Hey CWF, I was plating with my air wings on the slab tonight, learned that I could open them and the wobble would noticibly lesson as I was in the tail wind of the big rigs, close them and instant increase in wobble.

We have learned through trail and error around here that the car tire does amplify any other issues a bike may have. Some of these are inherent to the bike but most have been maintenance issues. Some have also been add ons affecting the ride. On my VTX my fairing and bags and trunk all each individually had adverse effects on the ride, learned that upping the air pressure tended to mitigate those issues. Same thing with the wing.

I think that if you were to run up the pressure you will find that in a few hundred miles riding time you dont notice the extra effort it takes to handle the bike.


See you out there
Smokey