Weave / Wobble on 2003 ST1300

I have a 2003 ST1300 which has a definite weave problem when cruising around freeway ramps (long sweepers, not cloverleafs) at moderate to slightly higher than moderate speeds. The wobble only hits if I remove my hand from the throttle or from both grips, which I obviously don't do at freeway speeds. This bike just turned over 53K on the odo, has almost new tires and has never been wrecked. I have a nearly new Dunlop Sportmax D220ST Radial on the rear in 170/60 R17. I have an also nearly new Dunlop D220F D220ST in 120/70 ZR18 on the front. Does anyone have any experience with this weave problem? The wobble isn't really a big issue, as I tend to keep both hands on at almost all times. The high-speed weave, however, is very disconcerting. I've been riding for over 40 years and I've been in high speed wobbles, weaves and just about every other situation of this type that I can imagine over the years. I've had every brand of Japanese bike, as well as 3 Harleys and a Triumph. I never experienced anything like this with my other bikes, except once in the 70's on a bike that was notorious for a weak frame. In the 70's I had a Kawasaki 500 2-stroke triple and that thing had the worst wobble you can imagine. If you tried to accelerate in a curve, you'd just about get a tank-slapper every time. At any rate I've been hoping that someone on the forum has had this problem and knows how I might stop, or at least mitigate the high speed weave. BTW, thanks to all for great advice in my previous posts. Also, I'd like to give praise to Seth Laam for a great job on rebuilding the stock seat into something worth riding. I did NOT like the stock seat and Seth did a great job at a very reasonable price. This is my first ST13 and I otherwise love the bike. I sold my last (and I mean LAST) Harley Superglide on a Thursday and by that Sunday I had found this ST, which I promptly took to a dealer and had the (quite pricey) 50K service fully done, since there were no service records provided with the bike.

In my experience the weave has been caused by a large top case or by a rear suspension ride height modification. I don't like dun lops but doubt they would cause this problem.

I get a high speed weve only under the conditions of top case installed and no pillion.
In that instance it is very predictable at 110mph (actual). Otherwise change either of those factors... never an issue.

Other then that, check your pre-load.
Check your tire pressure.
ST's are notoriously undersprung for the average American male.

Thanks. I'll remove my Givi trunk and try again.

The front wheel may have been installed incorrectly after the most recent tire change. Search this site for installation procedure and torque values.

Also consider the rear suspension setting. If too soft the front will lift at speed and hunt. Lastly, a top box at high speed will also act as a sail and lighten the front end at high speeds and allow the front wheel to hunt.

Since you don't like the Dunlops (which were new on the bike when I bought it), what tires would you recommend for this bike? Two bikes ago, I had a Concours 1100 and I changed the Bridgestones over to Avons and I was very happy. On that bike, the tire sizes limit your choices badly.

Yea - the top box removal will prob. fix it. Also, U might have to match up the F & R tires. Good Luck

And it could be the steering stem beariings I would try the other fixes first crank up the pre load and work from there do one fix at a time so you know what if anything fixed it.

Thanks to everyone who have responded to my questions. After some real seat time, the ST13 has really put the fun back into riding for me. After my last bike (An '05 Harley big twin that was already leaking oil at only 4,000 miles), this ST has reminded me why I've been riding for over 40 years. I've had every brand of Jap bike, plus 3 Harleys and a Triumph. Before that '05 Harley was a Concours 1100. That Connie was a bullet, but after an hour on the road, I would have numb hands from the vibration in the grips. This ST has me wanting to ride much more than I ever wanted to cruise on that Harley. I'm disappointed that they quit building the ST, but they're just following the money. The only "cruiser" bikes that I've ever owned were Harleys, and to me they just don't perform well enough. Safe riding to all and thanks again.

I'm off to ride without the top box now. Thanks.

I think the OEM fitment Dunlop 220s for the ST1300 was discontinued some years ago. I'd check the DOT date mfg code on the sidewall. It might not have anything to so with a weave but old tires can't help.

If the rear shock preload gives no resistance when turned clockwise from fully counter clockwise the adjuster needs attention to restore its effectiveness. The wheel turns 18 turns or 36 clicks. A stock ST1300 needs some to "a lot" of preload to firm up the rear shock and help quell the predisposition the ST has to high speed weave. The weave usually doesn't start until 115 mph or more (if it appears at all). This isn't just a feeling from grooved concrete freeways is it?

Crank your preload up a couple of more turns, make sure you have 42lbs air in the tires, A couple lbs more won't hurt. About time for a fork oil change and while you are doing that, drop in some Sonic Springs.

I bought my bike with the Dunlop 220's and they were terrible.Noisy and uneasy feeling.
Everything else I've run has been much better.
I've run Bridgestone BT020F's, Michelin PR2, PR3 (now they have PR4's)
I have a set of Bridgestone T30 GT's to install in a few thousand miles.

I have a 55 Givi one of the largest boxes.

Like others mentioned don't be afraid to crank up the rear preload that does it for me!!!!

Good luck the ST a great bike!!!