We’ve all experienced it: you’re hard on the throttle, the front gets light and the next thing you know the bars are wagging like the tail of a dog that just heard “car ride.” Headshake, tank-slappers, speed wobbles, bar wag, it goes by many names but the toe-curling experience is all the same. In the most basic sense, headshake is the result of the front tire returning from being airborne caulked left or right. The ensuing slap kicks the tire to the opposite side and a violent back and forth motion commences to a strength that could buck you off—it can occur under hard braking as well. The best way to survive a slapper is to just avoid it all together. Scotts Performance has been in the business of stabilizing the shake since sportbikes tightened up into quick-turn machines decades ago. Today a Scotts’ stabilizer offers an almost infinite range of adjustability for track to street to stunt applications absent from OE units, so SSB rode up to where it all started and sat down with the man himself to find out more.
Scotts Performance opened in 1974 in Glendale, California, as a suspension repair shop for local racers. Scott Forward, the owner, always had an affinity for riding and later became an accomplished Baja 1000 racer. Dirtbikes came first but as sportbike rake angles became more aggressive for quick-turn handling, dampers became sought after in the street market. Scotts partnered with Öhlins Racing in 1987 and the rest is history as Scott recapped, “I would say ’87 was when things made a big turn because that’s when we really got hooked up with the stabilizer itself. We were over in Europe for the International Six Days Enduro event and that’s when I met Lennart Sundahl. He was the guy that actually owned the original stabilizer patent, which he was actually designing for the landing gear of military aircraft. That’s when the White Brothers (off-road brand) picked it up in the U.S. through Hi-Point. White Brothers and us were the only ones doing suspension modification here but they found the stabilizer wasn’t their forte so they handed it to us and we took it on. That’s right when I started racing Mexico (Baja 1000) and we started developing and adapting it to our needs.
Spying into the internals...
Spying into the internals better explains what is going on inside one prolific motorcycle invention.
Then Öhlins brought Lennart on board and bought the stabilizer patent rights to help develop GP bikes with a rotary rear shock, with the possibility of this idea becoming included for all production bikes. Suzuki actually built one for their TL1000 but there were some legal issues that came up with the Suzuki design. As we went on through the years and worked with Öhlins we found out that they could not keep up with our progression; they are like dealing with the government, slow and unresponsive to the needs of the end user. Quality control became an issue for their early systems so we started manufacturing parts over here to repair them. It came to the point we were manufacturing enough stuff to create our own dampers while also doing a lot of our own R&D. We ended up cordially going our separate ways and at that point the original patent had expired so we took the stabilizer in our own direction.”
How It Works
Scotts dampers are not the cheapest on the market but with a higher price comes near infinite stabilizer adjustability and install-and-forget durability. Why is adjustability important? A rider going for a top speed record doesn’t need to turn quickly and therefore can utilize stiff damping resistance that makes pushing the bars feel like punching through quicksand but keeps him protected deep into triple digits. A commuter doesn’t want to fight the bars to turn at any speed and that’s when a softer setting is more desired. A Scotts’ unit uses a Base Valve and High-Speed Valve that controls how much oil passes through the circuitry by the opening (soften) or closing (stiffen) of small holes. A fixed-in-place rudder-like component pushes that oil back and forth through the valving as the head unit moves with the bars. Side Sweep Controls then delegate to what degree of bar turn damping resistance can be felt. Getting the right amount of damping resistance is a matter of where you are riding. No matter what bike a Scotts’ stabilizer is attached to the function is the same as the headcheese explained: “It operates under the same principle as your front forks, except the design function is to control unwanted side-to-side energy. Valving inside the unit reacts to the slightest of jolts that are transferred through the forks and triple clamps. Internal circuitry progressively absorbs the energy that you normally would have to stop by holding your bars tighter, energy that would have been received through your bars. The stabilizer reacts instantaneously, absorbing any unwanted movement. Your suspension was designed to handle the vertical movement of your motorcycle. Our stabilizer completes the suspension package by controlling the unwanted horizontal movement.”
Is It Worth It
The front tire can get caddywhompus...
The front tire can get caddywhompus quick when rolling a stoppie so watch out. (Left) When the front goes airborne and doesn’t drop straight prepare for bar wag.
At the end of the day it is about protecting your two-wheeled investment. Stock units do their job just as a stock exhaust does. There is almost always room for improvement when dealing with production parts and for those that want a greater level of performance there is the aftermarket. Some will attest a damper is just an unnecessary crutch but those same people will almost definitely rethink their sentiment when a freeway tank-slapper sends their feet flying and riding line out of whack. Check out SSB’s Scotts Performance video on our YouTube channel for further coverage on this topic. SSB