"The watts system consists of two horizontal rods of equal length mounted at each side of the chassis or axle. In between these two rods, a short vertical bar (bell crank) is connected. The center of this bell crank – the point which is constrained in a straight line motion - is mounted to the center of the axle or coach framework (inverted). All pivoting points are free to rotate in a vertical plane." -WikiPedia
Watts Linkage?
Think about how much work is involved trying to stay between the lines on the highway. Constantly see-sawing back and forth dealing with wind, road ruts and passing trucks. The design of the Roadmaster RR8 chassis was innovative but had a significant problem. The suspensions trailing arm system and its single Panhard bar allows the H-Frame (axle) to move on its own independent of the coach. This action is sometimes referred to as "Duck Walking".
The addition of the Watts Linkage on the front and rear (if available) stops this. In the above image you can see the center of the axle is held in perfect alignment while the vehicle moves up and down. Holding the axle dead center in the coach stops the wandering. It's an amazing change in driving. No longer are you exhausted after driving just a few hours. Our users report trips from 6, 8 and 10 hours without the fatique.
I've heard of Cross Bars and Rear Watts. Do I need both?
The rear suspension on the RR8 chassis uses trailing arms to position the axle fore and aft under the coach. These trailing arms are made of 2" x 2" tubing and are more than 6' in length. Given the long length, the trailing arms actually deflect when side forces are applied to the coach (such as broadside winds or passing trucks). You can add to this the movement from the 10 rubber bushings used in the arms and panhard bar. This deflection is small but more than enough to make the rear of the coach wander constantly (Duck Walk). Triangulating these trailing arms with Cross Bars (sometimes called Diagonal Track Bars) holds them in perfect alignment while still allowing proper motion of the axle. If you tow a vehicle you should consider the rear watts (if available). Using both the rear watts and cross bars is an unbeatable combination. Please take a look at the following video produced by Harry (IRV2 HappyCars) on his trip to the Quartzsite Monaco Owners Gathering demonstrating the results of his Watts and Cross Bar upgrades.
Watts linkage (also known as "parallel linkage") is a type of mechanical linkage invented by James Watt (19 January 1736 – 25 August 1819) in which the central moving point of the linkage is constrained to travel on an approximation to a straight line. It was described in Watt's patent specification of 1784 for the Watt steam engine. It is also used in automobile suspensions, allowing the axle of a vehicle to travel vertically while preventing sideways motion. -WikiPedia
The Watts Linkage does indeed do more. It reduces body roll (sway) as well. Body roll is defined as the coach tilting left and right during turns. This tilting is centered around the "Roll Center" of the coach as set by the location of the Panhard bar. On a Monaco RR8 chassis this Panhard bar is located high above the axle, near the floor of the coach and near the top of the air bags. Being this high limits the air bags ability to control the roll (sway). Our Watts Linkage mounting is located at the H-Frame level well below the air bags creating a new lower "Roll Center". This makes the air bags much more efficient at limiting body roll.
Think about how much work is involved trying to stay between the lines on the highway. Constantly see-sawing back and forth dealing with wind, road ruts and passing trucks. The design of the Roadmaster RR8 chassis was innovative but had a significant problem. The suspensions trailing arm system and its single Panhard bar allows the H-Frame (axle) to move on its own independent of the coach. This action is sometimes referred to as "Duck Walking".
I've read on the forums that it does more than reduce the wandering?
