Weight Distribution, Road Crown and Handling

Even if you pack unevenly, you naturally end up with an even weight distribution while riding any two-wheeled motorcycle because you subconsciously center the wheels under the vehicle. That's just not so with a sidecar rig. My sidecar is pretty much like any other in that it has a third wheel and the tub (the third seat) rides above (or is fastened to) the frame that bridges the third wheel and the motorcycle. And in my case, all of that 350 pounds of weight plus passenger and anything else that I can stuff in the chair is bolted on the right side of the bike. The uneven weight distribution plays with your handling.

You compensate for your unequal weight distribution with sidecar alignment. The three elements that you are (or should be) in control of are toe in, lean out and vertical straightness of the sidecar wheel. In most cases, the one element that you don't have any control of is sidecar wheel lead. A good sidecar design should have the chair's wheel positioned somewhat in front of the rear wheel of the motorcycle. How much lead is determined by the design of the sidecar and the motorcycle itself.

Toe in refers to the direction of the sidecar wheel relative to an imaginary line that you draw through both motorcycle wheels. All sidecars should have some toe in and mine is set to 3/4 inch. Without toe in, the sidecar is always trying to pull away from the motorcycle, aggravating your already out of balance situation.

Lean out refers to the amount that your motorcycle is leaning away from the sidecar. A motorcycle with no lean out will always pull towards the sidecar. This is partly because you have all of that weight to the sidecar side of the rig and partly because the road that you are riding on has a crown on it and you can't automatically adjust for that crown like you would on a two wheeled motorcycle. Setting up lean out is kind of like putting the motorcycle in a perpetual left hand turn (on R/H mounted chairs) which compensates for the two forces that are trying to pull you off the road.

Vertical straightness of your sidecar wheel just makes sure that your sidecar wheel wears down the center.

A properly aligned sidecar should track down a typical crowned road with just light pressure on the handlebars to keep it straight but you will never be able to go any distance down the road with your hands off the handlebars. Notice that I said "typical"? All road crowns and all riding conditions are different. For example, a four lane road with a center median passes through my town which means that the left lane is sloped off to the left. My sidecar is set up for the average road crown in my area but when I ride in the left lane of the highway, my rig pulls to the left. It's unavoidable unless you own a rig that can be adjusted "on the fly".

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