I now have a spinner knob installed. I went to the New Freedom, Pennsylvania store of the Tractor Supply Company chain. I had never been in a TSC outlet before. I picked up two: one a Good Vibrations Easy Rider in red, and the other a Countryline Speeco in black. I bought the both of them because I could not decide at the store which one I preferred, and because their prices were modest. After examining the two of them outside the packaging, I decided to install the Speeco.
The Easy Rider is held by a single cap screw. A metal band wraps around the bottom of the steering wheel, and the cap screw holds the metal band in place. Two molded plastic spacers of different sizes are provided for use with steering wheels of various thicknesses. The Ventrac steering wheel called for the thinner of the two spacers.
The Speeco has a top plastic piece, to which the knob is attached, and a bottom plastic piece. Viewed sideways, when installed, the bottom piece looks like a C rotated 90° counterclockwise. The lower portion of the top piece looks like a C rotated 90° clockwise. The two abut, gripping the steering wheel, which lies in the circular void between the two pieces. Two cap screws hold the two pieces together. A strip of rubber is supplied for use on thin steering wheels. It was not necessary to install the strip on the Ventrac steering wheel.
A total of four cap screws are supplied: two each of two different lengths. The thickness of the steering wheel determines which screws one uses. I used the longer ones.
The surface area of contact between the gripping portions of the Speeco and the steering wheel is substantially larger than the surface area of contact between the metal band of the Easy Rider and the steering wheel. Also, the fact that the Speeco uses two cap screws to hold the Spinner Knob assembly to the steering wheel suggested to me that the force of adhesion would be more evenly spread out, and that the Speeco would be more reliable and durable.
The Speeco Knob, when mounted, is centered between the inner and outer walls of the steering wheel. The Easy Rider can be installed so that the Spinner Knob is either slightly toward the inside or slightly toward the outside.
I'll keep the Easy Rider as a spare just in case the Speeco fails. That said, if the Speeco lasts a long time but eventually fails, I intend to get a Speeco replacement.
After installing the Speeco, I went out to take the 4500Y for a spin (pun intended). What a simple thing, but what an improvement. It is so much easier to steer with the spinner knob installed! I wish to express my thanks to a forum member for urging me to get one.
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As I mentioned above, this was the first time that I had ever been in a TSC outlet. Lots of stuff there.
John