The rig: a 94 Kawasaki Voyager XII tugging a Daytona 2+2. I'm considering a car tire on the rear. A 160 80 15 is commonly fitted on the rear by the two wheel darkside Voyager riders. Tire wear is even an normal but the rear tire is "done for" in about 4000 miles or less. The rig tracks true and the electric servo lean out adjustment is extremely effective in offsetting right-pull from additional sidecar loading or when riding on long straight stretch with noticeable camber to the shoulder. I'm wondering will the flat profile of the car tire mitigate or even negate the effectiveness of the adjustable lean out feature.
All experience, opinions, and comments welcome.
A car tire on the rear makes little difference. On the front it is an entirely different story. I will assume you are only asking about the rear. If the diameter is the same you should not need to make any adjustments to the alignment and your electric trim (Or in Champion speak T.I.LT.) However I am sure as you have been looking into this a bit you know that a 15 inch motorcycle rim is larger diameter then an automotive rim by a considerable margin. Lots has been written on this topic as such I will not go into it. If you have not looked into it do a quick search of this and other forums. If not done correctly there can be some real safety concerns.
Jay G
DMC sidecars
866-638-1793
www.dmcsidecars.com
I am in agreement with Jay in that a car tire on the rear of the bike has no effect on the electric lean control.
I run a P205 60 on the Valkyrie. Not all car tires have the same profile. Some P205s will rub on the swing arm while others will not. Conversion tables are available to look up the difference in circumference for various car tire sizes to try to match the circumference of the car tire as closely as possible to the the motorcycle tire or you will have to calibrate the speedometer to adjust for distance traveled per revolution of the tire.
I have found the same to be true for fitment on the Valkyrie, some brands fit others do not. Why, motorcycle tires widths are rounded to the nearest 0, car tire to the nearest 5. So a 205 is give or take rounded to the nearest 205mm. Could be 197mm wide, 209mm depending on where ever the company decided to round from. And yes, I know in "math" there are rules for rounding, but that does not mean the rules are followed if the marketing people have a "better" idea. And of course anything manufactured has production tolerances such that two tires out of the same factory could be slightly different.
Jay G
DMC sidecars
Have found this tire size calculator very beneficial, though as said, sizes can vary some depending on the manufacturer.
https://www.tacomaworld.com/tirecalc?tires=90-90r21-110-90r19
Are there other tire size calculators out there that others use?
I went to a car tire on the rear of my '16 Harley Roadglide with a Hannigan Supersport hack and after about 8,000 miles I can report no significant difference in handling or effectivness of the Electric Camber Control (as Hannigan refers to it) vs the previous motorcycle tires. Of course, I'm mostly cruising and I don't push it to the limits of traction, though I do like to twist it up a little harder on twisty roads now and then.
