Instructables
Going to the darkside, other than Star Wars, is the use of a "properly fitting" car tire, in place of the rear tire (most popular) or both front and back of a motorcycle. This is a documentation of my conversion process.

It is important at this stage to note that there are time and resources invested in this project for those who want to do this conversion on this model. If you don't have a metal lathe,  you will have to provide the necessary blue prints and money to assemble these parts with a rim other than OEM. These parts include a modified brake caliper hanger, different length spacers on the axle and a spacer underneath the 5 lug spline spider. The rim you need is 16" instead of the OEM 17" to faciliate a tire that will mount. The Goldwing rim is more narrow than OEM, these spacers and modifications aid the shift of the appropriate distance to the left so the wheel is centered.
abadfart5 months ago
Back to preparing for a dark side conversion on my yamaha royal star because I chew up tires with outrages amounts of chicken striping due to my sidecar sadly the venture has a 140/90r16 meaning the largest tire I can fit is a 155 but I can't find one for a 16" rim so I will have to fit a vmax 15" rim on the rear
Moddy (author)  abadfart5 months ago
I have 21k on this tire so if you can find a way to make it work, it will be worth the effort. Have you found a forum about converting what you have?
mscearce1 year ago
The previous owner did this to my Honda PC800. I do not like it, it makes the bike handle funny. Stops in a straight line great tho!
Moddy (author)  mscearce1 year ago
About a week ago, I was pulling up to a red light and there were uneven pavement, like a wake from a boat, except the bumps were parallel to the wheel. It can really throw the bike hard to the side. This can be the instant turn-off people are looking for. The allure is the challenge and not having to change a 150.00 rear tire every 8 or 9 thousand miles. I like the challenge above all and the cost savings second. I just turned 15k on my car tire today and have 1/4 of tread left. For longevity, there is no comparison. For personal taste, there is no end to the nuance or idiosyncrasy.
I don't care if you can do it; it's a bad idea to put a square-profiled car tire on a motorcycle. It is not safe.
abadfart2 years ago
very nice... iv been thinking of doing this ever since i moved to tubeless rims with my old cb650. now im on a vt1100 and looking at needing a new tire in a cople of months so i might make the change.
Moddy (author)  abadfart2 years ago
I am a conversion down a long line of people who have done it before me but not terribly many people have documented for my machine. In almost any forum for your ride there will be a die hard following for an auto tire. Especially for a cruiser. I have almost 5k on my machine and in less than 4 months. Putting those kind of miles on an MC tire keeps you busy putting new tires on. Mod
abadfart Moddy2 years ago
well this one will have to wait... my vt1100 is trashed and my doctor says its going to be a year or so before my leg will be up to ridding again
abadfart Moddy2 years ago
exactly i live in a tropical climate so there isn't a day that i cant ride so i dont own a car therefor i put alot of miles on my bike
kylemoe2 years ago
If you do this (and you shouldn't) be aware that if you are involved in an accident while using a non-approved tire, your insurance company can (and likely will) deny your claim.
Moddy (author) 2 years ago
This instructable is for the advanced motorcyclist seeking to do the mod. In time you will know who those individuals are by their comments.
More information can be found with a search engine for darksiding.
Quick-tune2 years ago
Perhaps you could tell us why you would want to fit a car tyre, You should also point out the dangers of using car tyres on a motorcycle which has no sidecar fitted. The handling is so badly affected particularly whilst cornering when the footprint of the tyre is greatly reduced. This is a bad idea on a standard roadbike.
l8nite2 years ago
I read this 3x, looked at the pictures several times and FINALLY figured out you were putting a car tire on a motorcycle.. Remember, just because you know what you're talking about others may not. Thank you for sharing