JJ wrote:I own a 2003 Suzuki LC1500 and I was wondering what experience if any anyone has with using a car tire on the back wheel.
It seems anyone who has done this extolls the virture of mounting a car tire with only minor degradation of handling at low speeds.
People say they have to relearn the leaning thing (be a bit more forceful and telling the bike to lean, not just letting it lean)
So I know a lot of people will want to warn against this. OK I hear you. I want to hear from car tire users first hand
Jan
Hi Jan,
Your post is pretty typical when anyone asks about using a car tire on a motorcycle on motorcycle forums, except that in many other forums you will get some first hand information from people that have tried it, but mostly you find really negative posts from people who have never heard of it or just can't seem to wrap their heads around the idea. The practice of running an appropriate car tire on a large motorcycle is referred to as "Going to the Dark Side" by those who do it, there are many web forums where you can get information if you look up "Motorcycle Darkside" on Google. This has been done very successfully for many years by thousands of people riding large cruiser or touring motorcycles. I doubt if you will ever hear anyone recommend trying this on smaller cruisers or sport bikes of any kind because these bikes need the features of motorcycle tires for safety. But on big bikes, such as the Goldwing, Valkyrie, Rocket Three or big metric cruisers like my Vulcan 2000, that never approach the lean angles of sport bikes, car tires have been proven in real world use to be a good alternative. It's a bit like taking Pirelli P-Zeros off a Ferrari and running them on subcompact car. They may be arguably better tires than the subcompact tires but they do not add anything to the performance or safety of the subcompact and they will never even approach the level of performance they are capable of while used on the subcompact.
When my wife suggested we get a bike to ride together and after some research we decided on a Vulcan 2000. With a bike that weighs over 800 lbs. combined with the weight of my wife and I (I'm 270 lbs.), we exceeded the suggested weight limit for the OEM motorcycle tire that came on the bike. I became very concerned about overloading the motorcycle tire and started to research safer tires. That's when started reading in some detail about the many people running car tires on bikes like mine, big, heavy cruisers and touring bikes. I' had heard about people doing this for many years and my reaction was "Wow, this really sounds like a bad idea!" until I did some research.
There are thousands of people that have many years and miles of experience running car tires on big bikes and they are nice enough to share their experiences on several different motorcycle forums. While I will not risk the safety of my wife or myself based just on some half baked sounding idea on motorcycle forums, I also will not ignore the overwhelmingly positive reports from virtually everyone that has done it. Also, there are many people, who probably mean well, that will post their opinions that this idea could never work and you will die a fiery and horrible death if you try it. I have never seen even one example of anyone having, or even knowing of anyone having, a bad or unsafe experience using a car tire. I would expect that if anyone could produce such a story, especially those who condemn the practice, they would be glad to share it.
I decided to do my own research on the subject and have found that almost every negative point discussed is based on misconceptions, misinformation and "common wisdom" that turns out to be completely wrong. Look at some of the statements in this thread for example. "Cars tires last longer because they have deeper rubber tread and its a harder compound. This harder compound to last longer but will not grip as well. the car tire is not designed to rotate like a proper bike tire and will have a smaller contact pack in the corner with a less grip. turning will be screwed."
Almost nothing about this statement is factual. My personal experience over the years with my "thumbnail durometer" has always shown motorcycle tires to have harder rubber compounds than car tires. I have understood that they need harder rubber to withstand the high pressures that result from a very small contact patch as compared to car tires. But after hearing so many people on forums state for a fact that motorcycle tires are softer than car tires I did some internet research to satisfy for myself the truth. I found that, in similar performance categories, motorcycle tires have a 10 -15 point higher durometer number than car tires. The Bridgestone Battlax that came on my Vulcan 2000 has a durometer number of 70, the high performance Battlax for Sport Bikes has a durometer number of 65. Durometer testing of eight 60,000 mile rated car tires showed a durometer number of 65. The Dunlop SP 5000 symmetrical car tire I have selected has a durometer number of 50. Many ultra high performance street car tires have durometer numbers in the 40s and 50s. After much discussion on other forums, no one has ever presented any data that refutes the fact that, in general, motorcycle tires are made of harder rubber compounds than car tires. So anyone willing to check the facts will find that car tires actually have "grippier" rubber than motorcycle tires. Also, the claim that a car tire will have a smaller contact patch has been shown to be false, the opposite is true as car tires will have a much larger contact patch than a motorcycle tire at the lean angles generated by big cruiser type motorcycles. I really advise taking a look at this link to the Motorcycle Tips and Techniques safety forum hosted by James R. Davis, a pretty well respected expert on motorcycle safety.
http://www.msgroup.org/forums/mtt/topic ... IC_ID=1784
While at no time does Mr. Davis recommend putting a car tire on a motorcycle to anyone. He approaches the subject with an open mind and explains why there might be some advantages that would make him consider trying it. Even though he also claims that motorcycles tires have softer rubber than car tires, this seems to be a widely held misconception that I do not feel discounts his opinion. I have satisfied myself, based on durometer readings from many sources, that the relative rubber hardness is in fact a misconception. I also would never recommend that anyone try this. I would never have considered doing so if I did not take the time to some research and determine what the real facts are. Many people do this for economy of for looks, neither of those reasons have any sway with me. I was looking for safety and feel the car tire will provide the best load rating, braking, wet weather handling, ride comfort, cornering grip, high speed stability, etc. In addition I will get the extra benefits of much higher mileage, lower initial cost, lower cost from fewer installations, less down time, etc.
As for your question about wanting to hear from people with actual experience, here is a link where you can read about some first hand experiences:
http://mcdarksiders.forumotion.com/ There are many other forums to get good information from.
Good Luck
