It is hard to find good information about darksiding online because of the strong emotions it involves. I've read a few of the threads on various forums in the wake of the Rider article. The zealots were crying that conspiricy, payoff and ignorance caused the article. I wouldn't mind seeing some actual testing performed, documented and reported. At a minium: acceleration, braking (wet and dry), slalom, and lap times (both racetrack and something like David Hough's PM Cornering Range). Preferably with similar bikes, or even the same bike with tire swaps. Ideally with multiple models - sport-touring, touring and cruiser, all with fresh tires. It might be difficult to find professional riders willing to push a darkside bike hard on the track or slalom, and it might be difficult to get insurance coverage for the event, but it would be a fascinating comparison.
In my opinion, the actual risk of darksiding is lower than the theoretical risk. From my observation of the riding skills, practices and habits of my fellow riders, I would doubt that darksiding adds significant risk. I would suggest that most of the risk that darksiders run, they carry inside. I feel the same way about ATGATT, or perhaps "non-ATGATT" would be the proper comparative term. Trying to briefly summarize my perception, I believe that the risk and severity of potential crashes are affected primarily by awareness, judgement and riding skills (DUI coming under the judgement umbrella), secondarily by vehicle maintenance, and last by protective gear. That is a rough summary, not a detailed risk chart.
I believe that a well-maintained darkside bike is safer that a poorly-maintained bike with hard, cracked and/or worn out bike tires. But I also believe that that is not a valid comparison. I also believe that darksiding increases the risks involved with riding, though not to the "you're going to crash and burn" strawman arguement level that darksiders seem to think is always used against them. My question is regarding the motivation to decrease handling and increase risk. It seems that the pro arguments come down to the following:
1. Decreased cost per mile. Car tires are cheaper and last longer.
2. Less rear brake lockup.
3. Better wet weather traction.
4. The handling is different, not worse. You get used to it.
5. We have actually done it. Your statements and facts are really just opinions because you haven't ridden thousands of miles with a car tire.
6. There are actually no engineering tests. The bike tire manufacturers are forcing their engineers to fake their engineering reports. The threaten bike publications and authors with loss of revenue were the truth to be told.
7. There are no records of crashes or deaths involving or caused by darksiding. It there were a problem, by now it would be all over the news.
8. For the way I ride, a car tire works fine / is sufficient.
9. The risks and reports of tires blowing off the rims are exaggerated.
10. There are more blow-outs on bike tires than car tires on heavily-loaded touring bikes.
11. I can drag pegs/boards/hardparts on my cruiser/tourer with a car tire. I don't need a bike tire.
I don't doubt that there are other persuasive arguments being used, but I do not recall them at the moment. In brief, I would respond as follows:
1. This appears to be reasonably true. Assuming DS reports are accurate, DS tire life exceeds curring touring bike tires.
2. I would like to see instrumented testing. These appear to be anecdotal claims which may well be evidence of poor braking skills and practice.
3. Again, instrumented testing would be helpful. Comparison testing under controlled or matching conditions could confirm or deny this claim.
4. Obviously, a rider can adapt to a poor-handling bike. Doing some back-to-back comparison testing with multiple riders would be much more revealing.
5. This is countered by the official responses of the pros, who build bikes and tires and test them. Not everyone has to experience stupidity to understand that it is stupid. Why should I risk life and limb to test what I believe to be a stupid idea? OTOH, limited closed course tests under controlled conditions are very reasonable. Bring your darkside bike to the range and let's run the tests.
6. These claims are barely worth a response. Easy to make, impossible to prove or refute. Not worth the time.
7. Similar to #6, but more and more DS crashes are being reported informally. Because many bike crashes are not reported to police or insurance, there is no record of DS involvement or cause. As there is no "car tire" box on the accident form, and because many/most emt's. police or other accident personnel are neither motorcyclists nor looking for car tires, there is very little likelihood of the DS involvement being reported, and even less chance of it being added to statistical reporting. On one of the DS forums, where they were discussing insurance and liabilty issues, a darksider reported that the car tire use was not observed nor included in the crash report. At this point, the lack of DS crash statistics is at least as likely to be a function of the lack of reporting rather than a dearth of crashes.
8. To me, that is one of the stronger arguments. It's your life, and your risk management decision. Odds are, you are going to get away with it, even if it's not a great idea.
9. This gets back to the bead and rim design differences between car and bike tires. The fact that any blow off at all is strong evidence that this may be a riding risk as well as an installation risk. Poor argument.
10. I found that one interesting. Whether true or not, it was apparent that some people to not make maintaining proper inflation of rear tires on touring bikes. At least one DS'er reported that he had experienced 4 blowouts with bike tires before switching to a car tire on the rear of his touring bike. I would tend to quote John Wayne on this one - Life is hard. It's really hard if you're stupid. Perhaps TPMS on heavy bikes is more than just a gadget.
11. At least semi-true. The max lean angle on many cruisers and tourers does not reach the edge of the tread on bike tires, and may not wear past the tread on a car tire. Again, it would be well to compare the lap times and observe the wear patterns after track testing.
I'd love to see some real testing. I will not run car tires on any of my motorcycles, barring disasters of Biblical proportions.
