The darkside, car tire on motorcycles

Discussion in 'The Perfect Line and Other Riding Myths' started by elkgrichard, Sep 19, 2014.

  1. liberpolly

    liberpolly Nu, shoyn, nudnick!

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    Let’s start with the way the darksiders start foaming at the mouth and curse incoherently when asked a simple question.
  2. Jarlaxle

    Jarlaxle Bregan D'Aerthe

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    If you have these hallucinations regularly, see a doctor.
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  3. LAFS

    LAFS Long timer

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    Kinda funny as I dark sided my RT for many miles chasing a GS with a very experienced rider and never slowed him down. This is South Central PA and we have some of the best riding around. The only "bad" thing about a car tire and handling is it will follow road ruts and drop in and out of them noticeably. Other then that I scraped my peg feelers on that car tire and it never gave me any issues.

    I still have the rim, tire, and the spacer and longer bolts.

    The only bad thing I can say is if the tire gets too low it will leak along the bead. If you break the bead somehow like a pothole the tire is going to go flat and it is going to walk around that rim. Now any blow out will do that to a point but in this case there is NO HOPE of the tire staying on the bead at all as the only thing holding the bead is air pressure there is no drop in or lip that matches the car tire as it's bead is COMPLETELY different. A motorcycle tire with 15 pounds of air in it will roll, a car tire will not as the bead is broken and the tire is spinning on the rim at the 15 lb of air mark.

    As I said I rode the hell out of it and never gave it a thought after I got used to how it rolled over in a corner. If you watch the videos available you will in fact see a car tire rolled over has so much more contact patch then a motorcycle tire could ever have. It is out there to see and watch with your own eyes.

    Gold Wings been running them for 100's of thousand miles and I have never seen or read an issue. FJR 1300's have run them, Harley's have run them and probably so many more.

    That said it is YOUR choice so go for it.
  4. glory racing

    glory racing Been here awhile

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    So,,,What you have read some other darksiders say is the extent of your experience? You were originally asked a simple question now how bout a simple answer.
  5. inverted

    inverted Berwyn rocks

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    you're asking for something he cannot give.
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  6. davidji

    davidji bike curious

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    Are dark side riders able to do plug & inflate roadside flat repairs? Are they able to get the bead seated with mini compressor, mini bicycle pump, or whatever inflator they have with them?
  7. Cat0020

    Cat0020 El cheapo

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    I've plugged a car tire roadside on my Burgman 650, after riding it nearly flat for over 20 miles on the NJ Tnpk at highway speed.
    Bike felt sluggish, but no other significant handling problem.
    Bead didn't come off the seat, plugged and inflate with gas station air compressor to 40 psi.; rode it home for another 70 miles without stop.
    Put another 10k on the plugged car tire.. still riding it to this day.
  8. glory racing

    glory racing Been here awhile

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    Nope, they will explode and burst into flames!
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  9. Davidprej

    Davidprej Davidprej Supporter

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    Funny, but it was a legit question and no one has answered it yet. I'm new to CT, so haven't had to test his hypothesis yet.
  10. glory racing

    glory racing Been here awhile

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    Sorry, couldn't resist. I have not had to do a repair roadside so have no direct experience. But when mounting, I have done 3 now, setting the bead is no different than a moto tire. I have no concerns my little 12v Slime pump will handle the job.
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  11. c_m_shooter

    c_m_shooter Ninja Warrior Supporter

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    I followed a guy running a car tire on an FJR through Deals Gap. It turned just fine. I was one of the people who doubted it until a saw it with my own eyes.
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  12. phughes

    phughes Long timer

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    Sure they do, for many, many thousands of miles. Had one, did that. As log as you buy tires from a good manufacturer, rated for the task, you are fine. If you cheap out and buy a tire not made for the task, then your fault. Tire pressure is important as well. In over 150,000 miles, I have never had a tire fail. I also never saw a Goldwing tire fail when working at a Honda dealership. I did see many abused Goldwing tires come in, many down to the cords. A tire is only as good as the idiot on the bike. That person has to actually take care of the tires.

    The point of my post was, that anti-darksiders complain when darksiders use anecdotal evidence, and tout empirical evidence, and the person I responded to used only an opinion not based on anything but his own thoughts, and possibly anecdotal evidence. It was amusing, and incorrect.
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  13. LAFS

    LAFS Long timer

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    Well that is the thing the bead does not seat, it seals but it does not seat as totally different lip on a motorcycle rim and a car tire rim. I do not know about the plug but I assume as in that way a tire is a tire but again you have more bands in a car tire just due to size but you should be able to plug it no issue. It only runs at 28 PSI or so, so yes a inflation device would do it but again I have no personal experience with a flat when I dark sided.
  14. foxtrapper

    foxtrapper Long timer

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    I think you're the first darksider I've ever heard talking about walking the tire bead off the rim. I agree, the rim profiles are different, but I wouldn't call them completely different. Picture attached below for clarity for folk following along.

    [​IMG]

    I agree, they are different. But I don't see anything that prevents the car tire bead from seating down into the valley. As far as I know, the tire wire bead is the same diameter for a given tire diameter, car or motorcycle. The pictures I've seen of car tires taken off after use on a motorcycle rim show the tire making full contact with the rim. The right hand images in the picture above would be fully accurate if the tire was made of rigid material. But being rubber, it deforms, and pulls down into that grove.

    That said, I'm not arguing with you experiences of having a bead walk off. I'm curious about more details of that. You had mentioned 15 psi which seems very low. But then I've run highway tires down as low at 2 psi on some motorcycle trailers, just to get sidewall deflection over bumps and to stop the trailer from bouncing around. Never had a problem with one of those tires coming off the bead. Yes, I've blown many tires. Yes, I've had blown tires sometimes off the bead. In fact I've had some come completely off the rim.

    If you'd be willing, I'd really like to hear more from you about losing the bead with a car tire, and the low pressures you mentioned. For I suspect there's some interesting information in your situation and experience.
  15. LAFS

    LAFS Long timer

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    Well all you have to do is take the wheel off the bike and keep dropping pressure and somewhere around 15 lbs or less you can push the sidewall down. You also pour water around the bead and release air until you see it bubble. I dropped pressure on a car tire on the changer that had been run 6000 miles or so. Like I say as soon as the pressure dropped low I could push both side walls off and into the center. You CAN NOT do that on a motorcycle tire with 6000 miles.

    The lower right hand diagram shows you exactly what you are saying is a bead. That left hand side is not even close to a bead. The top also shows that you have a very small contact surface on the rim with a car tire. Look at that. Figure out the % of contact between those two beads. Like I say not my monkey not my circus.

    Again I am not here to debate this with you or say it is right or wrong. I did it, wore that t shirt, and am done with it.

    We all assume our on level of risk, as I get older I want to lessen that amount of risk in EVERYTHING I do.

    I quit smoking 9 years ago, lost 50 pounds, exercise as best I can without the gym, and stay as active for a busted up old man as I can. I wear a airbag vest, ATGATT, and do my own maintenance except tires. I used to spoon them on and off but got to be too much after the accident in 2010.

    So if I am doing what I can to stay alive and draw my retirement as long as I can, running a car tire on a motorcycle rim is not doing the best I can to mitigate risk.
  16. Cat0020

    Cat0020 El cheapo

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    Tire rubber is flexible, conforms to the rim even if it's not inflated.
    No tire is going to match rim profile 100% without the tire rubber at the bead flexing in shape.
    Air pressure in tire help to seat the bead & shape the bead rubber to seal.
    Once the bead is seated, the rubber will conform to the share of the rim 100% with flex even at low tire pressure.
    Cutaway diagrams are inaccurate representation of actual tire mounted and seated on a rim.
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  17. windmill

    windmill Long timer

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    But at the same time, those who do have experience, and are currently using car profile tires, but don't think they're all puppies and rainbows get dismissed, or degraded the same as the inexperienced naysayers.
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  18. glory racing

    glory racing Been here awhile

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    The quoted message was addressing one particular posting based on previous comments. Your post is accusing all and is inaccurate. If someone with actual experience doesn't like a car tire...so be it. No different than if they don't like a Dunlop or whatever moto tire. Your comment is not true of the majority.
  19. foxtrapper

    foxtrapper Long timer

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    Interesting! Makes me wonder if that’s more to do that particular rim, or perhaps the specific tire. There are standards, but there is also slop in those standards. A large part of the reason some tires seat easily, and some don’t.

    Thanks for the additional info you provided!
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  20. windmill

    windmill Long timer

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    You just proved my point. My experiences have drawn criticism, and now I get criticism for pointing it out. Like with some other debated aspects of riding, some proponents are very intolerant pragmatism.