I also want to know the same thing. I use a 180-90 15 on my Honda VT1100 Shadow and would love to use acar tire. If you give us the name of thr dealer I will call and find out how he did it
Ron Campbell
Titan Engineering Works
Grand Junction Co
Evertthing sidecars
Here are the actual photos of the Firestone 165 SR 15 that was first installed by the Firestone dealer onto a Honda 15 inch MC rear wheel that blew up during installation. The dealer wisely refused to install a second but unwisely allowed the sidecarist to take a second identical Firestone 165SR15 to install. It also blewup during fitment and injured the sidecarists uncle quite severly during the process - believe it was a couple of busted ribs and a busted arm.
The subject of auto tires came up, at the tech session given by Crandall Weaver, at the 1992 National. A quite vocal sidecarist, in response to the
problem that "the auto tire is very hard to get to seat onto the motorcycle rim", had this to say: "No problem, just blow the heck outa the
tire. It will seat when inflated to 100 psi or more!"
The most hazardous (for your personal safety) time is when you try to mount these auto tires. The steel beads that make up the bead protection, are not rings of steel, but lengths of steel wire. They are held in place only by the stiction of the rubber to the steel. They are designed to be safe to the rated pressure of the tire, only, but they will usually hold in place if this pressure is increased by a few pounds. That means that if the tire is rated by the manufacturer to withstand 35 psi, that it certainly can withstand 35 psi, and may possibly stand 40 psi without damage. This certainly does not mean it can stand 80 or 100 psi as stated by our friend at the lead of this article.
I have also heard of other cases where the tires blew out on fitment. The tires that blew were not all the same brand, nor the same size. Blown tires included the 15SR145, the 155R155, and the 155R165. I have never heard of a 155R125 or a 15SR135 blowing out on installation, but these also should not be used except on an auto rim, or a rim configured to auto specs. At least I canna recommend this even though I will admit to having done so. Liability reasons.
That is why it is extremely important to find a foolproof method, if any, to find a way to mount a 15 inch auto tire to an unmodified MC rim. To date no one has come up with any method except to install an auto rim or to modify the MC rim to fit the auto specifications.
Once again, and for the record, the diameter of the auto rim is 14.968 inches for the 15 inch auto tire, while the diameter of the MC rim is 15.080 for the 15 inch MC tire.
And the diameter of the auto rim is 15.968 inches for the 16 inch auto tire, while the diameter of the MC rim is 15.968 for the 16 inch MC tire.
Now, do you see why there is no problem with 16 inch tires, but possibly a major problem with 15 inch tires?
Please take this situation up with the appropriate authority - the Tire and Rim Association who sets all the specifications for tires and rims on a world wide basis. Just google them.
Let's look at the facts.
* My rig has a 15" car tire.
* The rig has over 3,000 miles with the tire.
It appears that some outdated useless data was posted and we are all to believe this as gospel. The tire data was laughable and an embarrassment to hang ones hat on. What type of proof does one need to provide? It appears that it is easier for the majority to take the easy route and agree with the established hierarchy.
How many other opportunities to grow and move Sidecars forward have been lost? If we do not experiment and challenge the norm, progress will not be made.
To answer your questions. I am proud to challenge the status quo.
The only thing that I can say to you, is you must have a lot of built up carma. You are the ONLY person that I have hurd of that has not had a problem with 15" car tires on a bike rim and I have well over 60 yrs on a bike and MOST of them on a sidecar rig
Ron
It is obvious that you did not even bother to look at the photos of the new tires that exploded during fitment - you lucky dog. Yes, because your tire did not explode it does not not mean that Bill, or Tom, or Jim's tire will not explode. Yet you will not tell us what or how you fitted the tire different. The Tire & Rim Association - which has not changed the last fifty years, advises that the information given re tire and rim sizes, has not changed so it is you that is the laughable one. LOL. Was the tire out of specifications? Maybe. Was the rim out of specifications? Maybe. Did the installer use much more pressure than the maximum pressure stamped on the side of the sidewall which is a no-no and would weaken the tire and just not tell you about it? Maybe. Ride safe.
No offence to Hackellis, he's entitled to his own opinion, as long as he has the data/proof to back up his claim of a safe practice to mount a 15" automotive tire.
Honestly though, i don't see that proof. 1/8" difference in bead incompatabilities is a huge difference though, and the very fact of this difference puts me firmly in Hal's camp. I won't advise it, i won't recommend it, i won't even casually suggest it, because it IS bad practice to try to make something work that has been designed from the outset to be incompatable.
hackellis: Hal is not ganging up on you. He is questioning the veracity of your claims though, with good reasons .. and the reasons go way beyond you and your claimed success with a an un-modified 15" tire mounting. Hal has lived and breathed this issue, done his research, and consulted those in the industry who are directly in the know.
Personally, if it were me moderating, every post mentioning a car/motorcycle tire adaptation would have added in 20 point script "This is NOT safe practice!" .. note, i say all tire adaptations, not just the 15" 's - it's that big of a safety/liability issue.
Bill wrote:
"No offence to Hackellis, he's entitled to his own opinion, as long as he has the data/proof to back up his claim of a safe practice to mount a 15" automotive tire."
I think I had asked here (repeatedly) before for the alluded to 'new' data on this and it was never produced. The data we stand on was refered to as old and outdated. Well it is old but we need some proof that it is outdated.
NO...NO it is NOT good data for the masses just because someone has done it and got away with it. NOT AT ALL. As Hal mentioned, maybe the tire and wheel happened to be out of tolorance and all went together well. SO WHAT! This does not make it right. No one here wants to have the blood of anyone on their hands due to giving out wrong information on this.
If real data can be produced then so be it. If not the only responsible advice is to stay away from mounting 15" car tires on 15" motorcycle wheels..period.
Personally I hope the specs are, or were, changed as it would be a great benefit to many sidecarists to be able to mount a 15" car tire on a 15" motorcycle rim.
.
We need to get out and ride our rigs and quit the banter. Some of us may be to rapped up in being right at the expense of being blinded.
Lets get off our duffs and ride! I ride daily with my dangerous car tire and love it!
We do not want to be so blinded that we might be the cause of creating another with having a serious accident. We ask only that any who have made this extremely dangerous practice imform us exactly how it was done - ie -what was the maximum inflation pressure used - how exactly was this secret process performed and by whom? So far, all attempts to obtain this information from legitimate sources - such as professional and legitimate auto or MC tire installers have proven silent. All, as one, say - we will simply NOT do it under ANY circumstances. Those who have admitted to having done it have reported the auto tire blew up during the installation. Come on - we are waiting for the other side to present any factual evidence - names of the installers, where, who.
Ride safe. Or go get the auto rim to safely install the auto tire for the 15 inch auto tire.
I'm not taking sides on this issue - but obviously am following it since I'd love to put less costly car tires on my Suzi's 15" wheels. However, I can't help but wonder when those pics where taken of the blown Firestones? Could it be (1) they were taken many years ago and rubber formulas have improved since then? (2) They came from a "bad" batch of tires = ala Bridgestone from a feew years back? (3) The tires were old to begin with; i.e., had been sitting in a warehouse for ages?
Just wondering and realize that we probably don't have answers to these questions.
Sidecar Ron
A picture of some other riders with 15" car tires on 15" motorcycle rims. Open your eyes and quit following suit because of a few "want to dominate and control".
http://www.chromeheads.org/discus/messages/6/143819.html
MIke
Re the Firestone tires - those were from fresh stock - not old stock - at the time. However, they were designed to meet the identical specifications, sizewise, then, as the tires today. WE HAD EXTENSIVE CORRESPONDENCE WITH ALL PARTIES INVOLVED. True - tire properties might have changed. Also saw the photo of the rig with the 165-15 fitted. Looks nice. But again, no critical information as to HOW it was installed or by WHO or any way to follow up to obtain any valid information. Was the rim modified to fit? Some have done that. Just another in your face - well - here it is. I done it - now you risk it!
Ride safe.
A link to another fellow with a more detailed explanation. If you look through this fellows website you will soon discover that he is a technician.
http://www.parmidge.com/james.htm
How many more explanations, pictures do you need to stop saying you need proof? This is like insisting that the world is flat while Columbus was sailing around the world!
For some reason it does not matter how much proof that is sent, you have a closed mind.
Mike
Another nice try - he only stated that he did it - not how - which is the critical factor that noone will state or share. No one has ever said one has not done it. Did he modify his rear wheel? Not stated. What was his inflation pressure? Not stated. Will no one provide any details? Why the big secrets? I had a 15 inch auto tire on my Laverda - it used a Honda cast 15 rear. 135SR15. It slipped on at 45 psi with lots of rubber soap and a holding pattern of about 30 minutes before it popped. That is the MAXIMUM allowable pressure. The 125SR15s and the 135SR15s are not the problem. With care they will usually go on. It is the monster 165SR15s that we have the problems of the explosions. Those who have done it "safely" have an obligation to reveal their secrets - why are they silent? Potential liability perhaps?
Note - because I installed and drove with the 135SR15 on my rig, I still canna recommend that to anyone else. It is still a dangerous practice.
Drive safe.
I can't supply you any more proof on installation. I was there during the installation of the tire and was talking about my rig with the tire salesman. There was nothing out of the ordinary regarding the installation. There was no fear or anything out of the ordinary. The same goes for my car when I get tires. Never have I made notes and interviewed the installer regarding tire installation. I have attached a link of another installation of a car tire on a 15" rim.
http://www.chromeheads.org/discus/messages/6/217318.html?1140355604
It seems that I have provided indisputable evidence that a car tire can be put on a 15" motorcycle rim. A total of 5 successful installations were provided.
Did you know that dogs do bite their owners and cause serious injuries? Should we ban dogs? I can provide some statistics to prove my point? I don't think so. Anyone can use outdated data to support ones position. That is what is happening on this board.
Mike
