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Oh No - Not Tires

Contrary to your protestations to the contrary, you are being a compete jerk and snotty as hell. That's fine. It's one of the things that those of us who have been here a long time, have put up with time and again. We try our best to offer information BASED UPON FACTS, in order to help others here, and people like you come out of the chute, loaded for bear, filled with the most amazing and completely ill-conceived and asenine ideas which are actually dangerous as hell and can get somebody seriously hurt or killed.

You obviously understand nothing about the engineering principles nor the physics of why and how a motorcycle works. I know, to you, it's just a big bicycle with a motor or just a two-wheeled car. NEWS FLASH: It's neither.

Read and learn about the physics involved.

https://www.amazon.com/How-Why-Moto...coding=UTF8&psc=1&refRID=S1DDR36ACEM2R3W93QCK

and for a graduate level education I strongly suggest

https://www.amazon.com/Motorcycle-D..._rd_t=40701&psc=1&refRID=RKD0VGKANM0R1V58VNEV

If you want to hurt yourself, be my guest. I believe that people like you should be allowed to touch the proverbial stove until you burn yourself, because it is the only way you seem to learn however I will make a last ditch effort to offer an education to you, and perhaps prevent you from hurting some innocent person who cannot defend themselves from your foolishness, however I am sure you will reject all reason, science and logic in favor of your idiocy,

There are several good solid information sources out there about what you propose. Here is an excellent piece of technical information nevertheless.

https://www.goldwingfacts.com/forum...ferences-between-car-motorcycle-rim-tire.html
While I do appreciate the references that you cited, and will read them when I have time, I won't be calling you "snotty", or a "jerk". I retired from that type of thing about 50 years ago. If you would like to engage in civil discourse, that would be great.
I am not the first person to try this, so it is not totally uncharted waters. There are quite a few people who have done this for many thousands of miles. Have you spoken to any of them?
I guess it's a little bit like listening to an aeronautical engineer explain why bumble bees cannot fly, and then observing them fly with my own eyes.
 
While I do appreciate the references that you cited, and will read them when I have time, I won't be calling you "snotty", or a "jerk". I retired from that type of thing about 50 years ago. If you would like to engage in civil discourse, that would be great.
I am not the first person to try this, so it is not totally uncharted waters. There are quite a few people who have done this for many thousands of miles. Have you spoken to any of them?
I guess it's a little bit like listening to an aeronautical engineer explain why bumble bees cannot fly, and then observing them fly with my own eyes.

As I stated before, gutsy!

However, just because you can do something, doesn't mean that it's a good idea.

Other people may have gotten away with it, but there's just as high a likelihood that many did not. Coupled with that is the high probability of liability in the case of an accident. Worse yet, it's highly likely any insurance coverage would be invalidated.

Granted, most of us older riders took risks when we were younger. Hopefully we learned something as indicated by the fact that we're still around.

At the end of the day, what's being advocated here could get someone killed. Maybe not today or even a couple of years from now. But if that day comes, no one is going to care that two years elapsed without a problem. All they're going to care about is product misapplication.
 
I have no axe to grind either way as I've never even thought about fitting a car tire to a bike. Whether or not the solution "flys" isn't really the concern (but I would be interested to experience the result in a car park, just out of curiosity). Fact is, I would be more scared about the impact on my insurance. We all know (or suspect) that it doesn't take much for an insurance company to wriggle out of any claim they can and they'll sure wriggle harder if there's serious injury to a third party. Do you really want to fight that battle so you can save a few $$$'s on tires when the potential downside is "they take all your money and home and give it to them".

If the 3rd party sued because your insurance would not cough up, I strongly suspect it would be up to *you" to prove that your modifications to the bike did not contribute to the accident. From what I can read online that would be difficult (not to mention costly) when all the experts in the field, Engineers, manufacturers etc advise against it and it's acknowledged by everyone that's tried it, that fitting a car tire changes the handling of a bike in significant ways.

It's one thing to argue your case on a forum like this, quite something else to argue it in court in the face of expert opinions. Just because the courts are not full of such claims, doesn't mean they'll go easy on you, in fact I'm sure someone would relish the opportunity to set a precedent in just such a case - just saying, that's not something I would want to take on.
 
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First: I'm not a fan of the dark side because that is just me being me.

Second: Many Victory riders & quite a few Goldwing riders do run darkside & many of the the Vic riders are not slow riders & have logged enough miles to prove it to be safer than I would like to believe.

Third: Personally I would be more inclined to try it on my Vic than I would on any of my Guzzi's simply because of the characteristics of the bike. I think the darkside on a Guzzi is going to throw the handling off way more than on the Vic & the Vic is a great handling bike.

Each to his own, I'll stick with bike tires on bikes.
 
Contrary to your protestations to the contrary, you are being a compete jerk and snotty as hell. That's fine. It's one of the things that those of us who have been here a long time, have put up with time and again. We try our best to offer information BASED UPON FACTS, in order to help others here, and people like you come out of the chute, loaded for bear, filled with the most amazing and completely ill-conceived and asenine ideas which are actually dangerous as hell and can get somebody seriously hurt or killed.

You obviously understand nothing about the engineering principles nor the physics of why and how a motorcycle works. I know, to you, it's just a big bicycle with a motor or just a two-wheeled car. NEWS FLASH: It's neither.

Read and learn about the physics involved.

https://www.amazon.com/How-Why-Moto...coding=UTF8&psc=1&refRID=S1DDR36ACEM2R3W93QCK

and for a graduate level education I strongly suggest

https://www.amazon.com/Motorcycle-D..._rd_t=40701&psc=1&refRID=RKD0VGKANM0R1V58VNEV

If you want to hurt yourself, be my guest. I believe that people like you should be allowed to touch the proverbial stove until you burn yourself, because it is the only way you seem to learn however I will make a last ditch effort to offer an education to you, and perhaps prevent you from hurting some innocent person who cannot defend themselves from your foolishness, however I am sure you will reject all reason, science and logic in favor of your idiocy,

There are several good solid information sources out there about what you propose. Here is an excellent piece of technical information nevertheless.

https://www.goldwingfacts.com/forum...ferences-between-car-motorcycle-rim-tire.html

Excellent information. Very detailed. Some of it I knew and some of it i was suspicious about, my gut always has said "don't go to the dark side." To paraphrase Dr. Ian Malcolm; "The dark siders always seem so preoccupied with whether they can, they never stop to think about whether they should."
Can and should are often two very different animals...I will stick with my Avon's...in the factory sizes.
Ride Safe
Kirk
 
How many miles did you ride on one before coming to your apocalyptic conclusion? Or, how many other riders did you speak to who have ridden on one?
Sincerely asking, because all of the people that I have found who are totally against it are the ones who have never tried it. I have yet to hear of anyone crashing due to the fact that they were using a car tire. If you know of some, please let me know (with references, so I can read about it myself).
Not trying to be a jerk here, but I heard all of the reasons why it shouldn't work, and on the other hand, I have heard of many people who do it with no problems. The worst thing that I have heard from people who have tried it is that it takes some getting used to do to the flat profile. Some are fine with that, and others hate it.
I will give an honest report after I get it installed, and put a few miles on it. If I find that it is not for me, I will say so.

While I do appreciate the references that you cited, and will read them when I have time, I won't be calling you "snotty", or a "jerk". I retired from that type of thing about 50 years ago. If you would like to engage in civil discourse, that would be great.
I am not the first person to try this, so it is not totally uncharted waters. There are quite a few people who have done this for many thousands of miles. Have you spoken to any of them?
I guess it's a little bit like listening to an aeronautical engineer explain why bumble bees cannot fly, and then observing them fly with my own eyes.

Actually James, you didn't retire from it, you just got better at doing it backhandly. Your original post drips of snideness, innuendo, anecdotal gibberish, and your pinnacle statement that you will give an "honest report", thereby insinuating that anybody who disagrees with you and your anecdotal evidence, is being dishonest. (I bolded and underlined your comments which I clearly felt were snotty and being a jerk. Perhaps you might want to re-read them.

Your "never tried it" argument takes the cake though. I don't shoot heroin, do you know why? I don't have to "try it" to know it's a bad idea. I can examine the facts and scientific evidence and formulate a logical, rational conclusion.

So, the bottom line here regarding car tires on motorcycles is I don't "think" I know what I am taking about here. I know precisely what I am talking about, forwards and backwards. Given that, I don't pull punches. When you are dead ass wrong, I will say so, especially if what you are suggesting is tantamount to giving stupid, suicidal advice. I love this forum and feel that we have a responsibility to not give people information that can endanger their or others lives.

To that end, James, you're dead ass wrong here! Dangerously so, and I will not let you get away with it unchallenged.

This is not about "the dark side" nor is it about bumble bees. It's about utter stupidity compounded with being completely ignorant of the engineering behind motorcycles and specifically motorcycle wheels, tires, and handling characteristics, and then suggesting that simply because others have been fucking stupid, it's okay to be fucking stupid too! Are you kidding me?

Did it ever occur to you that the overwhelming majority of motor-vehicle accidents resulting in a serious debilitating injury or death, are never analyzed in more than a superficial manner. No detailed inquiries are made into equipment specifications as a matter of normal police reporting of most fatalities. It makes sense that you aren't going to read about it. Besides, it's anecdotal.

I'll stick with engineering, physics, and math; all three of these disciplines are in direct opposition to what you are proposing.

I'm glad you'll read the info I gave you "when you have the time". Good for you. I suggest you pay strict attention to the sections about how the rims on a motorcycle have a completely different sealing lip profile than a car rim, as well as motorcycle tires sidewall seal profile versus car tires.

But then again, I'm quite convinced that you will never educate yourself on this topic. Your cup is already full of the bullshit Kool-Aid you've been drinking and continue to drink on this topic.

I'm done here.

“It is unsafe to install passenger tires on motorcycle rims. Motorcycle tires and corresponding motorcycle rims (typically marked with “M/C” and/or “MT”) are designed with a different bead seat diameter and flange contour than passenger car tires/rims. Consequently, any attempt to mount a passenger car tire on a motorcycle rim may cause inflation pressure loss or the beads to break with explosive force resulting in possible serious physical injury or death.”
(Rubber Manufacturers Association, Tire Information Service Bulletin, Vol. 28, No. 3, 2012.)"
 
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Scott, sorry that I seem to have upset you so badly.
I have not recommended that anyone else try this. You seem to be the one who has made up his mind, and apparently are not at all interested in honestly examining the experiences of people on the other side of this topic.
Furthermore, all I meant when I said that I will give an honest report, is that I will not pretend that I am happy with the change, if I really am not. I would not have too much pride to admit that I do not like the change, if that turns out to be the case.

I did not sign up here to argue with people, or try to tell others what to do.
I really enjoy reading the posts on here from others who own bikes like mine, as we really are a tiny percentage of the motorcycling community.
 
Unfortunately, you're still missing the point by your statement, "...apparently are not at all interested in honestly examining the experiences of people on the other side of this topic." Really?

Scott's heroin analogy is spot on. The vast body of evidence would indicate that this a "shallow end of the gene pool" thing to do.

The other side of this, and this is the rather maddening aspect, is that if someone ends up hurt, disabled, or dead there's a reasonable probability of a lawsuit. Why? Because a 16" car tire was able to be mounted on a 16" motorcycle rim, the motorcycle manual didn't say not to mount car tires on a motorcycle, etc. The list of possibilities is endless.

In the end, all of us end up paying for ill advised "experiments" like this. And, unfortunately, it does nothing to advance the cause of the motorcycling community.
 
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Guys, easy here. If people want to experiment, they will at their own risk/peril.
The grand poobah of the MGNOC has run many a rear car tire on his 1400, but he lives in Kansas.
No need to go to battle here on this.
 
So, lemme get this straight. You've had guys put a set of Michelin Commander II's in 180/65/16 on the rear with good results? No need for recalibration of anything? (forget speedo, who cares). And the only difficulty was in getting the thinner tire to bead on the rim? Will my ape mechanic be able to do it? I've got Metzeler marathons on, I replaced the stock with -- they're not much better. Grip is meh and already at less than 4K miles they're showing decent wear..........I know this bike can handle, but it needs a set of tires capable of pulling the 'sport' out of this sport cruiser.............

My wife and I have worn through the factory Dunlops and 2 sets of the Metzler 880s through a lot of hard touring. I got about 6K out of this last 880 Rear before it was fairly squared off. Still has a little life in it but we're heading from Indianapolis to Colorado and then north to Wyoming and back at the end of the month and I've got a Michelin Commander II 180/65/16 on order and will have it mounted later this week.

I'll post my pics and thoughts afterwards. As for recalibration. With how much these other tires have worn square I doubt that I'll notice a difference in the Michelin due to circumference.

I've got no front tire complaints right now. I put an avon cobra on it about 3.5K miles ago and it looks good. I did notice some possible balance vibration on the last trip out west but I think I'll probably pull off the wheel and have the balance properly checked before leaving on this next one.

And just to keep things light :) here's a picture of the guzzi doing proper load balancing with proper loads up in the Adirondacks ;)

Cheers, Joe

IMG 0550
 
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My wife and I have worn through the factory Dunlops and 2 sets of the Metzler 880s through a lot of hard touring. I got about 6K out of this last 880 Rear before it was fairly squared off. Still has a little life in it but we're heading from Indianapolis to Colorado and then north to Wyoming and back at the end of the month and I've got a Michelin Commander II 180/65/16 on order and will have it mounted later this week.

I'll post my pics and thoughts afterwards. As for recalibration. With how much these other tires have worn square I doubt that I'll notice a difference in the Michelin due to circumference.

I've got no front tire complaints right now. I put an avon cobra on it about 3.5K miles ago and it looks good. I did notice some possible balance vibration on the last trip out west but I think I'll probably pull off the wheel and have the balance properly checked before leaving on this next one.

And just to keep things light :) here's a picture of the guzzi doing proper load balancing with proper loads up in the Adirondacks ;)

Cheers, Joe

View attachment 15228
Nice looking bike. Is that a stock touring seat, or the custom seat? Hard for me to tell from the angle of that photo. And, what passenger backrest is that?
My wife does not like the stock seat on my California Custom, and I think that a backrest might make her more comfortable.
Thanks, James
 
Nice looking bike. Is that a stock touring seat, or the custom seat? Hard for me to tell from the angle of that photo. And, what passenger backrest is that?
My wife does not like the stock seat on my California Custom, and I think that a backrest might make her more comfortable.
Thanks, James

My bike is actually a 2014 custom (purchased in Feb. 2015) and I added the saddle bags, Touring Seat, and windshield right from the get go. The seat is from the red model touring that came in 2015 if I remember correctly. I still have the original custom seat, but the wife doesn't like riding on it :)

The backrest is a Hepco Becker w/luggage rack. When touring we have a rack extender to give a flatter/larger surface for a duffel bag. I think its a hepco becker as well.

Cheers, Joe
 
Apologies.

Without going into the details, yes, I am incredibly passionate about this topic and why I initially implored you not to do this.

It is because when I worked at BMW Motorcycles, one of my favorite customers was killed when his rear mounted car tire, suddenly and unexpectedly lost sealing on the K1200LT motorcycle rim on S6 - Mt. Palomar. In an instant, he lost control and went head-on into the oncoming truck and was killed instantly.

I'm sorry I said anything at all.
 
Apologies.

Without going into the details, yes, I am incredibly passionate about this topic and why I initially implored you not to do this.

It is because when I worked at BMW Motorcycles, one of my favorite customers was killed when his rear mounted car tire, suddenly and unexpectedly lost sealing on the K1200LT motorcycle rim on S6 - Mt. Palomar. In an instant, he lost control and went head-on into the oncoming truck and was killed instantly.

I'm sorry I said anything at all.
I am very sorry that you lost a friend that way.
As painful as it may be to talk or write about, that is the type of information that I am seeking. I really do want to hear both sides of this issue.
Up to this point, I had never heard of a case of someone actually having a catastrophic failure due to using a car tire.
Thanks for explaining why you feel so strongly about this.
 
My bike is actually a 2014 custom (purchased in Feb. 2015) and I added the saddle bags, Touring Seat, and windshield right from the get go. The seat is from the red model touring that came in 2015 if I remember correctly. I still have the original custom seat, but the wife doesn't like riding on it :)

The backrest is a Hepco Becker w/luggage rack. When touring we have a rack extender to give a flatter/larger surface for a duffel bag. I think its a hepco becker as well.

Cheers, Joe
Thanks for the reply.
My bike is set up very similar to yours. I bought mine used, and it has a small rack on it that I think is a Moto Guzzi part(not sure). I would like to get a touring seat, to see if the little woman likes it better. However, I am a cheapskate :) so I am not willing to spend much, only to find that she doesn't like that one either.
 
Apologies.

Without going into the details, yes, I am incredibly passionate about this topic and why I initially implored you not to do this.

It is because when I worked at BMW Motorcycles, one of my favorite customers was killed when his rear mounted car tire, suddenly and unexpectedly lost sealing on the K1200LT motorcycle rim on S6 - Mt. Palomar. In an instant, he lost control and went head-on into the oncoming truck and was killed instantly.

I'm sorry I said anything at all.
Scott, don’t be sorry. Those are important details to post. I personally would never do it, and the reason you state drives that point home further.
 
I got the Michelin Commander II 180/65-16 mounted to the rear yesterday. The shop had no issues seating the bead. I was a little worried on how it would look on the bike as there was quite a noticeable difference in size if you had the two tires sitting right next to each other. However I think it looks good on the bike and the first short ride proved to have nice handling, though I had to take it a little easy until I break in the tire. Also replaced the Pads all the way around so bedding those in.

Posting pictures for reference as I don't think I've seen any that give a good rear and side profile of the Michelin. The front tire is a AV71 in stock size.

Doing a long road trip at the end of the month...cant wait to see how it holds up fully loaded with passenger.

Cheers, Joe

IMG 1091

IMG 1093
 
Just home from a roadtrip of 7900 km. ,fully loaded with passenger. With my previous michelin commander, i drove 16.000 km. Grtz Rudy
Sardini
 
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