Are Motorcycle Tires a Ripoff? The Darkside Car Tire Experiment 

"Spontaneous uninstallation." That's almost as good as rapid unplanned disassembly.

"we're motorcyclists, masters of measured risk" Now that's a decent compliment

Okay, I don't know how I've never seen the kickstand bead break before, but that is way more value than I was expecting from a video about a terrible idea!

So, either Ryan is into something illegal or he legitimately uses a flip phone.

It’s almost as if car tyres and motorcycle tyres were specifically optimised for their respective applications

The quality of the production is so good that i feel guilty for watching it on RU-vid.

I came into this thinking that darksiding is a terrible idea. I still do. Thanks for another great video!

Where I think this could be worthwhile would be on a sidecar combination. They're not supposed to lean into turns, so the square profile isn't a problem and in fact gives you a larger "footprint".

5:36 "Car tyre fits a motorcycle like I fit a bikini. Humps and curves in the wrong places" 😂😂😂

I've ridden darkside. I actually rode Darkside for over 5K miles, before lowsiding it in a curve one day. The handling characteristics are truly shit. That car tire will follow the contour of the road. I was riding interstate 200 miles a day, which is one reason I made it so many miles before crashing. Let me tell you, Darkside on the interstate is like sitting on the sofa, it is so smooth. It wants to stand straight up, allowing me to cross the entire Dauphin Island bridge with out touching the handlebars. On the other hand, i ran through some tiny pebbles in a curve one evening too fast. I had to "force" the bike to lean far enough, so far, in fact that the asphalt contacted my rear saddlebag, taking the weight off the wheel. I corrected by steering back toward the center of the road, that's when the tire got in its happy spot , back on the tread, going into the old "death wobble". During the extreme leaning, the engine guard had contacted the asphalt and wrapped around my right ankle, rendering me helpless as far as using the rear brake pedal. Long story short, i now can't kick the bike away from me, I'm attached by the ankle, lowsiding on the left side of the road between two street sign posts. That's when bike and I both went over the embankment, still attached to the 700lb beast. She flipped mid-air and flung me off. Came out out of that with three broken toes, and the toe burned off my right boot, oh, and a totaled bike. No more Darkside for me.

I have to say FortNine has kicked up the production value of it's videos, and I like it. The editing, videography, audio quality, dialog are all spot on. He could be talking about pants and it would be entertaining. The fact that it's about motorcycles is just a bonus. Keep up the awesome work!

Hahaha 2:37 sign of the cross… legit do this anytime I’m about to attempt something sketchy 🤣

I appreciate 1. the flip phone 2. that your first ride was in the rain with just 'jeans' and not $1.2 million in Klim ultra armor 3. the flip phone 4. your willingness to work on a bike in hipster boots 5. the flip phone

Putting a car tire in the back wheel makes it look straight out of a Hot Wheel bike lmao.

Not only did he use a car tire but a fairly modern one at that with Asymmetrical treads on it man has guts

I've darksided a GL for the life a tire, mostly through a very rainy winter in Portland, OR... it was good in snow, it was good in the rain, and it was good for towing a trailer. The tire didn't last much longer than an regular motorcycle tire, in a large part as I spend a lot of time on the sidewall. (I used to own and now occasionally teach for the Northwest Motorcycle School, where we taught a motor officer course to the general public, and much of our riding was full lock, full lean and below walking speed.) I simply wore the shoulders of the tire out, while the center tread was fine. I'm not teaching regularly now, and living in New Mexico, with it's mostly straight roads, I spend far less time on the tire's shoulder. I was looking into another darkside tire, when I noticed the weight difference. A car tire for the GL weighs between 9 and 11 Kg. (20-25lbs), while the motorcycle tires weigh around 3 Kg (according to manufacturers). That terminated my search, the durability might be great, but the added, un-sprung weight kills suspension response, and may have been a good portion of why handling "sucks." Yes, the bike understeers with the car tire, but, as noted in the video, it takes about 10 minutes to get used to keeping pressure on the bar while cornering. However, the tire's following of rough roads is severely compromised, particularly when leaned over. Just one more element to consider.

Dear God; he's even doing this in wet conditions....

As soon as I saw thr zip ties come out, I was like "you're crazy". Seeing the flip phone confirmed that. Lol

My 2006 Rocket III Classic was a great riding & handling bike with a 225/50R-16 Dunlop Direzza DZ101. Perfect match in all dimensions to the stock Metzler 240/50-16. The sidewall had the same rigidity, identical overall height and width, and it was a sticky performance tire. The tread was a sporty symmetrical & directional pattern with a rounded edge. I ran at about 25psi which resulted in smooth, stable, composed handling and MASSIVE traction advantage over the MT. The bead did not look any different than the Metzler either but I was not using a run-flat. I installed and balanced it myself. Trust me, the size & weight of that rim with brake rotor far exceeded any worries of unsprung weight. And yet, the Dunlop was fairly light as well. I had no vibes or gyroscopic tendencies at any speed. My bike would top out about 135mph - limited by the windshield, floorboards, and bags (and my fat butt). I scraped the boards frequently (thankfully they articulated). If blindfolded, one would only know it was a CT at walking speeds. Above that it was almost unnoticeable. Yes, a bit more counter steer was needed to initiate a lean but by the end of the first day riding you did it subconsciously. Grooved road surfaces didn't affect it much but I think that depends on the tread, pressure, and width mounted on each bike. For my bike/tire combo, it was well behaved, confidence inspiring, and FUN to drop clutch and peel out. No more applying throttle timidly while turning for fear of losing the rear. Nope. pour it on and leave a beautiful black arc behind. But before I have rotten vegetables heaved my way, yes, there are some drawbacks and you need to gauge your abilities. If you have even the slightest doubt, then by all means don't do it. Those of us who darkside don't just throw any POS tire on there. #1 - Darkside is not for all bikes. The GS is probably not the ideal candidate being so tall and narrow. Best left to heavy, lower, tire grinders like Power cruisers & touring bikes. #2 - Narrow rim & wide tire are not a good combination. DS works better on a wide rimmed bike. In this test a narrower tire (if even possible with the given wheel) would have produced better results. #3 - Tire pressure looked high and gave the impression the handling looked edgy. Inflation is key to good tread/sidewall compliance. Regardless, I thoroughly enjoyed the video and would say almost everything he said was correct.

That sign of the cross just before riding the thing killed me

When you find yourself going faster than you should be in a long, sweeping corner, MC tires seem like a real bargain.

I like the center stand bead breaking! Genius!

Great video, interesting topic. My take on it.... I would never be a mooch and try to save a few dollars on a car tire when my motorcycle was designed by countless engineers to operate with the recommended rubber. I will stick with their recommendation, feel better about it, and I'm sure when I'm going around a corner well over 100 miles an hour I will feel a lot better with my motorcycle Dunlop Tire. Now do whatever you like.

Brilliant, as always! I see the comment regularly that this is the best Motorcycle related content on YT but after nearly exhausting your library I am convinced you have the best "Do-It-Yourself" content on the Inter-Web! I watch everything from Auto-Centric to Xylophone Repair and Race/All Terrain/Off Road/4X4 to DIY of every topic and I do not see the consistent high quality and creative thoughtfulness of F9. Nobody, Nowhere, Knowhow. I will shut up now and start at the top. Thanks for the great Videos and for sharing your talents.

Americans in the comment section are like: „yeah, I have experience with car tires on bikes, it’s not optimal“ Europeans in the comment section are like: „YOU DID WHAT??????“

The most important thing this does for me is that it EXPANDS the size of my dating pool by such an increase in carry capacity. This is not just a motorcycle idea- it's social engineering.

Always knew this was a terrible idea, but this video did a perfect job of explaining why. Excellent work. Always wondered but never wanted to try this.

Again excellent writing and vid!! We all knew this instinctively (well except the issue of the tire wanting to flex back to perpendicularity). but dissection is the entertainment. Well done!!!

how come each and every video on this channel is a cinematic gem awesome production quality

Driving a car: Steer Wheel Riding a Motorcycle: *Look at these equations*

I like this guy, his voice and how he explains things. Very well presented and rarely rambles or doesn't waste time.

A video I've never searched for or wanted but found it really interesting, nice upload 👍👍😎😎

I've been putting motorcycle tires on my Truck for years now

Ryan: SCIENCE!! Also Ryan: F*#$!! 🤣🤘

Wow! Kudos, Ryan. Excellent journalism, potentially lifesaving. You rock.

I don’t own a bike, yet I’ve watched three of this guys vids and love em. Perfect mix of digestible knowledge, smart wording, and humor.

I've upgraded my suspension and eliminated the tires,I don't have to worry about flats, it feels like I'm riding on rails.

This is a fever dream of an episode. Like something out of black mirror.

Thank you for doing this and spelling out the details so clearly! This needed to be done! Handling is the most important (and well-designed) part of my Honda GL1800, and I wouldn't sacrifice it (by using wrong-shape tires) for anything. Smooth transition across the center point when going back and forth (and I ride in the mountains a lot) is critical to the DRIVER controlling the MOTORCYCLE and not the other way around.

the quality of these videos is just amazing. even with unlimited budget I doubt someone can do better.

1:44 a rare sight of Ryans burner phone for whenever he needs a gun to shoot motorcycle stuff with... for testing purpose ofc....

"We're motorcyclists, masters of measured risk"

Yet another GREAT F9 vid. Kudos. A large friend of mine runs car tires on his 1800 Goldwing. He says once you get used to the handling it's fine.

Exceptionally good evaluation of tires and how they work. Loved it.

Just... Just some of the best edited/filmed/shot/written and entertaining content on RU-vid (that I have come across). As both a motorcyclist and content consumer- Thank you for the time/effort you put into your work.

I love when the good ol' Canadian unit system comes out "a 4000lb car to travel 100,000km". Don't forget that travel distance is measured in time!

I hardly watch any 10 min. Video. Idk how but this guy keeps me hooked for longer than that all the time.

I'd never heard of it until the subject came up on a Bike forum a couple of days ago so I thought I'd try to find out more. Thanks for the very informative video. I slapstick to bike specific tyres and hang the cost. I am cost conscious but not to the point of jeopardizing my safety that much.

I think this is the first ever review of Darksiding where the review actually Darksides. My hat is off to FortNine on this one. Good job guys!

This is like if VSauce and Engineering Explained had a baby

Your videos are amazing, I cant believe I am just now finding your channel. Thank you.

Thanks, Ryan. Very well done, as usual! I have had a Semperit M&S tire on the back of a Burgman 650 scooter now for 3 years. Works fine, EXCEPT: longitudinal seams in the pavement are downright scary! Leaned over traction is not a problem, since the giant scooter does not lean over very far anyway; parts drag right away. The M&S tire actually gives some traction; the stock tire gets stuck on wet grass. Still not sure about tire pressure; anywhere from 25 to 40 seems to work just fine. Please note that I am a dirt rider, and might not be noticing some of the nuances of pavement handling. Thanks again!

That's an Awsome trick using your kick stand to break the tyre bead, I've never seen that before 👍👍👍

A few years back I bought a GoldWing that had a car tire on the back. Everything you said was valid. There was another issue that you didn't really cover. The hard rubber causes way less traction even in a straight line. The Wing would light up the tire every time I would accelerate, even with my wife on the back. It followed this up with locking up whenever the brake was applied. So, in addition to not cornering or going straight, it also couldn't accelerate or brake. But at least it would last the rest of my life. Just like a parachute that doesn't open.

I ride a HUGE Victory Vision, I weigh 260lb and I could not be happier going darkside. I have run flats and it handles just fine on the twisties. To each his own. (BTW put a car tire on my other bike as well/happy).

New your channel. I enjoy watching, very educational. I don't ride and I'm not well at physics's in anyway but you explain things very well

"spontaneous uninstallation" LOL.

I've got LEGO tires on my bike and everything is awesome!

Great video, worth a watch for the tyre changing method alone...wow!

Damn bro... you're throwing out facts like it's going out of style. I'm just trying to ride and not think about it. Great video.

You know they are doing something right when they don’t even tell you to comment, like, and subscribe but still get these due to their quality content

1:39 the use of cable ties are ingenious

Thanks for the clip. Explains a lot of things I was wondering.

Amazing content, amazing filming , amazing thoughts organizing, amazing editing

How can people give this video a thumbs down? F9 makes, in my humble opinion, the most entertaining, cool, educational motorcycle vids out there. Keep up the good work.

I have to disagree with the "higher mileage" point. Having been turning wrenches professionally on bikes for 15+ years, I have changed thousands of tires in my career. Many were utterly destroyed car tires. The tread wasnt hurt hardly at all. Its the sidewall that takes the hit. When you put big fat bikes on a 2 square inch contact patch while cornering, rubber flexes. Being that the sidewalls are drastically thinner, they flex first. This will generate excessive localized heat and wear and will eventually appear as if something was jammed into the side of the tire and rubbed a groove into it for a few hundred miles. Ive physically seen the sidewalls fail and cause the bike to go down, which totals the bike. And get this, these tires only had a few thousand miles on them. Maybe its different in flat states without a single turn for hundreds of miles, but out here in east TN where the road maps look like a plate of spaghetti, darkside is a big hell no!

And he selects an asymmetric tread design. Perfecto.

What a nice video I love the editing :D I love the new one too :)

These videos just keep being so well made, the explanation sections are just stellar, I wish my university lecturers could make their classes even half as engaging as this content

He's a real motorcycle guy, the flip phone proved it😂😂

Amazing editing and camera work 👌

Living and riding a Goldwing in Australia with large distances of flat straight roads, darkside makes sense. I agree with the tram track effect at times, but not always.

I have been using Dunlop 185/65/16 car tire since 2006 on my VTX 1800 it took a little getting used too but you run tire pressure depending on the bikes weight I ran 34 PSI and it stuck like glue even in rain and tripled my tire mileage to 40,000 km

I'm wondering what would happen, if you took a sidecar set up such as a Ural, and made it a darkside bike? The main problem with sidecars are that stability is a constant battle. But with your tires doing some of that work for you, would it make things easier?

great video and content, as usual, thank you FortNine!

Thanks for the video! I have a similar bike/tire combination. Question: Do you really need to fit it tubeless ??

Pneumatic tires, such as those on a motorcycle, Do NOT behave as classical dry friction theory would suggest. Rubber generates friction in three major ways: a) Adhesion, b) Mechanical keying, and c) Wear Furthermore pneumatic tires are sensitive to load, as they are loaded up the coefficient of friction decreases. Reference: The Racing & High performance tire, Paul Haney, 2003 Or wiki, if you guys don’t want to buy the book above. en.wikipedia.org/wiki/Tire_load_sensitivity

I put a Falken tire designed for the tuner market on my Honda VTX1800 and loved it. It was different from your choice in a couple areas. It has symmetrical tread, reinforced sidewalls, and rounded tread at the edges for better cornering. It did have better life and lower cost as you mention and better load capacity. What you didn’t mention was the better water handling capacity and the much better puncture resistance. I tested the tire with no air in it and it functioned for low speeds. Finally, when I had the second car tire put on the dealership called me and asked permission to cut the first car tire off the rim because it was so tightly fixed to the rim. The downside was low speed turning. You can definitely feel the bike as it transitions from the flat to side tread. I wouldn’t think of it on a sport bike but for a cruiser it was great. One last thing, My wife said the ride on the pillion was much smoother with the car tire. P.S. My original tire was tubeless and the rim geometry was not like what you show in the video.

I guess traction ist just fine when not in a curve... But I love to see this experiment. Great job.

Why am I just now discovering this guy? SUBSCRIBED

This is one of the best darkside videos I have seen. It’s not arguing for or against but simply putting the information out there. We darksiders will never say that the handling is better than a motorcycle tire and we would put them on our track bikes just that for the riding we do they are perfectly adequate. I went to the darkside on my concours after replacing 4 rear motorcycle tires in one year. It’s not a track day weapon, it’s a touring pig.

0:35 sooo that's what the side stand is for

I really enjoy your videos. Can you please make one or two videos on how to overcome fear of cornering after crashing on a corner? I had a bad spill on a motorbike I just bought (someone had thoughtfully dressed the tyres with silicone). I can now confidently negotiate left corners but feel panic creeping on when negotiating right corners and roundabouts. (I live in the UK so it is a problem.) Many thanks.

Excellent analysis and presentation. If you are not an engineer you'd make a good one lol. My buddy is a really big fellow and has been running a Michelin car tire on his goldwing for years. Swears by the ride and cost savings. Just wondering why you bothered sealing the rim and removing tube?

Its funny, i was just researching and watching videos about darksiding, and i noticed most of the users are cruiser riders. Really heavy bikes, without big lean angles. No suprise and your post confirms a lot for me

1:46 that was actually his trap phone

Thanks for all the info been watching for 3 years

I have a 85 Gold Wing 1200GL & Dark sided it with a Nexen 165/80/15 Cornering is no problem and now I have better braking, grip, water displacement and far better with a passenger + trailer. It also has an actual load rating...I'm staying on The Dark Side !.

I don’t how I haven’t seen this baby-faced scienctician before, but this single video garners an instant sub from me. You’re use of vernacular, and willingness to challenge ‘the norm’ are excellent. I look forward to perusing more of your videos!

7:37 Civic bois have left the chat

Your amount of knowledge is astonishing

Thanks for explaining this so competently I was considering this but after watching your video I think not😁👍✌🏍💨

Having been an auto mechanic back when the 16.5" truck tire was a thing, the darksiders lost me at "incompatible bead".. but as you said so well, let it go!

The Boss Hoss came with a car tire. Factory mounted. If I remember correctly that is. The handling as legend has it confirms your experiment on car tires on motorcycles. Well done sir, and very well explained what to expect and why.

That answers all my questions. Thanks !

I owned a Boss Hoss for a short time which used a wide car tire (on a car rim) at the rear. I didn't keep it long enough to get comfortable with the contact patch constantly moving left and right 10 inches when riding reasonably straight.

seriously great content! The soundscape in the first few minutes was phenomenal!

Darksiders chiming in. When the 1800 Wings came out, tire life of less than 10k was common, even 7k wasn't unheard of. Early on there were issues with tires delaminating due to underinflation and overloading. I was going through 2 rears and 1 front every year. I spent several days investigating everything I could find about darksiding. After all that and personal experience, this is what I concluded. The following link is my video with a camera under the bike. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-qoNDo7o1d6Q.html Not every tire works. Some designs work better than others. In my opinion, run flat tires are a must. The sidewall wraps around the rim and locks it in so we'll, that installation and removal is a bear. The rim profile mismatch is a fact, but the runflat sidewall locks onto the rim so hard, that I have to plan as much as 2 hours to change the tire when it's already off the bike. Handling is greatly effected by tire pressure. To high, and the tire doesn't flex enough. I run 25 psi cold and 30 two up, 34 fully loaded pulling a camper. Handling is different, but it's no problem to throw the bike around in the curves. The front tire effects the initial counter steering into a lean. When initiating a turn, I feel the front take the lead setting up for the banking turn. Once banked over, the bike will maintain it's lean angle. Even using cruise control in a curve, I can remove my hands from the bars and it maintains the bank. Off road traction is fantastic. I love riding dirt roads and trails. My current tire is a snow tire. I managed to drop my rear tire into a hole at a campground that the belly pan was on the ground while I had a trailer attached. The back tire climbed right out of the hole. I tested the run flat capability by removing the valve stem core and riding with zero air pressure. Normal riding was unaffected, while banking over just made the bike feel heavy. I was rear ended while having the car tire on. Progressive didn't care and even payed for a replacement car tire. Is darksiding for everybody, no. When properly installed and balanced ( I balance to + or - 1 gram ), using a tire pressure monitor ( you could get a flat and not know it ) and common sense, Darksiding works great. It's not something to just jump into. I respect the people who make RU-vid videos explaining the science of why it's not advisable. I understand the science, but I know how it works for me. As long as I'm riding my GL1800, it will never see a motorcycle tire on the back. Anytime we make modifications to our motorcycles, we have to accept that it's our responsibility for anything that might happen. I choose to run a car tire, and it's on me if anything ever went wrong.

Great info on the video! One thing I would recommend when inflating a tire on a rim it was not designed for is to put it in a cage or wrap a chain or ratchet strap through the rim and around the tire to contain it should the worst happen. If the tire blows off the rim when seating the bead, it could seriously kill you!😝

Well that friction force equation had me scratching my head. Thinking intuitively, it does make sense that if you have something really heavy, like a couch, on 4 little 1x1" legs with rubber feet, it's still hard to slide it sideways, just as it would be if each leg had 4x4" rubber feet. The fact that the force is only distributed on 1x1" patches doesn't obviously make it easier to slide.