Darkside.....Yes or No?

First topic message reminder :

Would you fit a "Darkside" tire on Your Silverwing?? .........What size, and what name brand, why, or why not?? Thanks Jeff.

There are videos on this site and more on the right column... enough to learn all about flexing and traction questions you might have. They report ,,,, you decide....

https://www.youtube.com/watch?v=gZKhoFbL7Fo

Hi OP..........now thats an eye opener!.....Gotta go back and watch it again, as the first time thru, I was just waiting for the camcorder to meet its maker. Thanks much OP, and hope you're enjoying the Arkansas hills and dales. I'm going to Google Earth Rison. Jeff.

OP.....the video of that Dunlop on that two wheeler is worth watching. Thanks much. Rison looks like the perfect place to raise a family. I cant believe how good Google Earth is. OP......are those hog confinements just downwind of town??????? We have many around Quincy, and at certain times it gets a little.......uh..........Websters dictionary........uh.......Odiferous!.........Is that a word for " Man that stinks"? Jeff.

I agree cars tire last a long time on bikes....


But who is considering difference in rim design between car and mc wheels? Sudden air loss ? I know hasn't happened or at least no-one who had it speaks up. Dead?

Last and I will be quiet.----car tires are different compound=hard. What happens in wet/cold? East Germany used to have some wonderful hard bike compound tires-pneu-mat(sp?) they wore like iron----not much fun on block pave or wet or cold. Lasted quite awhile on MZ two stroke sidecar outfits. I had some what turned out to be hard compound AVON tires on my Concours----great at 85 degrees two up, tires were hot. At 35-40, wet cold really bad.Hard too keep bike going upright, straight line. Not fun.

I have yet to hear from any body who has run up big miles on car tires---like 100-150,000 miles and their experiences. They are the ones who might have something to relay.


John Grinsel

john grinsel wrote:

I have yet to hear from any body who has run up big miles on car tires---like 100-150,000 miles and their experiences. They are the ones who might have something to relay.

One of the earliest (that I've found on the Internet) users of a Darkside rear tire has a great site: http://lifeisaroad.com/stories/2004/10/27/theDarkSide.html

He has well over 100K miles running on darkside tires. There is an entire section of the Goldwing riders forum devoted to people who have been, and are using darkside tires. I'm certain they have amassed far in excess of 100K miles, maybe millions of miles, on their darkside tires.

Having said that, if you don't want to use one, that's cool. I don't have one on my machine either. I don't ride enough distance to make it worth the trouble of finding someone to mount it, and I'm happy w/the ride I have now. If I ever need to ride 10K miles on one trip, I would consider installing one for sure...

Hi John.....Hi Sween. No matter what.....lets keep talking and sharing what we know, and what we think. Theres nothing better than putting aside what we believe and accept.........and digging in with a little critical thinking. Cant wait to find out what's around the corner!..........Jeff.

john grinsel wrote:

But who is considering difference in rim design between car and mc wheels?

The tire rim design is round and designed to hold a round tire.

The outside width of the rear rim is 5.093" well within the Sumitomo specification of Rim Width Range: 4-5.5".

The Sumitomo car tire consistentlyhas less air loss then the OEM Bridgestone ... so the tire/rim seal is doing better than the original OEM Bridgestones.

john grinsel wrote:

Sudden air loss ? I know hasn't happened or at least no-one who had it speaks up. Dead?

My first Darskide tire was replaced (3,000+ miles) due to a 3/4" open gash from unknown road debris that went through the ENTIRE tire/tread and cutting radial cord(s) while in the middle of a 90 degree. I traveled 3 miles at 65-70 MPH with no problems or signs or trouble ... there was not a single sign of trouble. The last mile was morning traffic which was 0-20 MPH.

john grinsel wrote:

Last and I will be quiet.----car tires are different compound=hard.

You are espousing incorrect facts.

There is a measurement device device called a Durometer which measures the hardness of tires. The car tire was found to be equal to high performance motorcycle tires and softer than normal motorcycle tires.

john grinsel wrote:

What happens in wet/cold?

The Sumitomo has handled flooded roads better the the front tire and original OEM Bridgeston rear tires.

No problems or difference in cold weather.

Two points:


#1 if car tires are so great why don't road racers use them? or why aren't they OEM ?

#2 There is difference in rim bead design between car and bike. I believe SAE paper was done on it.


My true feeling is car tires users on bikes may not be able to feel differences in handling/behavior of bike.

Tires very sensitive issue----I suffered 80mph dry cornering slide---some going too fast, most tire. changed from OEM Conti to Japanese Dunlop K-70? on rear of my then new BMW R60/6----Hard compound tire=breakaway slide----could have killed me. Bike or I did not go down but a thrill to last lifetime. Is car tire on scooter maybe going to do same thing. Anybody taken rear car tire scooter to track day?


John Grinsel

honda_silver wrote:

The tire rim design is round and designed to hold a round tire.

The outside width of the rear rim is 5.093" well within the Sumitomo specification of Rim Width Range: 4-5.5".

As I understood John's assertion about the wheel design - he was referring to the bead seat of the rim relative to the bead of the tire. Is there a difference between the MC tire and the car tire bead? Seems as though there is, I don't know, but will check when I get home.

honda_silver wrote:

The Sumitomo car tire consistentlyhas less air loss then the OEM Bridgestone ... so the tire/rim seal is doing better than the original OEM Bridgestones.

Given that you have experienced less air loss - I don't know if that proves that the tire/wheel seal (bead seal) is better. The tires are constructed differently - from more plies to different construction and compounds. These variables may also be a factor or could be contributing factors resulting in you experiencing less air loss.

honda_silver wrote:

The Sumitomo has handled flooded roads better the the front tire and original OEM Bridgeston rear tires.

No problems or difference in cold weather.

I'd dump that front tire and replace it with a skinny car tire if it is so unsafe... Just kidding Bill, this is a surprisingly emotionally charged issue.

SUV Update. Silverwing Utility Vehicle that is. Riding to work this morning.......there it was. I am the caretaker of a campus, and on lot #2 an 18 foot branch was taunting me. Well, could get the tractor and trailer, or tractor and chain..........whats that Mr Sumi?.....theres a tiedown under the seat you say?.......Thats crazy. " But schools in and some youngster could trip on that toothpick and scuff their $300 sneakers"." Do you want to talk to Suzy's mom and her lawyer and probably her therapist? O.K. Muy Macho Sumi.....we will save the children from this evil limb from Hell. Towed 'er across two parking lots, and received the Key to the City. I wonder if Sumitomo makes a mud and snow tire?
Jeff.

No, but Pirreli does. I contemplated getting one when I added the Danson kit, but used a same size (165/65 radial) Bridgestone.

jdeereanton wrote:

Given that you have experienced less air loss - I don't know if that proves that the tire/wheel seal (bead seal) is better. The tires are constructed differently - from more plies to different construction and compounds. These variables may also be a factor or could be contributing factors resulting in you experiencing less air loss.

That was exactly the same arguments years ago when the new fangle "radial tire" versus the old bias-ply tires. Today most tires are radial.

jdeereanton wrote:

honda_silver wrote:

The Sumitomo has handled flooded roads better the the front tire and original OEM Bridgeston rear tires.

No problems or difference in cold weather.

I'd dump that front tire and replace it with a skinny car tire if it is so unsafe...

If I find a front darkside tire that I like .... I may try it.

honda_silver wrote:

jdeereanton wrote:

Given that you have experienced less air loss - I don't know if that proves that the tire/wheel seal (bead seal) is better. The tires are constructed differently - from more plies to different construction and compounds. These variables may also be a factor or could be contributing factors resulting in you experiencing less air loss.

That was exactly the same arguments years ago when the new fangle "radial tire" versus the old bias-ply tires. Today most tires are radial.

Well.... I wasn't really expecting an answer, so imagine how much I was not expecting a non-answer.

Trees have leaves but not the conifers????

I'd guess that when you changed the tire you may also have changed the valve stem. Would that have an impact on the lack of air pressure loss?

We switched to a different brand of rear tire (MC) and it holds better pressure than the previous brand. Is it the tire? The valve stem? The install? A blanket statement that dismisses other factors or simply does not take them into account is not a valid statement.

As such, I don't think it is possible to simply say that the car tire bead seats better and for proof you offer up the anecdotal evidence that you don't have to fill it as often. I'm just saying. It is possible, I'd just rather have all the information or at least some quantification.

john grinsel wrote:

#1 if car tires are so great why don't road racers use them? or why aren't they OEM ?

Rear darkside tire are OEM on some models of Boss Hoss and some custom motorcycles.

john grinsel wrote:

My true feeling is car tires users on bikes may not be able to feel differences in handling/behavior of bike.

My answers are based on experience not "feeling".

john grinsel wrote:

Tires very sensitive issue----I suffered 80mph dry cornering slide---some going too fast, most tire. changed from OEM Conti to Japanese Dunlop K-70? on rear of my then new BMW R60/6----Hard compound tire=breakaway slide----could have killed me.

Use a softer compound tire .. a darkside tire

john grinsel wrote:

Bike or I did not go down but a thrill to last lifetime. Is car tire on scooter maybe going to do same thing.

The darkside tire has save me from numerous thrills that would have occurred with normal motorcycle tires.

1) One day the maintenance staff packed sand onto decorative pavement blocks ... the sand matched the color of the blocks and the excess sand was not removed. When I came out of the parking garage in the middle of my 90 degree turn to exit ... the front wheel started sliding out and the rear darkside tire following the exact same did not slide out.

2) I found the Darkside tire to be better on the worst tar strips material. There were some HORRIBLE and dangerous tar snakes from the white road perimeter paint while zig-zagging across the construction zones. The front tire would slide and the rear darkside tire was very stable.

3) Texas does not always post signs when they groove their pavement ... even at dangerous spots like the middle of a turns at posted curve speed limits.. The original OEM Bridgestone would track in the "v-groove". The darkside tire greatly reduced the "tracking".

So the darkside tire has helped prevent situations.

john grinsel wrote:

Anybody taken rear car tire scooter to track day?

I do not care one ioata about track time. So no ... I am not going to. Some insurance companies are removing "coverage" while motorcycles are at a track.

Jeff Rosenkranz wrote:

Would you fit a "Darkside" tire on Your Silverwing?? .........What size, and what name brand, why, or why not?? Thanks Jeff.

Sorry - one more thing - after much research, the Sumitomo HTR T4 is the most technologically advanced tire I found on the market today. It seems to be the choice of 50+ % of the riders I viewed. It was my choice, and except the the mounting, is a WONDERFUL choice for a quality "darkside" tire.

Car tire may have more contact patch in straight up straight forward situation----but bikes are designed to lean.....including accident avoidance maneuvers.


Does larger contact patch effect interconnected brake ratios----think it was designed with specific traction amounts in mind? Remember front is doing about 70%of the work in braking...maybe more as you add front yourself in linked system.Hard to mount-----didn't everybody mount their own tires? I heard in addition to getting bead to seat, some stretching required to get bead over rim.?

This talk of car tires will never end---I really don't think the people who are so pro car tire have #1 really ridden a lot in their life (most here seem to be old) and presently don't do lots of riding----if car tire can last 30,000 miles---you would need one at least every 18 months, if your are doing serious riding. Nor interested in Track Days or possible training to improve skills.

Any Iron Butt people use car tires? When I saw Ed Otto finish Iron Butt in UT on Helix, he had scooter tires.


John Grinsel

Gosh John.....I had a Sumitomo dealer mount mine. They were nice folks. Sure they had to stretch it over the rim. I wouldnt want to ride anything that wasn't clinched. I have ridden a lot.......I have owned 28 motorcycles and I sure hope to add more in the future. I have had track time. Participated in the Yamaha YSR series.....learned how to drag my knees and almost got to the magic elbow touchdown. Also had track time on my dirt bikes. But never had the chance to do any laps with most of my bikes. Really didn't want to ride my old BMW or my c70 Honda Passport in that environment. And OLD.....did you really say OLD.......why yes I am. BUT......I still walk, kayak, bicycle and canoe. And I'm still pretty good at roller skating and not to shabby on a skateboard. Did you really say Old??? Yes....but wise also. Jeff

Wait......I need to add to that. Wise.....but not to smart. For the love of Pete.....I have a Tire on the back of my Honda Silverwing that would fit on a Ford Escort......I have got to get more fiber in my diet. Nursey Cratchit......can I have more prunes......No, No,......not the tube.....AHHHH!!!!! Jeff. Are there any Silverwing owners interested in or have actually ridden at 8 or 9/10ths on a track......??????........with car parts on their SW's??? Yes Nursey Cratchit.....the Orange Metamucil will be just fine!!

john grinsel wrote:

-----didn't everybody mount their own tires?

I don't mount my own tires. That's why tire shops exist. The folks I work for provide a full engineering solution, but none of the owners are engineers. I don't need to know how or even do the task if my good friend the wallet can do it for me.

john grinsel wrote:

This talk of car tires will never end---

Sadly this is a true statement.

john grinsel wrote:

---I really don't think the people who are so pro car tire have #1 really ridden a lot in their life (most here seem to be old) and presently don't do lots of riding----

Not true John, Bill has many many miles (40,000?) on a car tire. "Riding a lot" is very subjective. If we are going to willy nilly proclaim that people are not allowed to have comments because of some arbitrary standard(s) set by a single individual - I'd like to know where I apply for that job.

john grinsel wrote:

----if car tire can last 30,000 miles---you would need one at least every 18 months, if your are doing serious riding.

You'll need a new car tire once every 3 months if you're a real rider!

Hey Jeff,

What a good life!!! Here comes Nursey Cratchit.....with the Orange Metamucil....A DOUBLE FOR EVERYONE!!!!!

John, I'm about to put on a Sumitomo and I'm 33 and a member of the Iron Butt Association. My reasoning for wanting to try this is because I don't want to have to get new tires every few months.

I took a very short spin on Cosmic Jumper's darkside Swing a few weeks ago and had completely forgotten that there was a car tire on the back, and didn't even feel any difference in the handling at all. And I was going on a really bad road.

Most of my long distance riding is on interstates, and just in case you're wondering, John, my idea of a long distance ride is that anything less of 500 miles in a day is a short day, 1000 miles is a long day, and 1500 miles is gonna mean I don't go to work the next day. I'm not putting this out there to brag or show off. I just don't think you realize how many different types of riders are on here, and that any assumptions made online rarely pan out. Another example: many of my fellow IBA members are in their 60s, and some are even in their 70s and 80s, and several of them ride 100k miles in ONE year. My good friend is currently riding a stock Yamaha Majesty in the Iron Butt 5000 right at this very minute. He'll be riding over 5000 miles in 5 days. And he's in his 60s.

Anyway, I'm going to try the Sumitomo simply because I ride over 20k miles in a year and I don't want to have to keep buying tires. Ideally, I would LOVE to have another wheel so I can switch to my Pirelli Diablos (very grippy tires but don't last much more than 8000 miles) for when I want to go canyon carving and then the Sumitomo for when I'm going on a long ride.

We're all individuals with our own personal choices. We all do what works for us depending on the riding we do. One of my Gold Wing friends uses a rear tire mounted backwards on the front. I have no idea what you even call that -- a Backside tire? Other folks are purists and insist on just stock alone. It's all good and fine.

I think trying to figure out whether or not to go Darkside is best figured out by just trying someone's bike while armed with the knowledge that this wonderful forum provides. If you tried it before and didn't like it, John, that's perfectly fine and I'm glad to hear it -- not everyone will like something or it'd probably be too good to be true (i.e., those who didn't like it just decided to keep quiet). The rest of us will have to figure it out for ourselves when we actually try it.

Good one DennisB. We can all stand a dose of good humor......on a "Regular" basis..........S'cuse me....is there a restroo..........OOPS.

john grinsel wrote:

#2 There is difference in rim bead design between car and bike. I believe SAE paper was done on it.

Is this available online for all to read? (I'm not trying to be argumentative, I'd serious be interested.)

john grinsel wrote:

Does larger contact patch effect interconnected brake ratios----think it was designed with specific traction amounts in mind? Remember front is doing about 70%of the work in braking...maybe more as you add front yourself in linked system.Hard to mount-----didn't everybody mount their own tires? I heard in addition to getting bead to seat, some stretching required to get bead over rim.?

Since more force is put on the front during braking, then wouldn't that mean that whatever you have in the back is less consequential then? And as others have mentioned, all tires have to stretch a little to get them all (yes, I've mounted tires before), even 'real' motorcylce tire.

john grinsel wrote:

This talk of car tires will never end---I really don't think the people who are so pro car tire have #1 really ridden a lot in their life (most here seem to be old) and presently don't do lots of riding----if car tire can last 30,000 miles---you would need one at least every 18 months, if your are doing serious riding.

No, it probably won't end. But to ride a lot, to do 'serious' riding on a car tire and generate more experimental data for people to draw their own conclusions from and maybe find a better tire for their particular application, well, that requires that someone try it first. You can't drive 100k miles (with or without a car tire) unless you drive 1 mile, then 2 miles, then 3...

Even if I never go over to the dark side, my hat's off to those who are experimenting :not worthy:

john grinsel wrote:

I really don't think the people who are so pro car tire have #1 really ridden a lot in their life (most here seem to be old) and presently don't do lots of riding----if car tire can last 30,000 miles---you would need one at least every 18 months, if your are doing serious riding. Nor interested in Track Days or possible training to improve skills.

Any Iron Butt people use car tires? When I saw Ed Otto finish Iron Butt in UT on Helix, he had scooter tires.


John Grinsel

You haven't been reading the darkside forums much, have you? There are a TON of long distance riders using darkside tires, reading their experiences and discussions aroudn darksiding is what made me realize my initial feelings were likely incorrect.

As for arguing, that won't end ever, it's human nature.

John.....Stick with us here.......You have a lot of two wheeling experience, and we honor your opinions. Jeff.

honda_silver wrote:

Jeff Rosenkranz wrote:

Thanks for the heads up about the mold protection. Is this something sprayed on the tire?

I do not know if it sprayed or coated

Jeff Rosenkranz wrote:

Slippery?

I would not push ( or try to gauge ) the tire in corners till after it is completely scrubbed and be more careful when wet. Once the tire (not just the center ) is completely scrubbed ... there is no issue.

Jeff Rosenkranz wrote:

did you purchase your's at a tire shop, internet,....how much

Internet www.tirerack.com ( do not mention you are putting on a motorcycle) ... you are mounting a tandem axle for hauling gear .

Jeff Rosenkranz wrote:

Question, I recently set my rear shocks at the stiffest possible and I noticed a big improvement in the feel in the front end. If the Sumi tire is taller, how does this translate in front end feel.

Difference between OEM 150/70R13 and Sumitomo 165/70R13 in inches:
...
Overall
Diameter: 0.82

SWing Wheelbase 62.8 inches

If I did
my Trigonometry Oblique Triangle calculation correctly then it
is a 0.9999 degree difference ... which is very small (insignificant).

The same tire is cheaper (and the shipping too) at tires-easy.com

honda_silver wrote:

Jeff Rosenkranz wrote:

II've just clicked on Tirerack.com and noticed that there are different performance and season options with the Sumi tire. Which did you choose for your SW.?

http://www.tirerack.com/tires/TireSearchResults.jsp?width=165%2F&ratio=70&diameter=13&startIndex=0&search=true&pagelen=20&pagenum=1&pagemark=1&manufacturer=Sumitomo&x=15&y=11

HTR T4 165/70R13

Hammy wrote:

Sweet! u guys are definitely selling me on a darkside tire once my Diablo fades... I searched tire rack but only found one tire -- not sure what options were available to you , Jeff? I also noted that the tire is 165/70 whereas my Diablos are 150/70... is that more of an issue of availability or any reason the tire size is different?

Quite simply, there just isn't a 150/70-13 automotive tire out there. Because of the generous swingarm clearance on your Swing, and because someone WAY back "experimented" with the 165, we know now that it fits and works. Make sure to order the tire from tires-easy.com. Both the tire and the shipping are cheaper. Mine was on my doorstep in about 5 days.

Good on ya Slick. Thanks for the summary's, and the heads up about Tire-Easy.com. Now in all fairness........I need to experiment with four new motorcycle tires mounted to my Geo....... I have the feeling that I might win a "Drifting" competition. Who knows? After the Paramedics patch me up, I would like a private room tho.....just in case Nursey Cratchit feels a little frisky. Jeff.

Jeff Rosenkranz wrote:

Good on ya Slick. Thanks for the summary's, and the heads up about Tire-Easy.com. Now in all fairness........I need to experiment with four new motorcycle tires mounted to my Geo....... I have the feeling that I might win a "Drifting" competition. Who knows? After the Paramedics patch me up, I would like a private room tho.....just in case Nursey Cratchit feels a little frisky. Jeff.

A "dark sided car"? On all four wheels? Now THAT would be fun to try. Post some pics with Cratchit in the passenger seat after you get them put on

Hi Ed.......I shoulda been driving that Geo yesterday, as I wound up riding 35 miles in the rain. A 15 minute downpour with 50 mph gusts and I was dialing Nurse Cratchits home phone......the rest was just a steady rain tho. The Sumi felt great on these country two laner's. There was a section that had been tar and chipped, but had become nothing but tar. Looked like ice in the rain.......slowed and gradually felt comfortable with a steady 50mph all the way home. Once I got to town, I purposely tried to rear brake hard enough to the point of a slide. Felt predictable, excellent control. Tried to spin it at a couple intersections with out going overboard, with no luck. Needed some crosswalk paint strips to really try the Sumi, but by now I'm soaked, cold, and happy to be home. Sumi wet weather road test.............Thumbs Up!! Jeff.

Jeff Rosenkranz wrote:

...Needed some crosswalk paint strips to really try the Sumi...

And maybe a couple of man-hole covers, too I wonder, does putting crosswalk paint on a man-hole cover make it more or less slippery...

I would like to have one of those trike kits with Sumi's mounted to answer that question........Super Slippery I bet. Quincy has a storm sewer that empties into the Mississippi. This underground line drops down the bluff before hitting the river, and during a big rain, that man hole cover dances better than Pole Dancer Cratchit at DennisB's soon to be yearly barbecue at Huntington Lake. Hmmmmm....Pole Dancer Cratchit.....????.....hopefully ShaniaB will fill in if PDC gets called in at the hospital. Jeff.