Going to the Dark Side

[Cavy]

I tried to just start this in NEPRT, but you can't start threads there. I'm sure a helpful admin will move it for me shortly, at their discretion, of course.
I read about mounting car tires on bikes years ago. Mostly cruisers and HDs. I even rode an old Pan Head with one way back in the day. More recently I caught some discussion on one of the lists about it and read some more. Recently I decided to give this a try. At least to discover if it would work on the FJR at all.

I bought a used Cooper Zeon ZXS summer performance tire for cheap to test fit and today with DougC's help we mounted the tire and installed it on the bike. Below is a short report and some pics.

Apologies if you get this multiple times. It's going out to different lists.

So, things went fairly well. First off, it's a ***** to mount a stiff performance tire to a moto rim, even with the NoMar tire changer and three people, but it can be done. It takes all the tools you have though.

More tools stuffed in the tire

NoMar in use

And a 205/50-17 does fit on the FJR's 5.5" wheel, and fits on the bike, JUST. I think it just barely rubbed off the tops of some of the lettering on the sidewall with the brake caliper arm. There was about 1/8" clearance to the side stand legs as well. FYI, it rubbed a little when flat. :-( But not so much you couldn't push the bike around.

the bike

Ready to go test ride:

What did I learn? The car tire is wider than the rim, so mounting it requires more effort to get the first bead in the 'valley' of the wheel while you work the second bead on. And since the tire sticks out farther from the wheel, that means it doesn't like to sit flush on the NoMar pads. It's dished pretty good once you have both beads on the wheel. No need to seat the bead with high pressure, they are THERE. Possibly due to the rim design, the tire sticks out at the rim edge more than on a car. Not a problem, just an observation. Think rim protector beads X2.

For dismounting, it's very challenging to get the wheel lip onto the NoMar pad clips and locked in. I had to stand on the wheel spokes to exert enough down force to allow a second person to push the wheel into the pad clips and locked down.

I also learned to check used tires better for damage. :-/ The Cooper tire I bought for testing turned out to have two vertical slits in the side wall. Same side and they didn't leak with the tire inflated and just sitting there. They only leaked when the tire side wall flexed. I got a slow speed test ride in, but couldn't do an 'at speed' test due to the severe leakage.

The Cooper Zeon ZXS has very stiff side walls. It's a summer rated performance tire, so that was expected. Not much flex at 30 psi and one side would lift off the pavement when doing turns. I suspect a softer sidewall all season tire will not be as bad in this regard, but didn't feel it was a deal breaker on it's own, and didn't get the chance to play with different pressures due to the leaks. We could have patched it, but having learned 85% of what I wanted to learn, I didn't feel it was worth the effort to dismount the tire, patch it in two places, (making a total of three inside patches), and re-mount it.

What I noticed in feel is that during slow speed turns you can do everything you always could and it feels fine, traction wise, it's just that you get feedback in the bars when turning. A very noticeable pressure against you. You push left, it wants to keep going left to a tighter turn. You have to hold the bar position you want noticeably. This is parking lot drill speeds though. On the one short ride at faster speeds, (35 mph), I noted that the bar pressure seemed less and wasn't really that big a deal. Again, not a great test, just tooling down the neighborhood and making some swerves and a few turns.

I'm going to go ahead and order a new all season tire and give the Dark Side a try. I now know it will fit on the FJR and while handling is different, it's not so different or bad that I feel unsafe. There is just an adjustment period. I don't think it's a big deal to adjust to the car tire at this point.

I'll post more when I have the all season tire on and have some miles on it.

Did you chew on lead paint when you were little?

 

[user 213]

Losing sleep to change a tire at a checkpoint during the IBR is lame if you don't need to do it. And no one should DNF for a tire issue, that would be down right sad.

I can't let this one go by. With a spare rear wheel and someone helping you out, getting a fresh tire shouldn't take more than about 15 minutes. Half hour max, and that's if one of the parts rolls away.

We're looking at this from different sides of the fence. You're willing to sacrifice performance (1) to save a buck, I'm willing to pay for performance with money and time. Just different viewpoints.

(1) This is where the darksiders say that there's absolutely no performance loss with a car tire. I insist there must be some. When people start using them on the racetrack, I'll believe it.

We're not as different as you think Jerry. I agree with everything you just said, except the last (1) part. If you read the thread, you'll see that I've always been very clear about the extra turn in effort and loss of that effortless turn in feel for making transitions that a fresh moto tire has. I've tried to be very clear that while you can ride darkside hard, it's more effort and if you live for the performance/handling and ride hard in the twisties on a regular basis, the darkside is not for you.

In Iggy and SkooterG's cases, they both have extra wheels. I forgot about that when I suggested that they both should be looking at the Darkside. Personally, I still think it would benefit an IBR rider, even if only from the durability standpoint, (as in resistance to flats), and the improved handling in dirt/gravel/mud and on really bad non paved roads. For a rider that doesn't have an extra wheel waiting, the cost in time to pull the wheel and take it to a shop in person, wait for, or drop it off, then return, will be potentially significant. That might not be too many guys from what I've heard. Sounds like far more riders this year are prepped with extra wheels than in '07, or '05 when more assistance was allowed. Possibly due to the rule change.

@RogDeb - As Doug5551 shows in his pic, you use all of the tread. Thanks for the comments and I look forward to reading your impressions. I know you and Deb can RIDE, and I don't think the CT will slow you down a bit. Watch it on the first ride, there is a tendency to run wide in the turns until you get used to it.

@Cavy - Read posts #9, #22, #33, #103, #172(finally mounted a decent tire to ride on), #186, #188, #194, #199(first ride on the new tire), #201, #220, #234(first, wet, day ride), #333(multi-day trip report w/hooning in the twisties included), #337, #401(tire type/spec questions), #405(darksider #2 posts), #415 (13k miles on CT), #428, #434, #445(what to say to a shop for mounting/buying a tire), #481(front tire log info), #483(two up & weight talk), #488(darksider #3 posts).

Readers Digest Condensed version - #9, #22/33 on pg. 2, then skip to #172 on pg. 9 at bottom, #234 on pg. 12, #333 on pg. 17, #401 & 405 on pg. 21, #415, #488 on pg. 25.

 

[Fred W]

Did you chew on lead paint when you were little?

Anyone who quotes an entire, photo jammed post to make a one-line, smartassed comment deserves a good dog-piling, whether it's Friday or not.

:thumbsdownsmileyanim:

Hint: learn to trim your quotes please.

The only redeeming feature of your post is your avatar. :dribble:

I think she left the wine cellar door open...

 

[Calimus]

Yea, there definitly will be some cost to quick handling performance, especially when the CT is new. My father VTX was also in the catagory of very asy turn for such a bulky machine. Once the CT was on there, the first few corners gave me a tad of pucker factor. As was mentioned, untill you are used to putting in the extra input for the corners, the bike will want to run wide.

However, after being on for a year, the CT now handles somewhat like a MT. It still requires some different/extra input, but not nearly as much. He's put over 20K on the CT and I'd be willing to bet that he'll get close to another 20k from it.

The big point I see is this. If you ride like Jeff Ash, the CT isn't for you. If you find yourself constantly in the twisties pushing your skill and the machines limits, the CT isn't for you. If you are like me and wish to be a Jeff Ash or twisty monster, but find yourself slabbing back and forth to work far-far more then hitting anything with a real curve. Then the CT just might be your ticket. If all you are doing is wearing out the center of your $150 rear tire 2-3 times a year and the sides have more meat left then a fullsized heffer, then the CT might just be what you need.

For now, I can see dropping $125 for a CT that will get me through the next two years of slab with an occasional mild run through the twisties at a cost savings of around $700 for that time frame. When I get back to a point in my life where I can hit the mountains like a madman, the MT's will be going right back on.

This is my perspective on this, so that doesn't make it right, just how it makes sence to me.

 

[Catfish]

It looks like I have a partial sponsor.

A friend of mine who rides a Venture and owns a tire shop told me he'd give me 2 Aurora 205/50-17 for his cost ($60-$70) as long as I report my observations back to him.

I'm going put one on my '07 and my buddy that I sold my '04 to wants to try one also.

I'm gonna have to put my Ural away and start commuting on my FJR again.

I'm sure to take pictures and measurements and post them here.

After some quick Googling this is what I found.

https://tinyurl.com/ng69xc

 

[user 213]

More data is always good. I seem to recall the XL rated tires being slightly wider, but likely not an issue if you're going with the 3/16" bar.

 

[mdisher]

I'm gonna have to put my Ural away and start commuting on my FJR again.

This is the part I don't understand...

You have an FJR, yet you'd choose to commute on the Ural... :blink:

 

[dbx]

I have about 1500 miles on the CT since I put it on May 30. It works just fine. I have ridden about 300 miles of twisties over the last several days along Highways 330, 18, and 38 in Southern California. The CT is stable in turns and just takes a little more steering effort in Sweepers.

It doesn't sound like the additional steering effort is anything to be concerned about, and that you quickly adapt to it, right?

I started off a bit skeptical of this whole thing, but wow, after 26 pages and hundreds of posts, I'm giving it two thumbs up. This is looking very interesting!

 

[coastalcop]

tire came in today looks good, uniform in size no flat spots and will probably mount it tomorrow, unless it demands dinner and a movie first :blink:

would show a pic but no dice on the upload.

 

[Cavy]

Hint: learn to trim your quotes please.

The only redeeming feature of your post is your avatar. :dribble:

I think she left the wine cellar door open...

Sorry my computer skills are not up to par.

Anyone that would put a tire with a profile like that on a motorcycle and ride it on the street should have his drivers licence revoked.

He is not only endangering himself, but he might be next to me when he crashes.

There is a reason they make tires for motorcycles.

 

[palerider]

Anyone that would put a tire with a profile like that on a motorcycle and ride it on the street should have his drivers licence revoked.He is not only endangering himself, but he might be next to me when he crashes.

There is a reason they make tires for motorcycles.

They make motorcycles tires with a particular profile because of a perceived market for certain handling characteristics. If/when the tire manufacturers perceive an alternative market--say motorcycle tires that more resemble car tires--they'll make those. But just because it's called a car tire and not a motorcycle tire doesn't mean it's unsafe to use on a motorcycle as long as the rider rides within the tire's limitations. But that's true of motorcycle tires as well.

 

[Bobcattoo]

Even if the contact patch is larger assuming the total weight of the bike is unchanged, then the weight per square inch of contact area will be less with the CT. The total amount of force has to stay the same.

I think if you've watch a video of a CT in action on a GoldWing(YouTube) you'll come to the conclusion that the CT is exerting MORE lbs/sq.inch, in a curve. The tire is running on the very narrow edge in a lean.

Goldwing Darksider

 

[BugR]

First long term report from the road to CFR.

Very pleased with the tire, It is working well in all conditions even some muddy off road stuff (we got caught in a storm camping.)

The only down comment is that it can be very sensitive to ruts and edge traps on the straights, the curves are not a problem all.

It should be interesting to see the reaction at CFR

Chris

 

[user 213]

First long term report from the road to CFR.Very pleased with the tire, It is working well in all conditions even some muddy off road stuff (we got caught in a storm camping.)

The only down comment is that it can be very sensitive to ruts and edge traps on the straights, the curves are not a problem all.

I found that a little less tire pressure made an improvement in how the edge traps/ruts felt. Less catchy feeling, more of an crossing each edge of the tire feel.

@Cavy - Your opinion is noted. Also noted is that it appears to be based on no personal experience with a CT. And that it's pretty much been said before. You'll pardon me if after 15,000 miles on the CT and no crashes or other issues, I don't really give your opinion much weight over my personal, direct experience.

 

[Ignacio]

@Cavy - Your opinion is noted. Also noted is that it appears to be based on no personal experience with a CT. And that it's pretty much been said before. You'll pardon me if after 15,000 miles on the CT and no crashes or other issues, I don't really give your opinion much weight over my personal, direct experience.

Well played Mr. V. ......snerk.

 

[kansas transit]

OK, OCfjr, I have read this thread from the very begining. I thank you for not only thinking outside the box but also for puting in the time (guinea pig?) to inform us of your findings, but I do have a couple of quetions.

Since we seem to have a lot of cross wind here in Kansas and I notice that somtimes in a cross wind the bike wants to "hunt" for a line so to speak, does the CT seem more stable, less stable, really makes no differance?

Since it seems, that most people that have a problem with this, have not so much an issue with either the compound or makeup of the tire, but more so with the PROFILE of the tire. So I have a suggestion, in fact you may also find that it could help your turn in somewhat.

Take your CT to a tire retreader, have them "lightly" shave or radius the first and maybe part of the second rib to give you the more rounded profile that everyone is looking for.

The operation is cheap, we used to run a roundy rounder car class that dictated DOT tires. But new DOT tires have to much rubber or TIRE SQUIRM so we used to have about 1/2 of the tread shaved of.

Your probably talking around 15.00 to shave a tire, and with the compound of the CT I would think that radiusing the outer rib would not detract from your overall milage goals.

Let me know what you think, It sounds to me like you are very happy with what you have, but you had mentioned in a couple of your posts looking for a CT with maybe a more rounded profile. With that not available I jut thought that this might be somthing worthwhile, at the same time quieting some of the nonbelievers.

JMHO Stan

 

[coastalcop]

Going to mount the tire after work today, cant wait!

 

[user 213]

OK, OCfjr, I have read this thread from the very begining. I thank you for not only thinking outside the box but also for puting in the time (guinea pig?) to inform us of your findings, but I do have a couple of quetions.

Questions are good!

Since we seem to have a lot of cross wind here in Kansas and I notice that somtimes in a cross wind the bike wants to "hunt" for a line so to speak, does the CT seem more stable, less stable, really makes no differance?

Hard to compare since I haven't ridden in the same conditions, on the CT, then immediately on a moto tire. The CT doesn't seem to have any impact on wind stability. If there is enough wind to push me around, that seems to be more of a function of bike cross section & weight more than anything else. i.e. lightly loaded with a top box being worse than heavily loaded with no top box or other external loads. I also don't run a large windscreen, so generally don't have much of an issue with cross winds. Enough and I'm certainly in a lean & feeling it's effects, but don't recall any more, or less of a problem holding my line with the CT.

Since it seems, that most people that have a problem with this, have not so much an issue with either the compound or makeup of the tire, but more so with the PROFILE of the tire. So I have a suggestion, in fact you may also find that it could help your turn in somewhat.
Take your CT to a tire retreader, have them "lightly" shave or radius the first and maybe part of the second rib to give you the more rounded profile that everyone is looking for.

The operation is cheap, we used to run a roundy rounder car class that dictated DOT tires. But new DOT tires have to much rubber or TIRE SQUIRM so we used to have about 1/2 of the tread shaved of.

Your probably talking around 15.00 to shave a tire, and with the compound of the CT I would think that radiusing the outer rib would not detract from your overall milage goals.

Let me know what you think, It sounds to me like you are very happy with what you have, but you had mentioned in a couple of your posts looking for a CT with maybe a more rounded profile. With that not available I jut thought that this might be somthing worthwhile, at the same time quieting some of the nonbelievers.

An interesting idea. I had forgotten about racers shaving tires. Typically taking them down to 4/32" to minimize squirm and improve cornering stability. Was a big deal in Solo II long ago when I did that.

Because of the way the CT shifts on the sidewalls, I'm not sure that shaving all the way into the second rib would be as beneficial since the CT isn't rolling over like a moto tire does, but shaving or radiusing the first rib might have interesting and positive results w/o suffering premature wear. Depending on what tire I go with next, I very well may try your idea and see how it performs. Thanks for your suggestion. :good:

 

[RadioHowie]

Depending on what tire I go with next, I very well may try your idea and see how it performs. Thanks for your suggestion. :good:

Whaaaat!!! We gots to wait 3 years before you need a new rear, and THEN you'll "try" a shave?

:impatient smiley:

 

[kansas transit]

OK, OCfjr, I have read this thread from the very begining. I thank you for not only thinking outside the box but also for puting in the time (guinea pig?) to inform us of your findings, but I do have a couple of quetions.

Questions are good!

Since we seem to have a lot of cross wind here in Kansas and I notice that somtimes in a cross wind the bike wants to "hunt" for a line so to speak, does the CT seem more stable, less stable, really makes no differance?

Hard to compare since I haven't ridden in the same conditions, on the CT, then immediately on a moto tire. The CT doesn't seem to have any impact on wind stability. If there is enough wind to push me around, that seems to be more of a function of bike cross section & weight more than anything else. i.e. lightly loaded with a top box being worse than heavily loaded with no top box or other external loads. I also don't run a large windscreen, so generally don't have much of an issue with cross winds. Enough and I'm certainly in a lean & feeling it's effects, but don't recall any more, or less of a problem holding my line with the CT.

Since it seems, that most people that have a problem with this, have not so much an issue with either the compound or makeup of the tire, but more so with the PROFILE of the tire. So I have a suggestion, in fact you may also find that it could help your turn in somewhat.
Take your CT to a tire retreader, have them "lightly" shave or radius the first and maybe part of the second rib to give you the more rounded profile that everyone is looking for.

The operation is cheap, we used to run a roundy rounder car class that dictated DOT tires. But new DOT tires have to much rubber or TIRE SQUIRM so we used to have about 1/2 of the tread shaved of.

Your probably talking around 15.00 to shave a tire, and with the compound of the CT I would think that radiusing the outer rib would not detract from your overall milage goals.

Let me know what you think, It sounds to me like you are very happy with what you have, but you had mentioned in a couple of your posts looking for a CT with maybe a more rounded profile. With that not available I jut thought that this might be somthing worthwhile, at the same time quieting some of the nonbelievers.

An interesting idea. I had forgotten about racers shaving tires. Typically taking them down to 4/32" to minimize squirm and improve cornering stability. Was a big deal in Solo II long ago when I did that.

Because of the way the CT shifts on the sidewalls, I'm not sure that shaving all the way into the second rib would be as beneficial since the CT isn't rolling over like a moto tire does, but shaving or radiusing the first rib might have interesting and positive results w/o suffering premature wear. Depending on what tire I go with next, I very well may try your idea and see how it performs. Thanks for your suggestion. :good:

Great, NOW what about that pesky front tire????

By the way, ran into a guy on a ZX 10 this morning,,,,, you guessed it CT. LOL