Thinking about a wider rear tire

[CIP57_imp]

I found a couple manufacturers that have a 180/55-18 tire. Using an online comparison tool, I found that this size is almost the same diameter as the factory 140 tire. Finding a 5.5 inch rim and making it all fit is next. The spoke wheels may be an option. I've seen many times where a wider wheel hoop was laced onto an original hub so a wider tire could be run. I personally like the non spoke wheels that come on the CB.

The center stand may pose a problem like you mentioned. Once I get a tire I'll start working thru the details.

If you're going to change rims why not go with 17 inch front and back where there's more availability of sport tires. A 180 rear is going to require a 120 front otherwise you're going to be pushing out of corners. Clearance is real tight upfront I'm not sure if 120 will fit without some sort of modification

[Calamari_imp]

I found a couple manufacturers that have a 180/55-18 tire. Using an online comparison tool, I found that this size is almost the same diameter as the factory 140 tire. Finding a 5.5 inch rim and making it all fit is next. The spoke wheels may be an option. I've seen many times where a wider wheel hoop was laced onto an original hub so a wider tire could be run. I personally like the non spoke wheels that come on the CB.

The center stand may pose a problem like you mentioned. Once I get a tire I'll start working thru the details.

If you're going to change rims why not go with 17 inch front and back where there's more availability of sport tires. A 180 rear is going to require a 120 front otherwise you're going to be pushing out of corners. Clearance is real tight upfront I'm not sure if 120 will fit without some sort of modification

If you're going to change rims why not go with 17 inch front and back where there's more availability of sport tires. A 180 rear is going to require a 120 front otherwise you're going to be pushing out of corners. Clearance is real tight upfront I'm not sure if 120 will fit without some sort of modification
Yup, good info. Once I get a 180 in my hands I can figure all that out. I agree that the 17 inch, 120/180 combo is pretty standard and works well on a lot of sportbikes.

[offroadfx4_imp]

Don't get me wrong I DO love the look of a big fat rear tire....I was in love with the 2014 CB1000R for that reason among others, but it just didn't fit my body.

http://www.tflcar.com/wp-content/uploads...R-RWhl.jpg

One thing I thought I'd point out, I had a physics professor point out one time....if the reason for a big tire is added is for friction, that's a false assumption, because surface area doesn't actually exist in the physics formula for friction.

http://www.pstcc.edu/departments/natural...201310.htm

However, from what I remember, the reason wider tires are more successful at providing more friction than narrow tires is because wider tires can dissipate heat better. A little skinny tire on a funny car dragster tire would just melt immediately and lose all friction. Wider tires can absorb and dissipate that heat and remain intact.

If that is true and we aren't out there power sliding our CB's around curves, I'm not sure wider tires would actually help much.

I know there are a lot of educated people on here so if anyone can clarify, correct or enlightening me on this I'd be glad to correct my remembered conclusions on this subject I've carried around for years ;-)

[Pterodactyl_imp]

^^^^. Correct. But, that formula calculates the coefficient of friction between two surfaces. Not the total of the friction that exists between two surfaces that would need to be overcome by a force before break away occurs. That is traction.

Simply put, for any given tyre compound at any given temperature on any given surface, the greater the contact patch the greater the traction. Therefore tyre size and shape, all other things being equal, determine the traction.

The temperature of a tyre also helps determine the amount of traction provided. As the tyre gets warmer the compound becomes more compliant. This increase the contact patch. Thus tyre earners. This increased traction continues until the compound exceeds its design temperature, causing the tyre to leach oil or the tread separates, or both.
Cheers

[Pterodactyl_imp]

^^^^. Correct. But, that formula calculates the coefficient of friction between two surfaces. Not the total of the friction that exists between two surfaces that would need to be overcome by a force before break away occurs. That is traction.

Simply put, for any given tyre compound at any given temperature on any given surface, the greater the contact patch the greater the traction. Therefore tyre size and shape, all other things being equal, determine the traction.

The temperature of a tyre also helps determine the amount of traction provided. As the tyre gets warmer the compound becomes more compliant. This increase the contact patch. Thus tyre earners. This increased traction continues until the compound exceeds its design temperature, causing the tyre to leach oil or the tread separates, or both.
Cheers

[offroadfx4_imp]

You have my curiosity going....I never considered friction as being different from traction.

I did find some interesting references...I know the following guy in not a scientist but he makes some good points and it's specific to motorcycles, tire size and leaning. I'm not sure I agree on everything he says, but it's an interesting read.

http://www.stevemunden.com/friction.html

[Pterodactyl_imp]

^^^^^. It is indeed an interesting read. In some respects counter intuitive. Have only skimmed it so I must give it more thought.

Cheers

[cbdtran_imp]

Today, it was my first ride with the Pirelli Sport Demon on wet roads ("normal" rain). To make a long story short: no, the Pirellis do not have as much grip on wet roads as my former Dunlops D205. In one 90° turn with approx. 40 km/h speed, the front tire started skidding a bit - it was not dramatic as skidding started slowly not abruptly so I was able to intercept.

Wet grip together with the - for me - too agile handling in curves seems that the Dunlop would be the better choice for me and my CB compared to the Pirellis.

this is the reason I always go with manufacturer's recommendation. I don't want to change something then find out I don't like it and have to live with it.

[ingobohn_imp]

Well... on my Transalp I had the Bridgestone Trailwings, and these default tires were really bad! The Metzeler Tourance or Michelin Anakee 3 were much much better.
So it is not always good to follow the manufacturer's recommended or by default delivered tires.

[Pterodactyl_imp]

Today, it was my first ride with the Pirelli Sport Demon on wet roads ("normal" rain). To make a long story short: no, the Pirellis do not have as much grip on wet roads as my former Dunlops D205. In one 90° turn with approx. 40 km/h speed, the front tire started skidding a bit - it was not dramatic as skidding started slowly not abruptly so I was able to intercept.

Wet grip together with the - for me - too agile handling in curves seems that the Dunlop would be the better choice for me and my CB compared to the Pirellis.

this is the reason I always go with manufacturer's recommendation. I don't want to change something then find out I don't like it and have to live with it.

For sure that's safe and I appreciate your point of view. In my case when it came time for me to change my D205s they were a "special order" and expensive. BT54s were no longer available so I went with BT45s, bias ply and not manufacturer's recommendation. I would say that, overall, they were a better tyre than the D205s. Handling good and better wear. When they needed replacement (I got about 15000+kms) I wanted to go back to radials. At this stage I became interested in CIP's views on the Michelin RP3s. OK, so I took the jump and 900kms later I have not regretted it at all. However, after reading ingobohn's report regarding the Pirelli Sport Demons I would do a lot more research before considering buying Pirellis. Front tyre breakaway in the wet is not good. I am surprised because review (revzilla et al) gives them 4.5/5 for wet traction. I would assume that he had a matching Pirellis front and rear. The best aspect of the Michelins, according to expert review, is wet weather performance. In other areas they are not the "best" but adequate for me. I really like the easy turn in - smooth as silk and then, leaned over, as sticky as a mouthful of peanut butter. The different profile when going over glass road eyes and small ridges is noticeable and initially disconcerting, but after some 900kms I have complete confidence in the Michelins. They just feel different.

In short I couldn't be happier that I have gone away from the manufacturer's recommendation. Over the next two weeks the CB's new shoes will get a good workout over a lot of good roads in the northern NSW coast and hinterland region. Probably around 3000kms or a maybe a little less. Bring it on!

Cheers