55 profile in the back. Ok... but why?

[connie14boy]

The first rear tire I bought after the 021 Crapstone was a PR2 50 series profile which was a great improvement, but still needed a little handle bar imput (correction) in fast sweepers. After reading in the forum about the 55 series, I next bought a PR2 55 and voila, the bike handled like on rails, and what I was expecting and hoping for all along with this bike. Also, the speedo is more accurate when checked with my GPS. I think a 55 rear tire profile is what is best for this bike, but Kawasaki was probably scared about the additional 3/8" seat height which requires a 32" or longer inseam. I now have a PR3 55 series and lovin' it too.

[jwh20]

The first rear tire I bought after the 021 Crapstone was a PR2 50 series profile which was a great improvement, but still needed a little handle bar imput (correction) in fast sweepers. After reading in the forum about the 55 series, I next bought a PR2 55 and voila, the bike handled like on rails, and what I was expecting and hoping for all along with this bike. Also, the speedo is more accurate when checked with my GPS. I think a 55 rear tire profile is what is best for this bike, but Kawasaki was probably scared about the additional 3/8" seat height which requires a 32" or longer inseam. I now have a PR3 55 series and lovin' it too.

connie,

Did you put a 190 or a 180 on the rear?  I've heard a lot more positives elsewhere on 180 vs. 190 than 55 vs. 50.  Michelin does make a PR2 in 180/55.

Just curious.  Thanks.

[gPink]

180  has a rounder profile and is cheaper than a 190

[tomp]

And I did say "reading low", what I meant there is just what you said, your speed is lower than indicated.  So I guess the speedo actually reads high.  For some reason every motorcycle I've ever owned does this.  If you check it with a GPS, which is extremely accurate, you're always going slower than indicated.  Is this a way of fudging the top speed or something?

Speedometers are almost always set optimistically.  I've had some bikes with a constant 10% ratio.  Others, not so radical, or almost a variable ratio difference, depending on the speed being travelled. 

Was told that auto and motorcycle manufacturers do this to avoid any litigation from owners who get stopped for excessive speed violations.  No way a claimant can accuse the auto/cycle  of reading a lower speed than they were actually traveling, blaming the maker for the error, not their lead foot or wrist... 

Made sense to me, when I heard it. 

[B.D.F.]

Well, just to balance out the entropy of the universe, I want to say that I notice quite a difference with the /55 series tire size and like the change.     There we go- three people, three opinions and they are all different. I do not think I have ever seen that before on a motorcycle forum.... 

The 55 series just works better on this bike, at least for me, in all conditions and speeds. In addition to handling, it brings the speedometer closer to correct (although it still reads a tad low) and brings the engine RPM down just a bit at the same speed. Not much of a consideration for most people probably but I have been known to spend more than a couple of hours droning down the [seemingly endless] highway and engine speed / noise is fatiguing.

The only downside that I can think of is that it seems that the 17-190/55 tires are a 'lot' heavier than the 17-10/50 tires. Unfortunately that is just my take from changing a bunch of them; I have not weighed a tire of any brand in either size so really do not know. But the /55s do seem quite heavy to me and un-sprung weight on a bike is usually not a good thing. On the other hand, the C-14, for all of its performance and relative nimbleness really IS a weight pig anyway so the extra weight, if there really is much, is not a deal- killer for me.

Brian

I couldn't tell the difference..

Yup, it's like a jack-up kit for the back of the bike, which changes the rake of the forks. This makes the turning a little more aggressive.

I could, but not in a positive way. I tried the 55 series rear tires, twice, and didn't like them. I just found it made the bike feel like it had a bigger tire on the back...lol. On a good note, the 55 series tires do have a higher load rating and do last a little longer, at least in my experience.

Rem

[connie14boy]

connie,

Did you put a 190 or a 180 on the rear?  I've heard a lot more positives elsewhere on 180 vs. 190 than 55 vs. 50.  Michelin does make a PR2 in 180/55.

Just curious.  Thanks.







I've always used the 190- 50/55. Didn't think about the 180 until you mentioned it, but maybe next time.
Here's another tidbit:
The stock rear 021 Crapstone went 5,500 sufferable miles before I dumpsterized it.
The Michelin PR2 190/50 went 12,300 miles before it's demise.
The Michelin PR2 190/55 went 16,700 miles before it was done- a real winner in my book!
There you go, to me there's no downside.. only a small initial cost increase over the 50 series Michelins.

[tomp]

Wonder why KHI went with the 50 vs the 55 series, as OEM?  Was it the slight weight savings that Brian mentioned?  possibly to slow down initial turn in, that some with 55's state ?  Or possibly to the to place a WIDE profile tire, as throughout the last decade, FAT tires were the Thing to have?   Or just maybe, Bridgestone has a b*tt load of 50 series they wanted to dump on the market, and KHI took advantage of great pricing?  Could be something else entirely, but we will probably never know. . .

FWIW, how many remember the cool little Bridgestone bikes of the late 60's, early 70's?  Great scoots, and innovative, too.  Why can't they do the same for their tires? 

[Conniesaki]

[tomp]

Are those general profiles or when mounted to the same width wheel? 

[connie14boy]

Wonder why KHI went with the 50 vs the 55 series, as OEM?  Was it the slight weight savings that Brian mentioned?  possibly to slow down initial turn in, that some with 55's state ?  Or possibly to the to place a WIDE profile tire, as throughout the last decade, FAT tires were the Thing to have?   Or just maybe, Bridgestone has a b*tt load of 50 series they wanted to dump on the market, and KHI took advantage of great pricing?  Could be something else entirely, but we will probably never know. . .

FWIW, how many remember the cool little Bridgestone bikes of the late 60's, early 70's?  Great scoots, and innovative, too.  Why can't they do the same for their tires? 


[/quote

Wonder why KHI went with the 50 vs the 55 series, as OEM?  Was it the slight weight savings that Brian mentioned?  possibly to slow down initial turn in, that some with 55's state ?  Or possibly to the to place a WIDE profile tire, as throughout the last decade, FAT tires were the Thing to have?   Or just maybe, Bridgestone has a b*tt load of 50 series they wanted to dump on the market, and KHI took advantage of great pricing?  Could be something else entirely, but we will probably never know. . .

FWIW, how many remember the cool little Bridgestone bikes of the late 60's, early 70's?  Great scoots, and innovative, too.  Why can't they do the same for their tires? 




I can only relate the bad Bridgestone experience to their crappy 021's- and mostly it's the front 021 that is the worst- I think it's made of compressed cardboard/animal byproducts and glue. That being said, I understand that there are other Bridgestone bike tires that are decent- but I am more than thrilled with my PR's and am stickin' with 'em.

[maxtog]

Everybody has mentioned the handling pros and cons.  How about the benefit of the 55 correcting the slow speedo. This alone I feel is worth going bigger.

Yes, but it also raises the back some, which is a huge negative when you are trying really hard to get short legs to the ground

Remember guys... Size does matter

I thought it was not the size of the ship but the motion of the ocean...

[maxtog]

your speed is lower than indicated.  So I guess the speedo actually reads high.  For some reason every motorcycle I've ever owned does this.

Actually, you will probably find that *EVERY* vehicle will be this way, stock....  regardless of vehicle type, model year, or brand.  Why?  Because it is my understanding that manufacturers are required to be no more than X% reading high, but can't be at ALL low.... so they have to err on the high side to be safe.

Update:  Of course, I posted this and THEN saw Tomp's posting above, saying nearly the same thing.  Oh well, great minds think alike

[tomp]

I thought it was not the size of the ship but the motion of the ocean...

Is that a nautical quote?  I'm sure sailor_chic knows about what she is saying.  It just leaves me out of the game, that's all.

Isn't that what I said about speedometers, too.  Great minds do think alike, and post over one another, too. . . Ain't life grand?!?!

Seems we've gotten of track, once again.  basically think of a buy back as a used bike with possibly a crappy title, to boot.  Wait, that is another thread that is also off track.  Use the tire that feels best to you...  How's that?  Also, if size is ever brought up to you, lie to her, I mean LIE...

[Rhino]

Actually, you will probably find that *EVERY* vehicle will be this way, stock....  regardless of vehicle type, model year, or brand.  Why?  Because it is my understanding that manufacturers are required to be no more than X% reading high, but can't be at ALL low.... so they have to err on the high side to be safe.

Update:  Of course, I posted this and THEN saw Tomp's posting above, saying nearly the same thing.  Oh well, great minds think alike

Both my 2011 Nissan Titan and 2013 Ford Escape the speedo is right on the money. Matches a gps exactly.

[maxtog]

Both my 2011 Nissan Titan and 2013 Ford Escape the speedo is right on the money. Matches a gps exactly.

They were that way from purchase with stock tires? Pretty amazing.  I have never had a vehicle that matched GPS speed.  Had one that was close, though, like 1MPH or so over.

[tomp]

FWIW, I've always heard/read that the exact accuracy of a GPS usually happens over a long distance of straight unencumbered road, where the GPS and satellite can communicate uninterrupted.  The Garmin, on my 04, never equalled my speedo, nor did the speedo or the GPS of my friend's 12 RT, ever match mine or his speedo.  Both are Garmins, and used same satellite,  but got different readings.  Go figure. 

Most accurate is the radar gun the LEO is pointing at you, as they are calibrated every day before they are placed into service.  Served on local juries, where folks fought their speeding tickets.  Needless to say, each ticketed person lost. . .

[aspire61]

I asked the same question last spring when I changed from a 50 to a 55 tire. I considered a larger tire would turn slower, therefore not giving you as much of a self-stabilizing  or gyroscoptic effect. I couldn't garner much support since some assumed a larger wheel would turn faster.

After a season of riding, I think it has more to do with the narrower contact area on the pavement, as has been suggested by others.

mat

[tomp]

61,  Happier  with the 55 or the 50?

[Conniesaki]

Are those general profiles or when mounted to the same width wheel?

Dunno, I didn't make it. Just passing on "information" of unknown-to-me origin and accuracy, which is what I thought the internet is all about  Well, that, and porn.

I've seen it quite a few times on various forums (the graphic, that is), usually related to (supposedly) making a bike turn better. It seems logical to me, I think, and many online dudes seem to like them ... but I do wonder why all manufacturers then don't just put a 55 on at the factory. Some do, most don't. Maybe that's the next small incremental improvement step in motorcycle evolution, and manufacturers don't wanna blow their wad. Then again, maybe a 50 profile is a better compromise between comfort / cruising and sports riding.

[tomp]

Dunno, I didn't make it. Just passing on "information" of unknown-to-me origin and accuracy, which is what I thought the internet is all about  Well, that, and porn.

I've seen it quite a few times on various forums (the graphic, that is), usually related to (supposedly) making a bike turn better. It seems logical to me, I think, and many online dudes seem to like them ... but I do wonder why all manufacturers then don't just put a 55 on at the factory. Some do, most don't. Maybe that's the next small incremental improvement step in motorcycle evolution, and manufacturers don't wanna blow their wad. Then again, maybe a 50 profile is a better compromise between comfort / cruising and sports riding.

Honest answer.  Ride what makes you happy, 50/55/60, whatever.  I still have over half the tread left on my 50, so I guess I will worry about this after a few thousand miles of happy riding... tp