Track junkies jump in here-tire question

[Shibumi]

I had my rear tire trashed recently by my local dyno shop, so I decided to replace my Qualifier 190/50 with a 190/55 based on discussions I've read of better performance in the twisties. I've managed to get to 0 chicken strips on a bike lowered 1 1/2" so thought I would pursue further handling options...

How MUCH difference is there between the two? All I know is they are 0.6" taller in overall diameter, so I'm raising my rear 3/10ths of an inch.

Any quantifiable data, i.e. track times better or more lean possible etc? Contact patch X% bigger at full lean?

Or more of a "feel" difference?

I'm still less than a year out from being a bike virgin, so I'm curious what to expect different than the tire I've always ridden.

 

[Charlesbusa]

There is a bigger contact patch on the side of the tire with a 55.  A 50 has a bigger contact patch in the middle.

Not only is the tire taller it is just plain more tire, which means it is heavier.  That will rob just a bit of hp.

With the 55's profile, it takes less effort to lean the bike over and from side to side.  This makes the bike "feel" lighter.

Remember a tire grows as it gets hot.  So the rear will get raised up even more.

If you want to make your bike "feel" lighter, I recommend raising the rear an inch with dogbones.  This makes a big difference.

I love the 55 rear on the busa.  The busa has tons of power, so why not have more grip on the side of the tire rather than the middle.  Better to spin the tire while sitting straight up and down than at max lean...

 

[Charlesbusa]

You aren't going to find any hard numbers.

If you are riding faster and faster into corners, I think this is a good progression;
1)Set-up stock suspension for track use at your weight(may require stiffer front springs). Cheap
2)Then go to a 190/55 if you don't mind spending extra $ for side grip. Not that expensive
3)Then consider aftermarket suspension parts. Forking out $$$ once
4)Then race tires. Forking out $$$ frequently

 

[Shibumi]

Thanks for the info Charles!

I remember you saying you weigh about 165, I am the same size- is the stock spring sufficient for this?

Also I have the front lowered 1" with Pingel spacers, so raising the rear back to stock height will basically get me a short guys +1 conversion!

 

[Charlesbusa]

Problem with a lowered bike is ground clearance.

If you start scraping fairing, time to slow down a bit or raise the bike back up.

Stock front springs may have enough to get you to proper ride height. Even if they don't, at our weight you can get it very close and not risk bottoming out the suspension.

 

[pure_ego]

uhm... lets be honest here.. if you were REALLY concerned with cornering ability you wouldn't have lowered it (or atleast wouldn't have left it lowered) so what difference does it make?

I've heard good things about turn in from guys runnin 180's on the back (180/50 I assume) steeper profile so it "falls" into turns faster.. but slightly smaller contact patch also one would think

 

[BA BUSA]

(pure_ego @ Apr. 28 2007,22:41) uhm...  lets be honest here.. if you were REALLY concerned with cornering ability you wouldn't have lowered it (or atleast wouldn't have left it lowered)  so what difference does it make?

I've heard good things about turn in from guys runnin 180's on the back  (180/50 I assume)  steeper profile so it "falls" into turns faster.. but slightly smaller contact patch also one would think

Your assumption would be wrong 180/55...taller profile and larger contact patch than a 50 series

For the track 180/55's are better than 190/50's...and the 190/55's are even better

 

[BA BUSA]

Lowering won't necessarily hurt handling...but it will KILL your ground clearance.

 

[gtrpimp76]

Charles pretty much nailed it.

Another thing to put into account is that a 55 will raise your bikes ride height 7-10mm more than a 50 series. That alone is enough to make changes to your suspension and geometry based on those numbers.

 

[Tango1300]

I've been running a 180/55 since I changed tires last year, three sets ago... I won't go back. I love the way the bike pivots and the side grip is awesome with this heavy bike.

 

[Shibumi]

(pure_ego @ Apr. 29 2007,00:41) uhm... lets be honest here.. if you were REALLY concerned with cornering ability you wouldn't have lowered it (or atleast wouldn't have left it lowered) so what difference does it make?

I've heard good things about turn in from guys runnin 180's on the back (180/50 I assume) steeper profile so it "falls" into turns faster.. but slightly smaller contact patch also one would think

To be "honest" Ego, I'm 5'8" and lowered it so I could hold up a 500 pound bike at a stoplight. Not everyone lowers a bike so it will look "cool".

You know what happens when you assume...

 

[Shibumi]

(Tango1300 @ Apr. 29 2007,08:24) I've been running a 180/55 since I changed tires last year, three sets ago... I won't go back. I love the way the bike pivots and the side grip is awesome with this heavy bike.

How about a 190/55?

A negligible amount more rolling mass and more grip!

 

[pure_ego]

your arguement doesn't carry any water because I know several guys shorter than you riding bikes taller than the busa ever thought about being and having problems.... 5'6" with a vstrom for example. (the 1000.. not the 650)

but whatever makes ya happy dude.

I "assume" i offended your pride by stating the obvious so I'm sorry.

 

[Shibumi]

(pure_ego @ Apr. 29 2007,10:15) your arguement doesn't carry any water because I know several guys shorter than you riding bikes taller than the busa ever thought about being and having problems.... 5'6" with a vstrom for example. (the 1000.. not the 650)

but whatever makes ya happy dude.

I "assume" i offended your pride by stating the obvious so I'm sorry.

Yep, you know us short guys are touchy... look at Napoleon for example, sheeesh NOT a guy you want to piss off!

Seriously though, a lot of folks take flat-footing a bike for granted- you do NOT want to have issues balancing a bike as heavy as a Busa. I've tried it, and it definitely feels better when you can plant both feet at a standstill. I lowered mine before I learned anything about affecting handling for practical reasons only, and I've read many a post from others who have said the same. I bought a new Tobin seat which puts me closer to the ground, so now I can raise her back to stock height for better handling- that plus the 55 tire in back and turn-in should get much crisper.

 

[BA BUSA]

(gtrpimp76 @ Apr. 29 2007,02:50) Charles pretty much nailed it.

Another thing to put into account is that a 55 will raise your bikes ride height 7-10mm more than a 50 series. That alone is enough to make changes to your suspension and geometry based on those numbers.

Pretty much

Overall tire height on a 190/55 is 9.5mm more than a 190/50...but remember that not all tires measure
the same as they are rated. As for "ride height" it is only 1/2 of that 9.5mm...4.75mm  

 

[Shibumi]

(BA BUSA @ Apr. 29 2007,11:40)

(gtrpimp76 @ Apr. 29 2007,02:50) Charles pretty much nailed it.

Another thing to put into account is that a 55 will raise your bikes ride height 7-10mm more than a 50 series. That alone is enough to make changes to your suspension and geometry based on those numbers.

Pretty much

Overall tire height on a 190/55 is 9.5mm more than a 190/50...but remember that not all tires measure
the same as they are rated. As for "ride height" it is only 1/2 of that 9.5mm...4.75mm

Is 4.75 mm the same as 0.3 in?

You running a 190/55 or the 180?

I think they haven't been out very long- one website I looked at (Dunlop?) said it was made specifically for the ZX-14- do they come with this tire stock? If so, they did a heck of a lot better than tossing on a Battlax!

 

[BA BUSA]

(Shibumi @ Apr. 29 2007,12:15)

(BA BUSA @ Apr. 29 2007,11:40)

(gtrpimp76 @ Apr. 29 2007,02:50) Charles pretty much nailed it.

Another thing to put into account is that a 55 will raise your bikes ride height 7-10mm more than a 50 series. That alone is enough to make changes to your suspension and geometry based on those numbers.

Pretty much

Overall tire height on a 190/55 is 9.5mm more than a 190/50...but remember that not all tires measure
the same as they are rated. As for "ride height" it is only 1/2 of that 9.5mm...4.75mm  

Is 4.75 mm the same as 0.3 in?

You running a 190/55 or the 180?

I think they haven't been out very long- one website I looked at (Dunlop?) said it was made specifically for the ZX-14- do they come with this tire stock? If so, they did a heck of a lot better than tossing on a Battlax!

4.75mm converts to .187 inches

I have run both the 190/55 and a 180/55...190/55 is the best one to use, but it is also the most $$$.

Dunlop came out with their 190/55 for the '06 ZX10 (ZX14-190/50)

190/55's have been around for a while...it's just in the last year that more manufacturers are selling that size.

190/55's...all of these companies are making them...might be a few others also.

Pirelli
Metzler
Michelin
Bridgestone
Dunlop
Continental

 

[Don Hardcastle]

As soon as I need new tires mine is getting Corsa IIIs 120/70 front 190/55 rear. I should be able to dive into corners then

Don

 

[Don Hardcastle]

As soon as I need new tires mine is getting Corsa IIIs 120/70 front 190/55 rear. I should be able to dive into corners then

Don

 

[Cykill]

swapping to a 55 profole for a track/twisty rider makes a big difference. At lease i felt a big difference.

I use the Qualifiers. so far i really like them. To me they have a better feel, and just feel more stable to me than PPs. but both are good tires