Finally moving from a 190 to a 180 rear tire.

[Justin726]

Well after 40,000 miles (all on 190 series rear tires), I'm going to try a 180 rear tire. I'm heading to Colorado in a few days and needed a new tire. I figured I'd try the 180 and guessed that the Colorado roads would be the best chance I'd get to take advantage of the difference. Hell, I might not even ride hard enought to tell a difference. Don't quite know what to expect. Guess I'll find out in a few days.

[Whymista]

Whats the purpose in going with a 190 vs 180?

Never really knew.

[Justin726]

I think it has something to turning better. Either leans into the turns better or better lean angle.....Some kind of bullshit like that.

[Whymista]

Mmmmm BS.

Yum

[Jyn]

Originally Posted by Justin726

I think it has something to turning better. Either leans into the turns better or better lean angle.....Some kind of bullshit like that.

You'll more than likely be happier with the 180. Unless you're a dedicated track rider, a 190 isn't necessary.

[kevin_stevens]

What size is your rear rim? I wouldn't go with a 180 on a 6" rim, would recommend a 190/55 profile instead. Makes a big difference and fits properly.

KeS

[Justin726]

Originally Posted by kevin_stevens

What size is your rear rim? I wouldn't go with a 180 on a 6" rim, would recommend a 190/55 profile instead. Makes a big difference and fits properly.

KeS

Dang, where were you a week ago when I ordered the bastard?

I'm pretty sure it's 6in rim. Whatever the stock rim size is. I know I've seen a lot of people over on the Hayausa Forums go to a 180. After this quick Colorado trip most of the rest of the tire life will get used up on the flatlands of Nebraska anyway. Not like I live on the sides of my tires like some people do.

[Gaolee]

A friend went from a 190 to a 180 on his 2001 GSXR 1000 a few years ago and immediately dropped a number of seconds from his lap times. I ran a 190 on my race bike last year, and I'm not convinced it would have made any difference if I had a 180 on the bike. Messing with the geometry made more of a difference - shortening the wheelbase a bit using sprocket sizes and lowering the front. You will probably like the 180, since it will improve turn-in unless you have a skittish bike. Then you probably won't like it as much.

[Joe]

It largely depends on what 190 profile you had.
The second number ie. 190/50/17 it's the 50 that determines the tire profile height, 190 being width, 50 being a percentage of the tire width determines the tire height.

The formula goes like this. tire width = A, tire profile height is a percentage number of a = B, actual profile height = C
A*B=C

The taller the profile height for a given with means quicker turn in


So a 190/50/17 would have a tire height of 95mm. (190* 0.50=95)
A 190/55/17 would be 104.5 mm (190*0.55=104.5)
A 180/55/17 would be 99mm (180*0.55=99)

^ that means both a 190/55 and 180/55 would both turn in quicker and also be a bit taller (which btw will increase spedo error)

Edit: there's more to it than that, but it gives you a fairly accurate idea of what happens with different sized tires on a given rim width

Edit 2: increase spedo error isn't right it'll decrease it

[Whymista]

Joe has brains?