[Busted4aWheelie]

Former motorcycle technician, and used to manage a tire shop for cars/trucks...

Looking at our front rim, the width is only 2.75" with a 110mm wide tire. All sportbikes that have a 120mm tire come with a 3.5" front rim.

So, in reality, we should have a 100/80/17. Almost identical circumference, and tread doesn't pinch to a nearly 90 degree lean angle like on the 110.

The benefit to a 100 over a 110? Well, aside from a more proper profile for the rim width, you have increased grip at lean, YES, I said INCREASED with a narrower tire. That's because as you lean on a 100, you tread contact patch is wider than the 110 because the 110 is too pinched.

Another benefit is the 100 is lighter by 1/2 a lb.

Why did they put a 110 on? To legitimize the bike. Idiots look at the size tire to judge it's performance potential. Smart people look at contact profiles. Since the smart people are in the minority, they manufacture to stupid people's standards...but rather than making the front rim wider which cost extra money and adds weight, they just gave us too big of a front tire to satisfy the squids. =(

So, IRC makes a 100/80/17, which I'll be putting on when I need a change, and running the Bridgeston Bt090 in the rear which is 3.7lbs lighter than the OEM IRC rear tire. And believe me, that much weight far from the axis of rotation (the rear axle bolt) you can DEFINITELY feel.

Stringent weight reduction on my old 636 Kawasai had it cluching up wheelies in 3rd gear on the freeway with stock gearing...normally unheard of, and these were NOT bouce up wheelies or standing on rear pegs, but sit downs!

Anyway, look into it.

 

[kiwi rider]

So did you put a 100 on in the end and how did you find it?

 

[Schroeder]

Do you really expect an answer of someone who hasn't logged in in over a year?

 

[kiwi rider]

im a patient man!

 

[isaacm12]

im a patient man!

Gave me a laugh for today, thanks lol

 

[BenjiFACE]

I'll hop on the waiting train

 

[isaacm12]

http://www.cbr250.net/forum/motorcycle-parts-sale/11161-brand-new-oem-windscreen.html

You guys might have to wait QUITE a long time... he sold the bike 4 months after this post was made.

 

[Arrethul]

Just throwing it out there, 110 is a more common size and easier to find. But hell, if someone really wanted to throw a 100/80 on, more power to them.

It would be pretty hard to get a nice matching set of tires using a 100/80.

 

[beefsalad]

Looking at our front rim, the width is only 2.75" with a 110mm wide tire. All sportbikes that have a 120mm tire come with a 3.5" front rim.

Stringent weight reduction on my old 636 Kawasai had it cluching up wheelies in 3rd gear on the freeway with stock gearing...normally unheard of..

Another benefit is the 100 is lighter by 1/2 a lb.

Why did they put a 110 on? To legitimize the bike.

I've had people try and blow smoke up my ass in the past. I'm not buying a word of what this guy says. Stringent weight reduction? Shervinrrr gave his ninja a stringent weight reduction...

I swore I wouldn't...but - Kawasaki ZX-10R.net
Oh my.... (unusual mods on a Green Kawi) - BARF - Bay Area Riders Forum

Or you can browse his gallery and let his pictures speak for his "skills"

https://www.flickr.com/photos/shervinrrr/


Additionally, places are listing the 110 as the proper size for the bike. Not enough evidence for you? Let's ask someone less partial....

http://www.mtsac.edu/~cliff/storage/gs/Motorcycle_Rim_Width_Tire_Size_Chart.pdf

110/70 is well within the realms of a 2.75" rim, but let's step away from that for a minute. 'All sportbikes that have a 120mm tire come with a 3.5" front rim.' So this guy knows all sport bikes? I doubt it! So let's have a look at my stable.

CBR250RR has 3" rim and 120mm tire. WRONG ANSWER JIM!

To his credit, my 919 does have a 3.5" rim and a 120mm tire, but my previous line clearly points out that he doesn't know everything. Sure, you can shove a 100 on the front of your CBR250R if you want. Much luck the previous owner of my CBR250RR managed to shove a 160 in the back. Did it work? Sure it did. The fact that the tire rubbed the swingarm to the point of melting the tire was more proof than I needed to show that it COULD fit.

Now let's look at another one of the lines he spat at us.

"Another benefit is the 100 is lighter by 1/2 a lb."

Great, a 1/2lb. Who here races their 250R at a level where a 1/2lb is going to matter? Yes, less rotational mass I agree. If I want to drop a 1/2lb before a race I'm going to evacuate my bladder and bowels. That's usually good for 2lbs.

Had enough of his BS yet? How about another!

"Why did they put a 110 on? To legitimize the bike."

I have never had anyone question the size of my tires or the legitimacy of my machines. If they did, they were smart enough not to say something to me about it. Now the size of the engine. Tons of people question the legitimacy of the bike based on the size of the engine. I've invited them all out to the twisties when they questioned the 'legitimacy' of having a 250 on the street. 0 takers I assume because I explain that the bike is light as hell, very flickable, enough power to get the job done, not so much power it's a handful if you do something dumb, economical in fuel economy and insurance. I've had a few people point out that it would suck as a touring bike. I'm sure it does compared to their connie/goldwing. But that's not why I got a 250R. If I wanted a touring bike, I'd be on an ST or Connie or something built as a tourer/sport tourer.

I feel like a jerk for tearing into this guy, but the smell of BS bothers me.

Disclaimer: I know what I know and not much more. If I'm wrong I'm wrong and feel free to point it out. You're not going to hurt my feelings.

 

[isaacm12]

@beefsalad His flickr made me laugh....
https://www.flickr.com/photos/shervinrrr/4063731182/

I think I need that aftermarket exhaust because my Coffmans doesn't breathe well enough.

 

[shisoshin]

pirelli, michelin and honda recommend and fit
110/70/17 front tyres for/to cbr250r..

including newly designed pirelli sport demons
and michelin radials, of interest on this forum..
according to pirelli australia national manager
sport demons in this size with this slightly
different tread pattern, were created for
cbr250r..

pirelli, michelin and honda have a combined
unparalleled technical and direct experience
in road and racing motorcycles and tyres..

the idea that honda would fit a wrongly sized
front tyre to its most recent all new designed
250 motorcycle is, well, laughable..

there are smaller width tyres, eg 90
for as honda moto3 racing fronts..

steering responses in cornering are effected
by more than simply width across the tread..
or for that matter relative percentages of
that measurement representing height..

my newish pirelli sport demons now run in
for eg, are this recommended size yet
turn in and quick steering responses
are obviously greater than the stock
tyres in the same size..

enough that i had to 'learn' the new tyres
which 'fall into' corners so easily
as to be almost an extension of
thinking the thought..

anyway, for what its worth, this member
also got a laugh at the idea of honda
needing to [somehow] 'legitimize'
this motorcycle by fitting larger
that necessary front tyres

 

[CBR-250-R]

I know, old post, but:

I'm looking for new tires for my cbr250r. So I found also this post.

Aside, that I would love, to try the 100 and 130 option on it, I think, I have to point on this:

"Why did they put a 110 on? To legitimize the bike."

I have never had anyone question the size of my tires or the legitimacy of my machines

The CBR 250 R is the direct competitor to the Ninjette and the Z 250 of Kawasaki. Both did come with a 130 rear!
And it was designed for the Asian markets. Here Honda has a CBR 150 R, for quiet a while.
And guess, the CBR150R comes with 100/80 and 130/70 tires.

So Honda had a 'need', to let the bigger bike look a bit bigger. At the rear also for the competitors, in the front, to give the 250 rider a bit more, as the 150 rider gets!

I'm trying, to convince a friend of mine, that she gives me her wheels for a day or two.
Trying all combinations,
100/130
100/140
110/130
110/140
could enlight these matter a lot!
But till now, she refuses my request.

Actually, I would probably buy/try a 130/80, in case the test is any good, for my rims with new tires, then.

Just my2cents

CBR250R

Edit: Went for oilchange, yesterday. With two Repsols, a CBR150R and a CBR300R side a side, I took pictures from the tires.
Honda needed the bigger size on 250/300. I'm still trying to find out, if the bike needs it, too

 

[bradmeister]

Oh, the Urban "Myths" about tires ............and the He said, She said, they said!

The OP seems to believe that Car and Truck tires (that don't bank and turn at 45 degrees Plus) are relative to motorcycling. Aside from proper inflation pressures and inspection, He may as well be contrasting and comparing Apples and Condoms.

TIRE SIZE HEIGHT AND DIAMETER for a "Sport Bike" Have already been engineered and proven many years ago. 17 inch with a 20-23 degree Rake is the MAX Factor for high speed turning and maneuverability.

Until another brain storm and break through like the Hossack Suspension adapted by BMW motorcycles comes along..........this is as good as it gets!

The Age Old question is not mixing and matching (which is a very ignorant thing to if not outright Dangerous) tires, but whether or not:

1. Do you want a sticky tire that has a great ride and performs (AS SHINOSIN MENTIONED) like an extension of your body but costs more????

2. Do you want a High Mileage tire that lasts for 7 years, is hard as a rock and transmits every road imperfection into your ass and costs less than half of a Sticky one????

Those are the only 2 Factors any Sport Rider should be considering........

Mixing and matching tires changes everything from wheelbase, to geometry to Center of gravity..... THIS IS NOT ORANGE COUNTY CUSTOM CYCLES ON TV.

If I was going to look at replacing my cracking IRC's tomorrow, I would jump on this Forum and Solicit Input from the Senior Forum Members for their input, Not the Manufacturing rep or the magazines!!!!

keep the sunny side up!

Cheers

 

[SpotTheDogg]

100/80 would be a nice option and a better fit