190 Rear!

W@zzA · Post by **W@zzA** » Tue Aug 31, 2004 11:32 pm

Well I'm giving the freebee 190/50 rear tyre a go I bought a matching 010 bridgestone for the front and I have to say that I'm quite impressed, If it's any slower turning in I can't notice it! When I chew up this one I'll try a 180/55 010 so I can get a good comparison between the same tyre but different size. I'll let you know in a few months!

Warren

Stratman · Post by **Stratman** » Wed Sep 01, 2004 9:39 pm

I guess being a 50 profile this will reduce the gearing a bit over the 55. Interesting to hear how you get on. Any mathematicians able to work out the reduced gearing, 'cos I reckon this is = to a 15 t front sprocket at least?

Stormin Ben · Post by **Stormin Ben** » Thu Sep 02, 2004 1:02 am

190/50 = 95mm high
180/55 = 99mm high

Wheel: 17" x 2.541 = 432mm

Diameter difference = 437 / 441 = 0.991

Or about 0.4 tooth UP on the rear

God I must be bored!!

Ben

delmeekc · Post by **delmeekc** » Thu Sep 02, 2004 1:58 am

you didn't take into account the tyre expansion due to centrifugal force at varying speeds and that the 190 section will expand in circumference more the the 180 due to the increase mass and width.

Del (

errrrrrrrrrrr)

must go to bed earlier

I ran a 180 and a 190 (not together) and the 190 was better, had a lot more stability in the corners, those where the days.

(currently running a maxxis goldspeed on the rear and a 17" MT21 (rear knobbly) on the front, errrr.

MDJ · Post by **MDJ** » Thu Sep 02, 2004 12:35 pm

didnt I read an article in a tire test stating that the better tires showed no messurable deflection at speed?

Stormin Ben · Post by **Stormin Ben** » Thu Sep 02, 2004 12:42 pm

I think it depends on the tyre, some are better/worse than others

I currently run Bridgestone 010's and they fit fine.
However, I have another set of wheels for track days that have had Dunflop 208GP's and Metzeler Rennsports on (180/55 size)

Both of these have fouled the hugger, the Dunplops at 0mph and the Rennsports at 50mph plus
So either some of the tyre manufacturers' rulers need calibrating or . . . .something else - sorry lost the plot there

Ben

W@zzA · Post by **W@zzA** » Thu Sep 02, 2004 1:34 pm

Yep it's lowered the gearing and it doesn't foul the hugger in fact theres more clearence because of the smaller dia, I was advised against it but gave it a go cos it was a free tyre and I'm impressed with the results!

Warren

thehazmatguy · Post by **thehazmatguy** » Wed Sep 22, 2004 7:22 pm

I can't believe nobody has mentioned this, or I guess I could be horribly wrong:

the 190/50 rear tire was designed for a 6 inch wide rim.

the 180/55 rear tire was designed for a 5.5 inch wide rim.

If you put a 190/50 on a smaller rim, you aren't going to get the same measurements that are listed above. The tire is going to be pinched, with a peak in the middle. This will effectively raise the rear and give the feel of faster turn in. In a straight line you aren't going to have the same amount of tire on the road.

For example, everybody knows that the early TL1000's were prone to have some headshake. The poor mans cure was to go from the stock 190/50 rear to the 180/55 because, on a 6 inch rim, it lowered the back of the bike.

thehazmatguy · Post by **thehazmatguy** » Wed Sep 22, 2004 7:33 pm

More:

I used to work at a motorcycle shop, and I had to explain this to people all the time. Grrr.

More info here: http://www.sportrider.com/tech/tires/146_0206_size/

STEVESTORM · Post by **STEVESTORM** » Wed Sep 22, 2004 9:14 pm

THE NUMBER U LOT NEED IS LISTED UNDER s-a-m-a-r-i-t-a-n-s...
this isn't the normal 'size of rubber talk' we're used too - i know its under 'bike'chat' but really

delmeekc · Post by **delmeekc** » Thu Sep 23, 2004 9:07 am

the hazmatguy,

more. I used to work in a motorcycle shop, doh, now nobody is going to listen to ya.

straight line = now thats wot riding a bike is all about.

DEl.

dkt1376 · Post by **dkt1376** » Thu Sep 23, 2004 8:32 pm

i dont meen to sound anti about tyresize changes but honda spend Â£Â£Â£Â£Â£Â£Â£Â£Â£Â£s on testing bikes in all weathers conditions and on all surfaces and they deem that the vtr should run a 180 rear so why would u want to change it. i work as a bike tyre fitter and i will never advise people to change the tyre size from standard. i think that there must be somthing wrong with the way u ride or your bike if u think that putting a bigger tyre on will make u ride better.
sorry to rant but am i alone in this way of thinking

delmeekc · Post by **delmeekc** » Thu Sep 23, 2004 9:43 pm

dkt1376

so you don't think changing me 3.5" front rim to a 3" one and fitting an MT21 Rallycross rear tyre on it and changing me 4.5" rear to a 4.25" and fitting a Maxxis GoldSpeed 160 rear was a good idea then.

Surely though as tyres manufactures differ (as you should know all the 180 tyres have a different shaoe when fitted to the same rim) that it's personal preference. I had a 180 on the rear on me vtr with a 6.25 rim which was ok when running a track compound tyre but was sh1t on a touring tyre and was ok for rast road riding but no good on the track as you would end up right off the edge easily. So i changed it to a 190 rear which was better suited to the track but has a bit less rubber/road contact when cranked right over.

Del. (I am serious too mate about the MT21 etc but probably talking shite there after, no change then)