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Discussion Starter #1
Is anyone running a 180/55/17 or 190/55/17 and what if any adjustments did you have to do for the two tires sizes. I'm tried to decide what sizes to go with.
 

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I did the same as Chip lower my forks to the first line and the rear is raised like 8mm
 

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If you don't mind me asking what advantages did you get out of lowering the front and raising the back end. Just curious if its something I should do to mine.
 

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If you don't mind me asking what advantages did you get out of lowering the front and raising the back end. Just curious if its something I should do to mine.
Lowering the front end and/or raising the back end slightly reduces the rake and trail. That makes the bike turn quicker.
It also makes the bike a bit more unstable due to less trail (or caster in car terms).
Don't go crazy with these adjustments. Make small adjustments and test.

Another way is the add a shim to the rear shock mount.
You can change the thickness of the shim to vary the ride height change.
You can also do likewise by changing out the lower shock link with the Kyle Racing lower link.

Also remember that not only does the 190/55 have a more ogival (pointed) profile over the more evenly round 190/50, but the 190/55 also is a taller tire by a few millimeters.
This too will effectively change the rake/trail by a small degree.

Plus, tires heights vary from the manufacturer for the same "size" tire.
Each time I've change brands, I've measured the circumference and the overall height can be different for front and rear depending on brand/model of tire.

For instance the 120/70-17 Conti RaceAttack Street is 296.6mm radius and the rear is 323.9mm.
The Dunlop Sportmax Q2 120/70-17 is 301.6mm radius and the 190/55-17 rear is 321mm.
So just switching from Continental to Dunlop caused a 5mm raising of the front end and a 2.9mm drop in the rear for an effective change of 7.9mm.
It doesn't sound like much, but it will affect your handling.
That's why it's recommended to measure your tires when you change brands.
 

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Discussion Starter #11
I just order the Conti RaceAttack Street 120/70/16 front and 190/55/17 rear. How are those tires on the RC I didn't know much about them and research them prior to buying on ebay. I was ok with the purchase as the price for both was very reasonable. I'm changing from the dunlop qualifiers 120/60/17 front and 190/55/17 rear which came with the bike. Will this change affected the bike in any serious manner.
 

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You're going from a 120/60-17 front to a 120/70-17?
Offhand I'd say yes, you will probably have some handling changes requiring adjustments.
Unless that's one tall 120/60 front tire.
 

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Discussion Starter #13
ok the tires came in a set with the 120/70/17 front and I thought the RC came from the factory with a 120/70/ thats why I buy that size front. What adjustments i'm I looking at and will it be worth have that size front
 

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Well let me back pedal a little and say you might need some adjustments.
Once you have your tires mounted, ride it and see how it handles.
It it suits your needs, then no tweaking required.
The Cont RaceAttack Street was the shortest tire I've mounted so far.
It may be close to what your previous 120/60 front was in handling.
Oddly enough, the Conti RaceAttack Street 190/55 rear was the second tallest tire I've mounted, beat out by the Bridgestone BT-016 190/55 which is my tallest tire yet.

I tried the Conti RaceAttack Streets when Pirelli cranked up the price on the Corsa III beyond my price threshold.
They're a good performer, but are slick on the sides so be careful in the wet.
I had tried the SportAttacks and really liked them. A good price/performance tire matched by the Bridgestone BT-016. And they worked pretty good in the rain.
 

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Discussion Starter #16
Had my Conti Sport Attack tires mount this weekend 120/70/17 and 190/55/17. The handling is different with the 190/55/17 rear, riding from the shop home was an adventure. After about 45 miles or so I had gotten use to the handle. The tire seem to ride fine and handle great. I may consider lowering the front a little.
 
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