Tire size benefits

HokieRider

HokieRider

Member
ok, i just bought a designated track bike (02 R6), and the guy who had it before me gave me ALOT of extra tires.

the stock tire size is a 180/55 in rear and 120/60 in front. all the spares he gave me were 190/55s and 120/70s

is there any benefit/deficit to running tires like this? he said he had run them on the bike several times so im not sure

thanks
 
rk97

rk97

Member
I would prefer to stick to stock sizes unless it's the Dunlop 211 "190" that is really more like 185, and made for 600's.

IF that's the case, then I understand running the 120/70 to compensate for the rise in rear ride height. Just watch that the 120/70 doesn't rub on your front fender. I had that issue on my old bike. It really depended on what brand of front fender you had more than anything.
 
HokieRider

HokieRider

Member
I do in fact have extras. Most of them are pirellis. I also think I have a set of Michelins and maybe a set of dunlops.

Hotbrakes, PM me
 
Meat

Meat

Member
You should also be able to run the Dunlop 195 slicks on your 600 as well without any problems, if you so desired.
 
LesPow

LesPow

Control Rider
I had a similar question....I recently put the 190 60x17 Dunlop AMA spec tire. I had to add links to my chain to get it fitted properly, the bike feels taller for sure.
By adding the links to the chain I'm wondering if the wheel base has lengthened thus affecting handling, or should I be making adjustments to bike set up to better take advantage of this tire? Or just ride the damn bike?
Oh yeah, and it had a bad tearing along the right side much the same as the soft compound 209's everyone suffered with when they came out. It was colder in the morning, and maybe I need more preload...???
 
JRA

JRA

New Member
The 190/60's are awesome. I tried one out at Barber last month and it felt just as good to me as the UK 6680 slicks I've been running. I didn't change a thing either.


I got good wear out of the 5436 (med) compound. Check the code on the sidewall to see if you had a medium or soft. Also, what was the air temperature?
 
Meat

Meat

Member
Rasta;241136 wrote: I had a similar question....I recently put the 190 60x17 Dunlop AMA spec tire. I had to add links to my chain to get it fitted properly, the bike feels taller for sure.
By adding the links to the chain I'm wondering if the wheel base has lengthened thus affecting handling...
Click to expand...
In adding links, that means that you had to change sprockets. Was the tire rubbing the swingarm?

And yes, changing the swingarm effective length can affect how the bike handles. Someone that actually understands more about it will have to explain the effects.

You can also always complicate the matter by also considering the swingarm angle relative to the chain. The angle of the chain, relative to the ground also changes as gearing changes which impacts how much downward thrust is applied to the rear tire (when accelerating) and when.

I'm too slow for small chain angle changes to make any difference to me.
 
rk97

rk97

Member
The simple explanation for wheel-base changes affecting handling is an extreme example:

A top rotates (turns) easily because it has a single point of rotation. The closer together your front and rear tire are, the more they share the qualities of a single point.

By contrast, a longer wheel-base (bus or limo in an extreme example) is less willing to rotate, and requires a larger area to make a turn without pinching the apex.

With a bike, it's only a few millimeters of change, but the effect is still there, albeit at a much less pronounced degree.

A larger rear tire would actually change the fork angle (more upright) and shorten the wheel base slightly in the process.
 
LesPow

LesPow

Control Rider
jra..i set the tire pressure hot on warmers 21 rear, 31 front going to check but I think it is a medium compound
meat...no I did not change the sprocket size, I went from 190/55/17 to 190/60 and it rubbed on the swing arm so had to add links.
 
LesPow

LesPow

Control Rider
@ jra you asked air temp, not pressure so it was around low 60's in am going up to 74°f...
 
some guy #2

some guy #2

Member
I have no idea on stock geometry for 600rr's. If the axle is in the same place the bigger tire adds some mm to the overall so you might want to push the wheel further in. Honestly I'd just ride it and see how it feels.
 
nk140

nk140

Member
Rasta;241205 wrote: jra..i set the tire pressure hot on warmers 21 rear, 31 front going to check but I think it is a medium compound
meat...no I did not change the sprocket size, I went from 190/55/17 to 190/60 and it rubbed on the swing arm so had to add links.
Click to expand...
I have a 05 600rr. I had to add links to my chain as well to get the big NTEC slicks to fit or I had to run a smaller rear sprocket than I wanted to. On my bike it doesn't rub the swingarm it rubs the shock linkage. When I lengthened my chain I didn't really notice a big difference but I have been running it that way for a season now and I was too slow back when I changed to notice anything.
 
denbsteph

denbsteph

Member
I have a similar question as well, it was suggested I go to a 70 (from a 60) upfront to get more patch contact, but it was also added that if I go to the 70 I will need to change the geometry, add some shims to the rear shock or drop the front forks down. At VIR over Easter weekend Chuck set my sag up with Dunlop Q2's 180/55/17 and 120/60/17, I rolled without issue's at VIR the entire weekend, S/N.

My concern is if I get the 70 do I need to change the geometry as suggested?

If I do change the geometry, I will screw the suspension set up that Chuck did.

Has anyone else changed from the 60 to the 70, using the STOCK fender without issue?

I do have a HOT BODIES front fender, anyone running a DUNLOP Q2 120/70/17 with that fender without issue.

All this is on a 07 R6S.

Dennis
 
JRA

JRA

New Member
I think almost everybody went to a 70 front tire on that bike. You might have to make a slight fender mod to make sure it clears, but running a 70 front will be worth it as you have many more options and a better tire. If you wanted to change the geometry just measure from the ground to the axle center before and after switching tires and you'll then know how much you actually raised the front.

Rasta, I was wondering about ambient temperature in regard to cold tearing. I experienced no tearing at all on a 5436 rear and had excellent grip with moderate wear at Barber.
 
LesPow

LesPow

Control Rider
@JRA Def. cold tearing, did not expect a medium to tear. A soft yes, but it also happened to my buddy even worse for him same day same tire, and wore better as the day heated up. At the time I was convinced it had to do with his suspension setting. Thanks to all for their thoughts on this.
 
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