What speed rating is on your tires?



FloydV

Donating Member
Registered
My apologies for a double post. I thought I was on a different web site (duh).

My Bridgestones are marked 190/50ZR17M/C (73W). That would make them good up to 168 mph, not 186 mph. Please correct if this is wrong.

This is from the website: Tire Tech Information - How to Read Speed Rating, Load Index & Service Descriptions

While a Z-speed rating still often appears in the tire size designation of these tires, such as 225/50ZR16 91W, the Z in the size signifies a maximum speed capability in excess of 149 mph, 240 km/h; the W in the service description indicates the tire's 168 mph, 270 km/h maximum speed.
225/50ZR16 in excess of 149 mph, 240 km/h
205/45ZR17 88W 168 mph, 270 km/h
285/35ZR19 99Y 186 mph, 300 km/h

Most recently, when the Y-speed rating indicated in a service description is enclosed in parentheses, such as 285/35ZR19 (99Y), the top speed of the tire has been tested in excess of 186 mph, 300 km/h indicated by the service description as shown below:
285/35ZR19 99Y 186 mph, 300 km/h
285/35ZR19 (99Y) in excess of 186 mph, 300 km/h

As vehicles have increased their top speeds into Autobahn-only ranges, the tire speed ratings have evolved to better identify the tires capability, allowing drivers to match the speed of their tires with the top speed of their vehicle.


Does anyone have tires with a number and the letter Y in parentheses?
 

Dweezel

Registered
I know all the Shinko's I've seen (they may make Z rated, not sure) are rated 'W' I believe. I'm running a 003 on mine and I'm really happy with it, but if I was going to push the 160+ mile marker I'd definately invest in the safety of a Z rated tire.
 

Blazing-Saddle

"Kowalski"
Donating Member
Registered
I know all the Shinko's I've seen (they may make Z rated, not sure) are rated 'W' I believe. I'm running a 003 on mine and I'm really happy with it, but if I was going to push the 160+ mile marker I'd definately invest in the safety of a Z rated tire.

I have Shinko 005s on both ends of my ride and they are are rated Z but also have the W for the 168MPH rating.

Rear tire: 200/50ZR17 M/C 75W Further around the tire is this: Max Speed 270 KM/H (168MPH) Same goes for the front tire as far as speed ratings go.
 

dewie

Registered
I've topped out with my shinko 003, over 300k what ever that is in MPH.. And I'm still here to talk about it.
 

WWJD

Donating Member
Registered
I've run many Z rated tires to the 185 mark with no trouble. Granted I am not STAYING up there for long thanks to running out of road. So I would not recommend extended high speed runs on Z, but there is not much selection out there as far as speed ratings for cycle tires
 

jwcfbd

Administrator
Registered
120mph ::11 The dealership put on the wrong tire and I found out on the way to work on the highway. They replaced my fender, gave me my money back, bought me the right tire and paid another shop to install it for me. :cheerleader:

HPIM0289 (Medium).JPG


HPIM0288a.jpg
 

FloydV

Donating Member
Registered
There are no Y rated D.O.T Motorcycle tires,trust me I know.
I believe you. I called Michelin and Pirelli. No Y rating and no 186 mph rating.
So what do racers use? It seems odd that a manufacturer would put 168 ceiling tires on a bike that can easily break 185.
 

FloydV

Donating Member
Registered
120mph ::11 The dealership put on the wrong tire and I found out on the way to work on the highway. They replaced my fender, gave me my money back, bought me the right tire and paid another shop to install it for me. :cheerleader:
Wow! And people wonder why no one trusts dealerships. You have to wonder what else they got wrong that just hasn't fallen off yet.
 

HillbillyTom

Donating Member
Registered
Z rating on my Michelins. I always read that the "Z" rating was for a "sustained" 149mph, but safe for short trips into the twilight zone above 149mph.
So far I havn't had a chance and enough clear road to try the theory out, but that's the way I understand it.
 

Gixx1300R

Registered
I believe you. I called Michelin and Pirelli. No Y rating and no 186 mph rating.
So what do racers use? It seems odd that a manufacturer would put 168 ceiling tires on a bike that can easily break 185.
There are tricks that can be doe to a tire to make it live at 250 mph. I use a hard compound to the tire stays cooler longer. Shaving rubber off of the center also helps.
 

FloydV

Donating Member
Registered
Z rating on my Michelins. I always read that the "Z" rating was for a "sustained" 149mph, but safe for short trips into the twilight zone above 149mph.
So far I havn't had a chance and enough clear road to try the theory out, but that's the way I understand it.
I've made quite a few trips into the twilight zone (180), but I didn't realize that the tires were Z (xxW) good to 168 and not Z(xxY) good to 186. I think the reason is that there are so few bikes that can hit that speed. Manufacturers don't see a profit in it.

Still, people who race here and abroad must use different tires. Where do they get them?
 

Busa1166

Donating Member
Registered
120mph ::11 The dealership put on the wrong tire and I found out on the way to work on the highway. They replaced my fender, gave me my money back, bought me the right tire and paid another shop to install it for me. :cheerleader:
::11 Sounds like they did everything they could make things right for the wrong they did.

but:wtf: were they smoking when they were working on your bike.
 

Gixx1300R

Registered
Running Z rated tires up to 200 mph is fine. It is when you approad speed in excess of 230mph and up is when it gets scary.

Picture400.jpg

Picture401.jpg
 

jwcfbd

Administrator
Registered
::11 Sounds like they did everything they could make things right for the wrong they did.

but:wtf: were they smoking when they were working on your bike.
That was the same thing I was thinking. They never saw my bike again after that one.
 

CTA_Busa_LE

Donating Member
Registered
not sure I want to know the story behind those pics, looks like a bit of a tense and rough ride back down to 0 for sure.
 

turbobusa2000

Registered
Do you guys remember the video recentlyof the bike that Dave Owen (RIP) built, I think it went 253 at maxton. Dave wasn't driving and I can't remember the name of the guy who did. Anyway, I remeber him saying what was done to the bike and I believe he said he was just running Michelin street tires. Can anyone confirm that. I know the vid is on here but I'm working so I cant view it. If that guy can go that fast on a Michelin street tire, I think will be ok doing 200 on a Z rated tire.
 

Gixx1300R

Registered
Do you guys remember the video recentlyof the bike that Dave Owen (RIP) built, I think it went 253 at maxton. Dave wasn't driving and I can't remember the name of the guy who did. Anyway, I remeber him saying what was done to the bike and I believe he said he was just running Michelin street tires. Can anyone confirm that. I know the vid is on here but I'm working so I cant view it. If that guy can go that fast on a Michelin street tire, I think will be ok doing 200 on a Z rated tire.
Yes that is correct. Guys there is nothing to worry about with you tires.
 


Latest Bikes

Forum statistics

Threads
173,706
Messages
3,110,206
Members
48,069
Latest member
Matthew turner
Top