How often should tires be changed?

[nurider]

Got my '97 Kat last October. Original owner says he never changed the tires - 7 years!!!! The bike has 10k miles on it.

I think it's high time to get a new set.

Forgetting about obvious, visible signs indicating the end of tire life, are there any "rules" about how often tires should be changed?

BTW, I'm in PA.

Thanks.

[BISQ]

Several things to consider:

1) Your style of riding

2) The number of heat cycles your tires have been subject to

3) Tire cupping--common on Kats

4) Tire wear marks/bands

5) Change in tire profile due to wear, and the impact of that on your riding.

[WildKat]

Hey nurider..be sure to post up in the Intro. forum as well. Im in PA too..what part are you from ? We've got a ton of PA riders here.

Alot of it depends on how often you ride and how you ride, which determines how they wear...for example that last owner obviously didnt ride much, over 7 years...but you'll get some different answers depending on who you ask.

[nurider]

Oops. I thought I had posted an intro when I first signed up. Maybe not ...

'97 Kat 600 - first bike (hadn't been on a bike in 20+ years)

location is Allentown, PA

Between mid-October (when I bought it) and when I had to stop riding, courtesy of the weather, I logged about 1500 miles

Have at least some gear: helmet, textile jacket, summer/winter gloves, boots (am in the process of ordering textile pants).

Took the MSF course (highly recommended) BEFORE I bought my bike

[The CyberPoet]

Tire manufacturers say that motorcycle tires should be changed under the following guidelines:

(A) Five years from date of manufacture. This is the industry guideline for how long it takes the tires to lose the VOC's and the rubber to "harden up". Every tire has a date code stamped into the sidewall for this reason. Always check the date code on tires you are buying or just bought -- you don't want to buy a tire that's been on the shelf for several years already.

(B) For radial motorcycle tires, anytime the tire carcass gets penetrated, because of damages to the steel/kevlar/etc belts within the tire, which can cause localized heat-spots which may cause the tire to delaminate on the inside and result in a very nasty blow-out.

(C) Whenever the tire tread depth is less than minimum (usually considered 1.5 mm or 1/8th of an inch -- for Americans, put a penny in the groove upside-down; if the top of Lincoln's head isn't covered by the tread height, replace the tire).

(D) If the tire is no longer true that won't come out in a day or two -- such as if it has developed a serious flat spot from being parked in a single position for months/years on end. Tires should always be stored on their sides during storage for this same reason.

(E) If the tire has been overheated, often visible by discoloration of the tire carcass from black/dark gray into the blue or purple portion of the color spectrum.

(F) If the tire carcass has been damaged by acids, brake fluid, or long term storage on polyester fibers; this is often visible as discoloration from black/dark grey into the tan, white or light gray portions of the color spectrum.

(G) If the tire tread blocks are worn unevenly front-to-back (scalloping), which indicates the tire was run under ideal pressure and as a result ran too hot. There may also be non-visible internal damages such as delamination between the layers.

(H) If in doubt. Too much is riding on your tires to make running questionable tires worthwhile. Remember, a new set of good tires is still cheaper than the typical bill for the ambulance ride to the hospital, or the fairing pieces to repair a wrecked bike.

Cheers
=-= The CyberPoet

[nurider]

Thanks, CP.

The dry rot is a compelling enough reason to change the tires. I wanted to ask the question anyway.

Another question: does it generally work out cheaper to buy online and have the tires mounted somewhere, or to buy and have them mounted at the same place?

[nurider]

Regarding riding style:

I'm not leaning too far just yet. Hope to spend a decent amount of time riding this season, and that should change. No plans of going to a track, so the riding will mainly be roads/highways/twisty's.

[The CyberPoet]

Another question: does it generally work out cheaper to buy online and have the tires mounted somewhere, or to buy and have them mounted at the same place?

Depends on the local shops, their tire prices and their mounting prices. I've heard tales that in VA (or was it WV?), many shops won't mount tires from elsewhere. Around here, most shops charge a much higher mounting rate for tires you didn't buy from them, although a couple don't have that hang-up (and thus get my business).

Generally, tires are cheaper via mail-order, but you really need to shop around to find the best prices. americanmototire.com just shipped me out a pair of Metzeler Z6's (120/70 + 150/70) for $187 plus shipping... That was enough of a savings to justify buying them online by all means

Cheers
=-= The CyberPoet

[trinc]

(G) If the tire tread blocks are worn unevenly front-to-back (scalloping), which indicates the tire was run under ideal pressure and as a result ran too hot. There may also be non-visible internal damages such as delamination between the layers.

Cheers
=-= The CyberPoet

i disagree. read this

http://w6rec.com/duane/bmw/cupping/

tim

[The CyberPoet]

(G) If the tire tread blocks are worn unevenly front-to-back (scalloping), which indicates the tire was run under ideal pressure and as a result ran too hot. There may also be non-visible internal damages such as delamination between the layers.

Cheers
=-= The CyberPoet

i disagree. read this

http://w6rec.com/duane/bmw/cupping/

tim

Perhaps I should rephrase it:
If severe scalloping occurs on a Katana (greater than about 1mm in tread height between the leading edge of one tread block and the adjacent trailing edge of the previous treadblock), and you can feel it as feedback at the handlebars, then I believe the tire should be replaced. Obviously we're talking about traditional street tires for our Katana purposes and not knobbies used on BMW GS-series bikes; for knobbies, such wear is normal because of the large spacing between tread blocks.
Two brands that I know of tend to do this heavily on the late model Kats here in Florida (and only these two to my knowledge): Michelins and Dunlops. The average road temps here (and resultant tire temps), and the long-distances at high speeds which I tend to ride may well play into it.
If your Kat's tire is severely scallopped, it can also reduce the total contact time per revolution, thus increasing braking distances, among other issues; this alone would dictate considering replacement in my mind.

Cheers
=-= The CyberPoet

[nurider]

Shuold I be looking at harder tires since there won't be much racing involved in my riding?

[trinc]

(G) If the tire tread blocks are worn unevenly front-to-back (scalloping), which indicates the tire was run under ideal pressure and as a result ran too hot. There may also be non-visible internal damages such as delamination between the layers.

Cheers
=-= The CyberPoet

i disagree. read this

http://w6rec.com/duane/bmw/cupping/

tim

Perhaps I should rephrase it:
If severe scalloping occurs on a Katana (greater than about 1mm in tread height between the leading edge of one tread block and the adjacent trailing edge of the previous treadblock), and you can feel it as feedback at the handlebars, then I believe the tire should be replaced. Obviously we're talking about traditional street tires for our Katana purposes and not knobbies used on BMW GS-series bikes; for knobbies, such wear is normal.
Two brands that I know of tend to do this heavily on the late model Kats here in Florida (and only these two to my knowledge): Michelins and Dunlops. The average road temps here (and resultant tire temps), and the long-distances at high speeds which I tend to ride may well play into it.
If your Kat's tire is severely scallopped, it can also reduce the total contact time per revolution, thus increasing braking distances, among other issues; this alone would dictate considering replacement in my mind.

Cheers
=-= The CyberPoet

i pointed to that page because it has a good description of what is happening to the tread block - reguardless of knobbie or street - the force applied to the individual thread block is the same. if you look at tires that are prone to this effect you will notice that the tread pattern ( grooves ) segments the tire into a lot more blockes.

i cupped my crapadams & my 010's and i'm religious about running 33 psi, i ride in a lot of technical areas - so when i up the pace, i brake hard & alot !

but my point wasn't the replacement - but that the root problem was tire pressure.
tim

[The CyberPoet]

Shuold I be looking at harder tires since there won't be much racing involved in my riding?

If you tend to rail (i.e. - knee down, canyon or track riding), I would advocate grabby tires, such as the Pirelli Diablos. If you don't tend to rail, I would recommend sport-touring tires, which combine a degree of grabbiness with a longer-life expectancy, and are engineered to match the type of motorcycle you are riding (the Katana is a sport tourer).

Personally, I like the Metzeler Z6's, Z4's and think you would also probably be served very well by the Bridgestones and Avons as secondary choices if you have problems finding the Metzeler and Pirelli's in the appropriate sizes for your build-year and rim-width.

Cheers
=-= The CyberPoet

[nurider]

If you tend to rail (i.e. - knee down, canyon or track riding), I would advocate grabby tires, such as the Pirelli Diablos. If you don't tend to rail, I would recommend sport-touring tires, which combine a degree of grabbiness with a longer-life expectancy, and are engineered to match the type of motorcycle you are riding (the Katana is a sport tourer).

Personally, I like the Metzeler Z6's, Z4's and think you would also probably be served very well by the Bridgestones and Avons as secondary choices if you have problems finding the Metzeler and Pirelli's in the appropriate sizes for your build-year and rim-width.
[/quote]

Many thanks.

[1BlueKat]

I run the Maxxis on my Kat, and I always maintain 40psi, is this going to shorten my tire life. I have read that a lot of folks run 33 psi.