Are these tires too old?

I got my bike that had been sitting and can tell you for sure that rubber gets harder with age and when it comes time to stop quickly the front tire will break free and skid. My bike tires looked great and after running them a month or two they are cracking. I thought the surface would wear and grab better. NOT! I am enjoying spinning the spit out them though and most of the hard stuff has come off of the back but not the front. Back tire not so big of a deal but the front???? Do you really want to risk skidding while trying to make an emergency stop??? Replace the front. I have gotten blow outs at 100 plus mile an hour on the rear from picking up nails no problem. I have had a tube spit on my back tire the ones that look so good from cali and rode it home before I noticed her wagging. The front tire going out where all the control is??? I pray to God that never happens to you me or anyone else I might know. Replace the front if not now after a week or two of serious riding you notice it crack and then you can take my word for it. Old rubbers are just no good to trust.

Regarding the following:

Yes your tires almost with 99.9999% accuracy have tubes but....
www.motorcyclecruiser.com/tech/tubeless_tire_seal/index.html

I was under the impression that tubless wheels have a different rim profile that provides a better seal than tube type wheels. Is this not the case?

So, this is interesting-

I just looked at the tires to see what size was actually on there (not sure why I didn't before).

The rear tire is already a 120/90-18 and the front is a 100/90-19.

Also, the rear tire, at least, is tubeless. Couldn't see very well to tell if the front is also or not.

The tire says tubeless but if it's on a spoke wheel (which it apparently is), I'll bet you a dollar against a donut that it has a tube in it

Most, if not all, tubeless tires made for the street can be used with tubes.

I posted a video in the Bike Related forum of a guy racing a KZ750 on 7 year old Bridgestone BT45 tires.

Also quality of the tire initially has some bearing too. A 10 yr old Dunlop GT501 will stick better than a brand new D404, so age is not all there is to it, and 10 yrs sitting out in the sun is way different than 10 yrs in a dark shed. I let my 1993 Ford van sit for 6 yrs out in the weather without moving. The tires were 10 yrs old at this point and the van and tires only had 7000 miles on them. They had 1/4" wide cracks in the sides but still held air. Sun takes a toll on rubber more than age.

saxjonz wrote:

Old rubbers are just no good to trust.

hahaha.

I'll say it again. lol Hell, my car is 2005 and has dry rot in the tread pattern. Tires for bikes are by design a bit safer than car tires. I have ridden my bike 3,000 miles on dunlops which imo are not the greatest tire to buy and they looked like new when I got the bike including the nubs on the tires but hard rubber is not as traction worthy as new rubber. I have ridden my bike and have smoked the rear tire quite a bit, all throttle mind you, going down the road I have hit it at 30 and got that bad boy to spin and leave a nice black patch on the road. After three thousand miles of tire smoking action they are just now starting to hook up a bit better. If you ride around town and don't get caught in the rain I wouldn't worry too much about it.
I ride in the city and there are many idiots who cut you off once one got in front of me and slammed his brakes. Both tires skidded when the front at least should have grabbed. Now picture that in the rain. Ride it awhile and see where it gets you.

I got to ask if these Dunlops are the D404s by chance? If so, yes by all means get rid of them. I did a long term test on them, if you can call it that. I guess 2 yrs and 5000 miles or so, and damn those tires get slippery when they get old. That's not the norm in Dunlop or tires in particular, but true on the 404s and I would assume comparable tires, Chen Shin type would be iffy when old too. Now if they are not 404s, what are they just for info. Of course K81s and stuff like that oem is also iffy, but Id be surprised if K591, GT501 and those better tires have any hint of problem. I threw the D404s and put on a K591 rear that's been sitting since the mid 90s and a 3.25-19 Continental on the front of the same age and it was like night/day the difference. 2 years on these tires now and no problem yet.
Just for info please. If old tires are dangerous I'm in deep crap because I just checked mine out.
1977 KZ650 Tires 2 yrs on the bike but 13 yrs old
1977 KZ650 Replaced in 1994
1978 KZ650 Replaced in 1994
1978 KZ650 Original
1979 KZ1000 Replaced in 1991
1980 KZ1000 Original
1974 H2 Replaced in 1993
On top of that these tires were probably "old" as I used to buy tires sometimes 6 or 8 at once and store them in the garage. State of the art 1930 garage though:laugh:

wiredgeorge wrote:

Check the rear wheel size again. I would think the rear rim was 18" and not 19" but I could be wrong as I have never owned a 750 twin.

You are correct.

Front: 3.25H-19 4PR

Rear: 4.00H-18 4PR

Metric equivs are:

100-90-19 Front

110-90-18 Rear

Like I said though, there is no metric equiv. Sure 110/90 or 120/90 *works*, but it's not equivalent. 120/90 beats 110 though if you need *equivalent* NOT, otherwise I'd recommend 4.00-18

I once asked a tire guy if I needed to replace my tires and he said "YES", so I asked, "There isn't any more life in these?" and his reply was "If you are thinking about your tire while riding, that's not a good thing to be thinking about. If you think they need replacing, replace them."

I've now lived by this rule for 90,000 miles of riding and only ride if I'm comfortable with my tires. I just replaced two tires last week that looked "Brand New" still had the nubs on the tread, but they were 6 years old a dry rotted.

So is there a performance difference between tubed and tubeless tires?