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However, I want to point out that tire heat cycles (how often you heat and cool your tires) also plays a significant role in how fast your tire rubber breaks down. He mounts 7 y/o tires that have never been used or "new old stock". That's not the same comparison from a tire that has 2k miles on it with 500 heat cycles and sat for a year through Michigan weather.

Use your judgment by inspecting your own tires. I use my thumb nail and push it into the tire to gauge how sticky the tire feels. This tells me how soft the compound is and how much grip the tire may have. Try this the next time your looking at tires at your local shop but don't forget that some tires have a harder middle compound.

If I have old tires on my bike by date code only, they're not dry rotted, cupped, or showing any other signs of tire damage, I'll treat them as a brand new set of tires. I'll take them out and purposely scrub them in as I warm them up over time. I'll come back and check them out. If the color and soft rubber is starting to come through then I would consider them perfectly fine for street use. I wouldn't drive 3 hours to a track day with tires older than 5 years. Even though they don't have a minimum age requirement track day organizations do go by the appearance of total wear (50% or more) or "bluing" of the tire. I haven't been to a track day lately but it would be in your best interest to not give the inspectors a reason to flag your tires. They have tire vendors onsite a lot of the time and they don't hesitate to send them business. I certainly won't blame them for that. It's their track day and they can run it however they see fit especially when it pertains to safety.
 

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That was a great video and answered all the questions I had when I watched it. I had a relatively new front Q3 the had cracks around the circumference of the rim and when I had a new one mounted he told me he'd seen that happen when someone does a quick heat cycle and parks the bike for an extended time (months) which is exactly what I did. The new set he put on has been on 2+ years and has plenty of heat cycles and no issues so far.

My concern with new old tires would always be if the tire looks fine but after riding is starts to quickly deteriorate before you can stop safely and inspect.
 

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That was a great video and answered all the questions I had when I watched it. I had a relatively new front Q3 the had cracks around the circumference of the rim and when I had a new one mounted he told me he'd seen that happen when someone does a quick heat cycle and parks the bike for an extended time (months) which is exactly what I did. The new set he put on has been on 2+ years and has plenty of heat cycles and no issues so far.

My concern with new old tires would always be if the tire looks fine but after riding is starts to quickly deteriorate before you can stop safely and inspect.
Tires that are relatively new just don't fall apart unless there is a defect in the manufacturing. If they're not dry rotted, cupped, or blued, then you should be fine. They may require a little scrubbing in to get back to some good rubber but just take it easy for a few miles like new tires. I cringe at the tires that I rode on as a teenager back in the 80's and 90's on my 1978 Suzuki GS-400 and my 1986 Yamaha FZ600. Do you really think tire technology was better back then? I didn't EVER check my tires before I rode somewhere. So anything you do today to be proactive in keeping tabs on your current tires is far better than what I survived decades ago.
 

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Modern silica-based tyres don't heat-cycle and degrade like old rubber-black tyres. Lots of common tyre ideas were outdated since 1990s, but haven't faded away. One comparison test is to overcome traction limits of old tyres. Then installed new tyres of exactly same model and go back out and compare lap-times. Also tracking data over time is useful tool.

BT-45 on my commuter bike with date-code 2009 finally wore out in 2020 with 16K-miles. They were already 9-yrs old when I got bike. With many trackdays tossed in when my racebike was down for maintenance. Last sessions on them were just a bit faster than 3 years earlier.

Alpha-13-SP on by track bike went for 49 track-days over 2-yrs. They were already 5-yrs old when I got them. My last trackday on them setting PB times at Laguna Seca. Overheated them plenty of times before then too!

Many, many sets of Q3+ for free from ex-AFM MotoAm racer kids. I'd get over 45 trackdays on them with close to 1000 heat-cycles. Last laps on them usually faster than starting ones.


EXHIBITS
BT-45 that came on my commuter, 9-yrs old at time I picked up bike. By 16K-miles and 11-yrs old, they had some minor sidewall cracking, but still gripped just fine. Predictable limit behavior with gentle catchable slides.


Alpha-13SP, MotoAm specific version, slightly softer than regular Alpha-13
These were found at back of trailer when they cleaned it out. Was 5-yrs old when I spooned them on

By time I wore them out 2-yrs later, they had over 5000 laps and about 1000 heat-cycles in them. Set fastest PB lap @ Laguna Seca on them at very end of their life. :)

Overheated front-tyre plenty of times in +100F heat of summer @ Thunderhill. After cooling off, they came back and gripped just fine.


GP-A Pro D207, before I got into racing, I did about 10-yrs of trackdays on my '05 RR. Got these 6-yr old tyres from AFM racer. Oil-slick look on surface is caused by heating-up tyre but not really riding very fast to wear it. Commonly seen with newbies using tyre-warmers on sticky-tyres, but they ride at beginner pace. Very dangerous because sticky-tyres may have high-grip limit, but extremely sudden breakaway behavior with no warning when you go over limit. This guy would've been better off with more intermediate street-tyre, like Q2 at the time. After my 1st session, no more oil-slick and warmers not really needed.


That's another aspect of modern silica-based tyres, they actually warm up quickly and not need warmers. Michelin has nice trackday slick that doesn't need warmers, similar to Q4. It really only helps save 1 warm-up lap for racers who can take warmers off and get onto track right away. For trackday folks, with all sitting around waiting for track to clear, tyres will have cooled off to pre-warmer temps anyway. First couple laps should be easy to warm up tyres anyway. After which time, tyres will be up to temp regardless if they had warmers on before getting on track.

I think it's better to gauge tyre's condition rather than age as predictor of grip & safety. You can get old tyre that's in great unused shape, or brand-new one that's been improperly stored at too low and too high temps and end up with horrible performance. A durometer was helpful with old carbon-black tyres, but not that useful on newer silica-based tyres because compound doesn't dry out and harden with age.

As with any tyre, you'll want to take it easy at 1st, especially for winter-riding. Warm them up with brisk straight-line acceleration and hard braking. Then after couple miles, you can add some cornering. And take it up to limits of cornering gradually. This technique will let you find safe limit of any tyre, regardless of age or condition. Only difference will be speed when they start sliding.

Most crashes are caused by mistakes 1st, such as line-selections through corner. And then secondary result of that is overcoming tyre's limit by panic braking or overcorrecting steering/leaning. It's not tyre's fault. Very few people ride fast enough to overcome traction-limits of dry-rotted cracked rubber anyway. :eek:
 

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I'm glad you chimed in with your recent track experience. I wasn't sure how strick they had gotten lately but it sounds like they require the same tech as always. I'm speaking of Sportbike Tracktime. Not sure who you're using out west.

We seem to have a similar philosophy on tires. The only reason I would care about the date code is for warranty. Not condition. I'm currently running a rear D209 from 2009.
 

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In 2017, I bought a 2008 Suzuki B-King that still had the factory tires on it with only 3189 miles. Bike was garage kept with a cover over it. I rode the bike until the tires were worn out at around 6500 miles. Never had a n issue. Tires even held 42 psi without having to constantly air them up. Tires showed nothing bad at all, no dry cracks or anything.
 
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