Tire wear

[Old Bob]

Who rides their tires past the wear bars?  I find a little slip with tires getting close,(1/16 ") to the bars. Drop the pressure 2 lb.

andI think it helps a little, or I'm just imagining it.

 

 

[johnmark101]

I will ride the rear down to the wear bar, and a little beyond.  Once I reach the wear bars I ease up just a little but not much, and they grip just fine.

[peteinpa]

I'll run the rear down to just seeing the cords. Inspect after every ride. No slipping.

[1moreroad]

I change tires just before I reach the wear bars and right before a big trip. I change tires maybe once a year and getting even another 1000 miles (not sure that I would) isn't worth me worrying about it. If I could get another 1000 miles per tire, it has added up to the cost of 1 tire since I bought the bike in 2015.

[Old Bob]

The rear is to the bars, the front a little past with the sides somewhat shredded,(twisty mountain roads here in Nor Cal).  I'm putting on Michlein 5's, rain starting in a few weeks and I want security.

[DavidS]

I'm with 1moreroad, I replace my tires before I get to the wear bars. I'm more than happy to pay the cost of a new set of tires, and have no interest in testing the outer limits of any tire I put on my bike.

[PhotoAl]

Haven't worn a set of tires down to the wear bars in a long time.  I take long trips and generally need a new tire to make the distance - not going to risk the tire wearing out with 1,000 miles to go.  

Last trip was 6,200 miles and running a Road 5 rear with Power 5 front.  Lots of pretty straight roads getting out west but then lots of great fun in Montana and Wyoming.  Spent a lot of time in the curves.  Never got close to the edge of the tire but certainly wore the soft part of the tire!  Tire is amazingly rounded and not so flat in the center considering the number of miles going straight.

Seems like the front always has some scalloping wear from aggressive braking and I wind up replacing it before it is worn out but get 1 front to two rears.

[betoney]

8 hours ago, PhotoAl said:

Haven't worn a set of tires down to the wear bars in a long time.  I take long trips and generally need a new tire to make the distance - not going to risk the tire wearing out with 1,000 miles to go. 

I think I have mentioned this before but since you do a lot of trips maybe consider a 2nd rear wheel.  If you still have 1-2,000 miles of tread left on a tire but have a 5,000 mile trip coming up, no need to throw away a tire with life left in it.

I bought a used rear wheel on eBay earlier this year and had one wheel with a sport tire mounted and the other with a sport touring mounted and would swap wheels if a trip was coming up.  When I got back from a trip I would swap wheels and use up the remainder of the tread on local rides before getting a new tire installed.

[PhotoAl]

yes, have thought about it but not pursued it.  Another reason to get a 2nd set of wheels is could get them balanced before using.  My front is a fair bit out of balance so wind up with more balance weight on tire installation than I'd like.

[bwringer]

My usual rule is that if a worn tire is going to be on my mind or causing any shred of doubt, I replace it.

Quality radial tires handle and grip just fine past the wear bars; there is some loss of traction with a worn tire, especially in the wet, but that has more to do with the rubber compound nearing end of life through repeated heat cycling. 

Tire age in service is also a factor. I usually wear out at least two sets a year on each of my bikes, but if not, I don't let a tire stay in service more than about two years. Three years in service is the usual rule of thumb. 

There's little reason to obsess over date codes, although some people do. If a street tire was manufactured sometime in the last year or two, it'll be fine. In-service date is what's important; when did the tire start experiencing heat cycles?

For example, on my vintage bike, a 1983 Suzuki GS850G, I replaced the tires in the spring of 2020. I rode a lot fewer miles than usual in 2020 because of, well, you know, and I generally don't ride it as much as my other bikes. So although they have a bit more life left, I'll replace the tires on my Suzuki this fall or in the spring of 2022. 

And of course damage and potential damage is a factor. As a tire gets thinner, the likelihood of punctures gets higher. I just replaced the rear tire on my FJ-09 even though it had a few thousand miles left in it. I have one more long trip planned this fall, and the tire has had a plug in it for about 2,000 miles. 

Edited October 4, 2021 by bwringer

[Ride On]

Nothing to do with bikes, but my previous employer's standard operating practice, and as written in our Crew Resource Manual, was to let the tires wear down through the first set Kevlar cord on the tires.  Once the second, opposing cords were visible the tire had to be replaced.  And this was on an airline passenger jet.  FAA approved.

The wear was never completely uniform around the tire.  The Kevlar that would show would usually be silver dollar in size, maybe in a couple places around the tire.  Most of the wear occurs from the tires spinning up from zero to 175 mph at touchdown.

Seems odd for sure, but completely safe.

[Fleng]

2 hours ago, Ride On said:

Nothing to do with bikes, but my previous employer's standard operating practice, and as written in our Crew Resource Manual, was to let the tires wear down through the first set Kevlar cord on the tires.  Once the second, opposing cords were visible the tire had to be replaced.  And this was on an airline passenger jet.  FAA approved.

The wear was never completely uniform around the tire.  The Kevlar that would show would usually be silver dollar in size, maybe in a couple places around the tire.  Most of the wear occurs from the tires spinning up from zero to 175 mph at touchdown.

Seems odd for sure, but completely safe.

Just to make things clear, you are talking about the reinforcement plies, not the carcass. No reinforcement plies are used on motor tires, so don’t mix this up.

As a Airline Landing Gear engineer, I do know.

Edited November 11, 2021 by Fleng

[Old Bob]

2 hours ago, Ride On said:

Nothing to do with bikes, but my previous employer's standard operating practice, and as written in our Crew Resource Manual, was to let the tires wear down through the first set Kevlar cord on the tires.  Once the second, opposing cords were visible the tire had to be replaced.  And this was on an airline passenger jet.  FAA approved.

The wear was never completely uniform around the tire.  The Kevlar that would show would usually be silver dollar in size, maybe in a couple places around the tire.  Most of the wear occurs from the tires spinning up from zero to 175 mph at touchdown.

Seems odd for sure, but completely safe.

When the rubber is gone, so is the traction on any type of tire.

[Fleng]

On aircraft tires, there is still rubber when a reinforcment ply is visible. But wearing to the carcass is not allowed for obvious reasons..

[Wintersdark]

Aaaah, tires.  Everyone has their own strongly held opinions about tires.  

Personally... I never run tires down to wear bars.  Not because I feel you shouldn't, but because I've never had a set of tires last to the wear bars without aggressive acceleration and braking causing terrifically bad scalloping that destroys ride quality long before I run right out of tread.  I've not found a good solution here short of not pushing my bikes so hard, and, well, that's not going to happen.  Further, I swap to winter tires every fall, and summer tires every spring, so I've traditionally been very reluctant to pay someone to put old tires on my bike that I'll just need to replace in a couple months.  Now I've got my own mounting machine, however, that'll likely change. 

If this wasn't the case?   I'd run them to the wear bars, or until close enough to the wear bars before a longer trip.  Sure, you can get more mileage out of them - particularly if you're not riding in rain - so long as you've got rubber all around you should have decent grip on dry pavement.  But I REALLY don't want to have to change tires mid-trip, and I'm not so strapped for cash that I need to run risks on my tires.  YMMV, of course, but I do dumb things on my bikes, and I'd rather not die because I tried to squeeze a couple extra miles out of a tire.  If you're not doing dumb things, not pushing tires hard, I'm sure they'd be fine.  After all, all so many people I've known wear tires down to seeing metal and they don't seem to be crashing left and right.  

As @betoneysaid above, I'd REALLY love to get a second set of rims, but I've not found an opportunity to do that yet.  I'd need to find a set here in Canada, with rotors and sensor wheels, and I'm still unsure exactly which rims are actually compatible.  Shipping wheels from the US would be insanely expensive.  I would LOVE to be able to just swap out rims to run a new set of tires for a trip, then put the old ones back on to run them out afterwards, without a huge hassle actually spooning tires on and off.  Or summer and winter tires, etc. 

[hr] (edit: Hey, when did my wonderful Horizontal Rule bbcode stop working?)

Date codes lead to people having ridiculous notions like that "tires should be replaced once they're five years old" meme which is entirely unsupported by tire manufacturers themselves.  Specifics vary, but according to Dunlop, Michelin, Continental, Bridgestone, and Avon, the *shortest* tire life any mention (Avon) is 7 years.  Dunlop, for example, allows 5 years of shelf life where the tire can still be sold as a new tire, and 10 years from the manufactured date code where they will still honor their warranty.  I should note, that's up to 10 years in service, too, but realistically that's unlikely to happen.  Michelin warranties for 6 years from date of purchase, only looking at the date code if there is no proof of purchase. If curious, I looked this up recently after Ari Henning's video, and got the manufacturer recommendations for each of these, and have links for all of them.

Overall, the industry standard is 10 years from manufactured date as a maximum, but with tires being monitored for flat spots, rot, cracking, etc from 5 years on.  I feel this has to be a conservative judgement if anything, as it's in the tire manufacturers best interest for you to replace tires earlier rather than later.  

@bwringer is definitely correct though that environment is king.  Tires stored out of direct sunlight in an at least reasonably temperature controlled environment will last a very long time, while tires inflated on a bike just sitting in the sun and weather but not run are going to be garbage in short order.  Which is where date codes become kind of problematic.  I wouldn't hesitate at all to mount and run a "new" 7 year old tire that's just sat on a shelf in a warehouse, but the tires mounted on that old non-running "project bike" I picked up are gonna be replaced before I do anything other than just short test runs around the block.  

Edited November 11, 2021 by Wintersdark