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Old 02-26-2019, 04:56 PM   #16
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I did not inspection the spot after. It was dark and I thought I had just asked more from the tire than it was willing to give.

On a later day I inspected the tire at home looking for clues.

After that, and what I've read here, I wish I had inspected the pavement. I might do it later in the week during a dry (to better see tire marks) day time.

I'm fine. No injuries.

A few years ago I bought D30 hip armor, maybe to install in my Roadcrafter. It would have been good if I'd done it. I didn't see any scuffs on the Roadcrafter.

The OEM plastic head protector on the BMW might be adequate if you tipped a parked bike over, but not up to a brief slide. At least not the 12 years old one that was on there.

I typically run 38 PSI in the rear, but I had had this tire installed the day before, and the higher pressure I mentioned in the 1st post is how it was set. I had thought about checking it in the morning, but didn't. If this is all about running over something sharp, that's irrelevant. But if it's disappointing performance from a cold, new tire, I guess it could be a factor.
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Old 02-26-2019, 06:32 PM   #17
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I typically run 38 PSI in the rear, but I had had this tire installed the day before, and the higher pressure I mentioned in the 1st post. But if it's disappointing performance from a cold, new tire, I guess it could be a factor.
This!.......
The day before?
All new tires need to be broken in..

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Old 02-26-2019, 06:46 PM   #18
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Running 41 psi in the cold is most definitely going to have something to do with what happened. That's simply to high. And a brand new tire? It will be extremely slippery until it's scuffed in.

PS: Never leave a tire at "the pressure it was set at." That's inflation pressure. The guy making $15 hourly mounting your tires knows NOTHING about you, or your needs. If it were me, I'd be hesitant to ride that rear over 36 psi, and probably go lower.
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Old 02-26-2019, 07:42 PM   #19
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What are the manufacturer-recommended pressures?
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Old 02-26-2019, 08:34 PM   #20
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Running 41 psi in the cold is most definitely going to have something to do with what happened. That's simply to high. And a brand new tire? It will be extremely slippery until it's scuffed in.

PS: Never leave a tire at "the pressure it was set at." That's inflation pressure. The guy making $15 hourly mounting your tires knows NOTHING about you, or your needs. If it were me, I'd be hesitant to ride that rear over 36 psi, and probably go lower.
in 2012 I attended a tire seminar at Road Rider, given by then Pirelli/Metzeler brand rep, tire engineer Ron Bowen (IIRC). He had us touch the surface of a new tire, and feel how slick it was (while explaining how new tires are slippery). He also said to set sport touring tires are sidewall maximum pressure. Which I may have done at least in the rear tire for awhile after, but later went down a bit.

The Continental tire has the Traction Skin™ feature where the virgin surface is textured and not slippery to the touch. I'd had the front for awhile, and it did everything I've asked of it. And I took the rear close to the edge on the other side on the trip from the tire shop back to work. It's possible I started believing in Traction Skin™ more than I should have.

I expect fast warm up from sport touring tires--maybe I should be more careful with that expectation. I've had ones that disappointed (including a HWM tire that was on the rear of the R when I got the bike that for me never seemed to warm up at all on cold rainy days), and it's possible this one has less cold grip that I expected. It won a recent tire comparo for dry grip, and that might come at a cost in cold grip or warm up time.

I think I'll try it at 36PSI.

I haven't ridden that bike since, but may commute on it tomorrow.
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Old 02-26-2019, 10:02 PM   #21
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I think the cuts on the tire happened as the bike went down, or after the bike went down and slid. The cuts are the result of going down, but not the cause. Some surface roughness on asphalt could easily do that as the edge of the tire of a downed bike skidded along.

Blaming the tire and moving on means you've learned nothing. 40.8 psi may be a little high and may reduce traction, but that's still no reason for a low-side. Traction is always a variable, so expect/assume something to the point of crashing the bike means a different approach should be considered.
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Old 02-26-2019, 10:50 PM   #22
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Some surface roughness on asphalt could easily do that as the edge of the tire of a downed bike skidded along.
If you think the >1mm deep gouge in the tire that followed the direction of rotation as lean increased is from the bike skidding along, you're mistaken.
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Old 02-27-2019, 07:21 AM   #23
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I had a friend go down on 84 when he crossed water. He immediately blamed his Shinko tire. I explained that the other 3 of us had gone through the same water at least 10 mph faster than he had. His tires could have been made of wood and he wouldn't have crashed if he hadn't target fixated on the water and stabbed the brakes. It took some time having him go over his thoughts and view to get him to understand what he did. The tire was not the problem. The rider was.

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Old 02-27-2019, 08:56 AM   #24
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in 2012 I attended a tire seminar at Road Rider, given by then Pirelli/Metzeler brand rep, tire engineer Ron Bowen (IIRC). He had us touch the surface of a new tire, and feel how slick it was (while explaining how new tires are slippery). He also said to set sport touring tires are sidewall maximum pressure. Which I may have done at least in the rear tire for awhile after, but later went down a bit.

The Continental tire has the Traction Skin™ feature where the virgin surface is textured and not slippery to the touch. I'd had the front for awhile, and it did everything I've asked of it. And I took the rear close to the edge on the other side on the trip from the tire shop back to work. It's possible I started believing in Traction Skin™ more than I should have.

I expect fast warm up from sport touring tires--maybe I should be more careful with that expectation. I've had ones that disappointed (including a HWM tire that was on the rear of the R when I got the bike that for me never seemed to warm up at all on cold rainy days), and it's possible this one has less cold grip that I expected. It won a recent tire comparo for dry grip, and that might come at a cost in cold grip or warm up time.

I think I'll try it at 36PSI.

I haven't ridden that bike since, but may commute on it tomorrow.

Sport touring tires at sidewall recommendation is ludicrous. That's a liability recommendation.
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Old 02-27-2019, 10:17 AM   #25
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Sport touring tires at sidewall recommendation is ludicrous. That's a liability recommendation.
Im surprised that person wouldn't just say "manufacturer specs". those tend to be lower than max while also taking into account the weight of the motorcycle, which is tons better than max pressure.
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Old 02-27-2019, 10:27 AM   #26
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Oddly enough my NC700X says 36f/42r whether solo or 2 up. The rear is significantly higher than I'd expect to want to run, and higher than I run.
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Old 02-27-2019, 10:30 AM   #27
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If you think the >1mm deep gouge in the tire that followed the direction of rotation as lean increased is from the bike skidding along, you're mistaken.
Are you, then, implying you were leaned over to almost the edge of the tire on a low speed (public) turn? You said it yourself in the OP, that you did not have that much lean angle, in which case those gouges must have occurred after you lost traction, not before.
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Old 02-27-2019, 04:50 PM   #28
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Max pressure? You betcha and then some.

http://cyrilhuzeblog.com/2011/06/03/...f-the-week-27/

A good case for solid tires. I think Rubbermaid has them.

On the serious side, once you lose confidence in the tire that is kinda it. Correct other things by all means but no matter what, confidence lost in a tire is hard to overcome.

A change in tire gives you a fresh perspective and lets you reflect on other contributing factors. By eliminating that one variable it allows you to focus your concentration.

The gouges look like cuts, not abrasion except the one feather. The feather could have resulted from the slide but the cuts happened from running over something or impact, not sliding, IMMHO.

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Old 02-27-2019, 11:39 PM   #29
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I typically run 38 PSI in the rear, but I had had this tire installed the day before, and the higher pressure I mentioned in the 1st post is how it was set. I had thought about checking it in the morning, but didn't. If this is all about running over something sharp, that's irrelevant. But if it's disappointing performance from a cold, new tire, I guess it could be a factor.
Cuts like that are common when a tire spins up and slides. It doesn't indicate that you ran over something sharp that made you fall down.

This scenario is a typical cold/new tire crash. You had the tire installed, didn't check the pressures, hadn't leaned it over very far on that side yet and had only ridden a half mile when you crashed. No tire is going to give its best grip under these conditions.

Your combination of lean angle and opening the throttle was too much for the condition at the moment. If you happened to be turning the throttle while adding lean angle, that can make a rear spin a lot sooner than if you set the lean angle before rolling on the gas.

The correction for this is to approach break-in and warmup with a little more caution. Scuff new tires gradually by progressively adding lean angle in successive turns. The contact patch in each of these turns should consist of some already scuffed rubber and some new. Be disciplined about this.

If you're in the habit of turning the bike quickly, turn in a little more slowly for the first few turns when tires are cold. If a tire slips, this makes it a little easier to catch than with a quicker turn-in. Once tires are warmer and you can predict traction, it's safe to turn more quickly.

Finally, be sure to separate turning in from rolling on the gas. Doing both at the same time is a time tested way to provoke a slide at much less lean angle than you would expect. Set the lean angle before you crack the throttle open.

It may ease your mind to replace the tire, but I think you'd come closer to addressing the cause if you correct some of the above.
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Old 02-28-2019, 07:57 AM   #30
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