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Old 02-24-2019, 05:11 PM   #1
davidji
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Low sided. Not sure I can trust this tire.

I low sided on my R1200R the other day at low speed, and not that much lean angle, on a brand new, cold sport touring tire. The gouges I see in the tread surface have me doubting this tires capabilities.

Situation: making a left turn from a stop sign. Tire pressure measured at 40.8PSI. Ambient temperature 49-50F, and I'd ridden 1/2 mile before the crash. I had a total of about 70 miles on the tire from new. It had been over near the other edge, but not very far on the left at all.

I'm leaning making the turn and the bike just kept going down. I don't think there was anything slippery on the ground. Though it was dark and I can't be certain.

I've probably been through there 100s of times, on tires from many manufacturers (mostly sport touring tires, and mostly cold), and no issues. I've had tires before that didn't warm up well for me, and they might be too prone to slip, but didn't just let go like that. I hadn't been down on the street for 145k miles, and I've never low sided from excessive throttle or lean angle for conditions before.

It seems to me that my throttle and lean angle exceeded available grip, but I don't think I was asking that much of the tire. Maybe it was too much for virgin tire surface, or cold virgin tire? But the way the tread gouged makes me want to install a different tire.



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Old 02-24-2019, 05:30 PM   #2
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That looks like you ran over something.
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Old 02-24-2019, 06:02 PM   #3
davidji
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That looks like you ran over something.
That could explain why the scratches and scrapes in the tread aren't all in the same direction.
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Old 02-24-2019, 06:56 PM   #4
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Originally Posted by davidji View Post
Situation: making a left turn from a stop sign. Tire pressure measured at 40.8PSI. Ambient temperature 49-50F, and I'd ridden 1/2 mile before the crash. I had a total of about 70 miles on the tire from new. It had been over near the other edge, but not very far on the left at all.
I don't buy the "cold-virgin tire caused the low-side" theory, ever. People ride in cold rain/mud/snow without low-siding. It's always hard to guess what happened unless the rider provided a very nuanced description on the throttle/steering actions, but I've got some general questions:

What is the mystery tire?

Why's the tire pressure at 40.8 psi? What's the total load (rider plus luggage)?

With 70 miles on the tire, why's it been over near the edge on the right, but not very far on the left? Trying to figure out your riding habit/situation.

What do you normally do when you feel the rear sliding in a turn?

Last edited by Gary856; 02-24-2019 at 07:02 PM..
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Old 02-24-2019, 10:09 PM   #5
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Looks like a Continental Conti Motion tire, but I could be wrong. They're cheap tires, but that doesn't mean they're bad. I've gotten them leaned over to the edge of the tire tread on a liter bike, so this wasn't the fault of the tire.

Best bet is you hit a slippery... something. Oil, manhole cover, something.
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Old 02-25-2019, 07:07 AM   #6
davidji
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The deep gouges in the tread suggests to me that when the tire tried to hook up, the tread shredded instead.

I see 3 possibilities:
A) The shear strength of the tread is inadequate when cold
B) The shear strength of the tread is inadequate period. Maybe a defective tire.
C) As aware suggested, I ran over something.


B, and possibly A would have me wanting to replace this tire with one that doesn't suck. It's certainly possibly someone had dropped objects with sharp edges there.

It's not a Conti Motion.
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Old 02-25-2019, 07:14 AM   #7
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I run Shinko 705 (MFG recommended tire pressure 42lb) on my 2014 GS and the rear cost a little over $100 and the only time I feel any tire give is before they warm up or I run over something. Otherwise never an issue and I push the pretty hard and getting about 4K from a rear. Modern tire technology is pretty incredible.

Last edited by bmwbob51; 02-25-2019 at 07:15 AM..
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Old 02-25-2019, 07:31 AM   #8
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Unless you want it to brain-fuck you every ride, the details don't matter much; once you don't believe in a tire- ditch it for a new one.
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Old 02-25-2019, 07:32 AM   #9
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I run Shinko 705
I currently have those as well. I've run many tires, with mostly good results. This one may be an exception.

The fact that most modern tires work pretty well doesn't address the issue shown in the photos.
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Old 02-25-2019, 07:32 AM   #10
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Those marks aren't from sliding. You ran over something fairly sharp.

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Old 02-25-2019, 07:40 AM   #11
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Do you have an eye prescription? I do, and when I don’t wear corrective lenses or glasses I can easily miss something small that would cause this. I would question my eyes before the tire from the information provided.

Piece of road debris or soda can? I would go back and scrutinize the location of the low side for clues.

You said you have ridden there hundreds of times, which means you may well have been on auto pilot and not checking your line for debris.

You said it was at a stop sign, which is another popular location for debris.

Impressive amount of street mileage without incident, hoping you get another 150k without another! This makes me think your throttle control was fine.

$100 says it was debris
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Old 02-25-2019, 09:25 AM   #12
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Originally Posted by Gary856 View Post
I don't buy the "cold-virgin tire caused the low-side" theory, ever. People ride in cold rain/mud/snow without low-siding. It's always hard to guess what happened unless the rider provided a very nuanced description on the throttle/steering actions, but I've got some general questions:

What is the mystery tire?

Why's the tire pressure at 40.8 psi? What's the total load (rider plus luggage)?

With 70 miles on the tire, why's it been over near the edge on the right, but not very far on the left? Trying to figure out your riding habit/situation.

What do you normally do when you feel the rear sliding in a turn?
All good questions here...
Could the tire be a bit over inflated for the cold weather, If you were riding solo ?

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Old 02-25-2019, 09:40 AM   #13
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First, David, are you OK? Uninjured?

If I had experienced this, I would first be considering autopilot at an intersection I frequent often. I fight this laziness, but the problem is that it is sneaky.

To my eye, the scrapes do look like you rolled over something, lost traction, and there wasn't enough grip left in the tire/surface/acceleration equation to regain traction. I would give this even more credence if you were goosing it a little on your way out from the stop sign.

I agree with NorCalBusa to the extent of saying: If it is going to be a niggling problem in your head when you ride, get another tire. There are too many things needing your attention, and fretting over your tire is too much to ask.

Last edited by MapleRoad; 02-25-2019 at 09:42 AM..
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Old 02-26-2019, 04:00 PM   #14
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Agree with the others that those tears don't look like a normal loss of grip - those like there was something in the road that you likely ran over. What it was is anyone's guess since I'm under the impression you didn't go inspect the spot after the fact.

A tire that is losing grip from being cold doesn't look like that, and those tears are odd even for a crappy tire.
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Old 02-26-2019, 04:12 PM   #15
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I have to vote for both sides here.
No, I don't believe the tire was the cause but I imagine your loss of faith in it will remain in your head.
I'd be inclined to replace the tire, even though there's most likely nothing wrong with it.
Peace of mind has value too...especially in the corners.
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