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Discussion Starter #1
Before you get onto the "YOU NEED NEW TIRES!!!!" thing...I already ordered some, just waiting for them to arrive.

Anyhow, why are they like that? They're scalloped, but particularly, it's worn smooth OFF CENTER.....

When you look at the overhead shot, you can see how they're scalloped and there's a block of tread actually protruding to a point off center, then the worn flat spot. When you run your hand over it, it doesn't feel smooth round all the way around like it's worn evenly, rather, it's flat, hump, flat hump, as if I had flatspots in the tire.

When I lean left during a turn, I feel it "fall" into the worn spot, but how the hell is that worn like that if I can feel myself fall into it? You would think if it were wearing off center like that, I'de have a cambered wheel....or is it truly crooked???

Is it a wheel balance issue? I looked, and I have no balancing weights on my front tire

The bike doesn't veer to the left, and it stops in a straight line, and oddly enough, there's no wierd vibration from it...wtf causes this, so I know how to prevent it on my arriving tires? And before you ask...that's just under 8K miles on that Pilot Sport....

My rear however, is wearing completely normal.
 

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I've seen this on soft tires used for street riding. I believe it's a combination of road crown loading the tread left of center and the habit of pushing the front a bit when making a left turn from a stop. We turn left in a larger radius than on a right turn (from an intersection) and tend to get on the gas a little harder.
 

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Discussion Starter #3
but why would it ALSO cup like that??? Not to also mention, it's not smooth, there's flatspots on those worn out places, like I sanded it down. It's funky...
 

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check the suspension settings - specifically the compression damping (the adjuster on the bottom of the fork leg - at the axle). see if that one is out of wack.

btw, the brutale manual should have some suggested settings for general road riding. i'd start with those then tweak it as you like

alex
 

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Discussion Starter #5
I got it dialed in for my weight when bought, then just left it alone...hmmm....gonna redo them tonight then, see how it all feels in the morning....
 

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Discussion Starter #6
Well, I just went out there and adjusted the suspension settings to the softest setting according to the manual. There was only soft standard and rigid.....it was previously on rigid...we'll see tomorrow on the ride to work, how I like riding a "plush" bike....
 

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I have seen tires wear in very odd ways as a result of low tire pressure or a good panic stop where they actually wore a flat spot from locking the tire up, but I have never seen anything like that.
 

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I think a good starting point would be to check your tyre pressure gauge accuracy, I am actually an Instrument technician by trade, and auto tyre pressure gauges are pretty poor on the accuracy front, it's not unusual to see 3 psi difference between them :jsm:
You probably need to spend (in the UK) around the £15-£20 to get a reasonable one, cheap digital one's are usually worse. Try and get one from the like of Demon Tweeks in the UK, or a Racers Hardware store in the USA, just to make the point, F1 type gauges cost wise are in the Hundreds of pounds :jsm:
 

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I agree with Greg. I have had the same tire wear on my BMW and it is a result of road crown, soft tire, and some underinflation. The cupping can result due to lower tire pressure. On my heavy BMW, I usually inflate the tire to 4 PSI over recommended pressure. Any way it is time for new tires.
 

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I'm sorry but the road crown argument just doesn't stand up - unless ofcourse you ride a bmw - next we will be discussing the 'pull to the right' and shaft-drive crown bearing failures.... lol! If 'road crown' was a real issue all bikes and all tires would exhibit the same characteristics but they don't...
How about starting by checking your alignment [front to rear wheel] and tire pressures move on to steering head bearing torque and tire balance. 8k on a pilot sport which is what 4 or 5 years old? is good milage - on my old 900ss I used to get 1800 miles out of a front! 2 front tires for each rear. What pressures are you running? Certainly suspension settings can influence tire wear significantly but cupping is usually alignment, pressure, balance, bearing tightness, axle alignment or simply a bad tire. BMW 1150rt's and newer goldwings, VFR 800's Ducati ST's and Triumph sprint's exhibit this tendancy with certain tires and not with others - I have seen Cupping like this in many instances on different bikes in different countries including Britain where the road crown falls the other way and the cupping is still on the left side.
Something else - when riding in a straight line see if you are using more pressure on one bar than the other - pushing the left bar a bit, like a tiny amount of constant countersteering to make the bike travel straight - then see what happens when you have measured adjusted and changed to a new tire, any difference?
 

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quacker998 said:
I'm sorry but the road crown argument just doesn't stand up - unless ofcourse you ride a bmw - next we will be discussing the 'pull to the right' and shaft-drive crown bearing failures.... lol! If 'road crown' was a real issue all bikes and all tires would exhibit the same characteristics but they don't...
How about starting by checking your alignment [front to rear wheel] and tire pressures move on to steering head bearing torque and tire balance. 8k on a pilot sport which is what 4 or 5 years old? is good milage - on my old 900ss I used to get 1800 miles out of a front! 2 front tires for each rear. What pressures are you running? Certainly suspension settings can influence tire wear significantly but cupping is usually alignment, pressure, balance, bearing tightness, axle alignment or simply a bad tire. BMW 1150rt's and newer goldwings, VFR 800's Ducati ST's and Triumph sprint's exhibit this tendancy with certain tires and not with others - I have seen Cupping like this in many instances on different bikes in different countries including Britain where the road crown falls the other way and the cupping is still on the left side.
Something else - when riding in a straight line see if you are using more pressure on one bar than the other - pushing the left bar a bit, like a tiny amount of constant countersteering to make the bike travel straight - then see what happens when you have measured adjusted and changed to a new tire, any difference?
i fully understand your point
but.....

ride 8K miles on MOST florida roads... in a straight line (the FLORIDA WAY :) ) and your tires will look EXACTLY like this... i promise
i guarantee that the crowns on our roads are MUCH higher than those in New York
because.....
1. rain runoff concerns
2. YES, you have rain in NY, but you also have snow and you CAN'T have a GIANT CROWN in NY roads 'cause folks will slip off into a ditch when the roads are icy



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mikef4uk said:
I think a good starting point would be to check your tyre pressure gauge accuracy, I am actually an Instrument technician by trade, and auto tyre pressure gauges are pretty poor on the accuracy front, it's not unusual to see 3 psi difference between them :jsm:
You probably need to spend (in the UK) around the £15-£20 to get a reasonable one, cheap digital one's are usually worse. Try and get one from the like of Demon Tweeks in the UK, or a Racers Hardware store in the USA, just to make the point, F1 type gauges cost wise are in the Hundreds of pounds :jsm:
Motorcycle Consumer News did a very extensive comparison of tire pressure gauges. The results defied conventional wisdom (i.e. $$$ = accuracy). According to their tests, a couple of "cheap" digital ones did rather well.

Specifically, a $9 digital pressure gauge from Radio Shack came out near the top (NOT the top), of the group. It's accuracy was +0.5/-1.5 psi, measured from 20 to 50 psi. I have one of these, and I tested it recently @ 30psi against a "reference" provided by a race tire vendor. The gauge showed 30.1psi. I checked it 2 times during the day. Same results.

The most accurate, other than the $500 Intercomp Digital was this Tire Gun but it requires an air compressor.

This particular model from Accutire (from Amazon.com) had 0.5 psi accuracy across the entire range! It was ranked 2nd in the group.

BTW, this comparison is in the November 2005 issue of Motorcycle Consumer News.
 

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Front tire cupping, again with soft compounds is not at all unusual in my experience. Hard braking puts a high load on the tire and the tread blocks around the sipes will deform and squirm. This scrubs some rubber away and over time results in a cupping pattern. I've had it happen to most of my sport bikes and race bikes that ran DOT tires (i.e. 600 Supersport and 750 Superstock).

The left side wear has already been explained by Greg.

By all means look at alignment, but don't lose any sleep over this wear pattern.
 

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Discussion Starter #16
Well IU changed my suspension to teh softest as I stated earlier and HOLY CRAP do I like it this way...it feels so much more planted on the bumps around here with it not being so stiff. It's still supple, but it's definitly not as "race" feeling...

I'm 99% sure it is the road crown..I kept a mental note about it, and yeah, the roads are SUPER crowned, especially on our highways...something I never really paid any attention to before. Can't wait to get new tires....with the new suspension settings, should be like day 1 all overagain....
 
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