Anybody seen Shark Fin tire pattern before?

[RavenGS]

Running Avon Distanzias on my 04 1150GS, along with the Dinobeads. About 5000 miles on them and the front is wearing out on the, well, backside of the tread block. The leading edge is forming hard areas about the size of a nickel. Very strange, never seen a tire wear like this. Usually run around 36 psi in it.

Any thoughts? (Don't think I'm buying these again):nono

RavenGS
R1150GS
Lino Lakes, MN

[MotorradMike]

I get this too and am distressed about it as well. The first time I showed the dealer who is also an accomplished racer and he said(right away) inadequate pressure. Well, I am SUPER paranoid about pressure because my old bike lost 1PSI per day but I took his advice and kept higher pressure in the tires than the book said and guess what? Same problem. I now believe this is normal! The tread blocks squirm under riding forces and wear unevenly and result in scalloped tread blocks.

My latest worry is that maybe these scalloped tires don't have the same road friction as new ones...

I know I'm not answering your question, I just hear you and am hoping someone else knows what's up.

Mike

[RavenGS]

Thanks Mike, but to clarify; are you running the Avon Distanzia?

[MotorradMike]

No, I have Battleaxe Bt020 tires.

Mike

[bikerfish1100]

those tires are showing what is commonly called "scalloping" or "cupping". do a forum search on either term, you'll get a ton of results. causes are varied, but most common does seem to be low pressure. However, some brands/models do it more than others (BStones 020s have shown a strong proclivity for it in my experience), hard front braking can exacerbate the condition, tho many tires seem immune to it. Tires with more pronounced blocks of tread (from water sipes going across the tire rather than along the length of it) are more prone to show it. Also, some believe that it is also aggravated by our Telelever front ends.
I've only gotten it on BStones- never on DiabloStradas or RoadAttacks- my 2 current fave tires (tho i am hot to try the new PRoad 2s).

[BuddingGeezer]

Something to ponder. http://www.rattlebars.com/valkfaq/tirewear/

Ralph Sims

[motoman1150rt]

I had to replace the front tire on my 03 RT after only 3500 miles. This is the second time when running a set of Battlax that the front has given out before the rear. I quess I ride hard but I am done w/ Battlax front tires. I am getting ready to order a set of Shimkos and give them a try. I go thru Approx. 3 sets of tires per year. Me and a friend of mine mount our own tires and he just mounted a set on his 04 RT and seems to be getting good service from them. Any opinions ????

[bikerfish1100]

Shimko? Is that like a Cheng-Shin knock-off?

[RavenGS]

The best I've found for my GS was the Pirelli Scorpions, which I liked a great deal and gave me around 9500 miles without any of the scalloping I have on this Avon. But sigh, they seemed to have quit making them in the GS sizes. :cry

[DarkCloud]

You got big problems. What you have is a classic "tractor tire" chop pattern caused by hard braking on the front brake. If you were to take a 1000 mile ride on interstate, you could see natural tire wear correcting this wear pattern. The big problem is that you have servo brakes which should be applying the rear brake along with the front brake. This woudn't allow the para/tele lever suspension to suck the front wheel back, loading the weight on the front tire, and causing it wear the tire like it is doing.

[RavenGS]

Dark Cloud,

Not sure about your assessment of my problem although thanks for the info. I did take a 1500 mile interstate on this very tire just a couple of months back and this was present and has just been getting worse. As for the rear brake; it's working because I rarely use the rear brake pedal but the pads have wore out before.

I agree that the braking is liking the culprit. But I believe it only in that certain tires, such as this Avon, have the problem this bad. As I stated earlier those Pirellis had much more mileage and demonstrated none of this issue at all.

Thanks to everyone for the info.

[JimVonBaden1]

You got big problems. What you have is a classic "tractor tire" chop pattern caused by hard braking on the front brake. If you were to take a 1000 mile ride on interstate, you could see natural tire wear correcting this wear pattern. The big problem is that you have servo brakes which should be applying the rear brake along with the front brake. This woudn't allow the para/tele lever suspension to suck the front wheel back, loading the weight on the front tire, and causing it wear the tire like it is doing.

That whole assertion, IMHO, is just innacurate!

I have servo brakes, as do many I know with the R1200GS, and this is most definitely not anything to do with them. It is more about hard braking and underinflation. I get as much as 16K miles on my front tire with only mild cupping towards the end of the tire life.

I never use the rear brake for stopping. The R1200 servo-ABS is a partially linked system with the front activating the rear at the same time. You use the rear anytime you use the front.

Jim :brow

PS I am on my 7th set of Avon Distanzias with nothing like this issue!

[Andy VH]

Tire cupping/scalloping is related to tire pressure and is made worse when the shocks loose their dampening capability, which on BMWs is about after 15,000 miles from new. The constant, high frequency bounce/flutter of a suspension system that has lost its dampening ability causes a fast, high cycle compression/release on the tread blocks that causes advanced tire wear.

The last set of tires on my 94 RS cupped significantly. I recently mounted up some Continental Road Attacks at the same time I installed new Wilbers shocks. WHAT A PHENOMINAL RIDE DIFFERENCE!! I am tracking the tire pressure and wear patterns closely to see if I can any cupping. I expect that with the new shocks I will get much better tire wear. I don't buy the "excessive hard braking" causes tire cupping, because I really, really doubt there are many riders who really use their brakes that much and that effectively. I have taught the MSF ERC for many years, and I am always surprised by the low braking capability of supposedly "experienced riders". I for one do a lot of braking, and downshifting, both which transfer loading to the front tire, and I don't feel it significantly affects cupping.

Bikerfish1100, you live in Colorado and ride your R1100S on the mountain roads a lot. So if anyone would be doing a lot of braking it would be you. I know your bike has good shocks. Do you have, or have you experienced any real tire cupping issues?


I for one would never run Cheng Shin or Shinko tires on any of my bikes, especially on my BMWs. I teach the MSF program, and last year I taught on a wet day, and had five bikes go down, and every one of them was on Shinko tires. Granted, this was a bunch of fairly new riders, but in 16 years of teaching the MSF I have never had a day like that. And I have taught the program in the rain many times. Crap tires in my opinion. You only have two palm sized patches of rubber to ride on.

Don't mess with your life for a pair of cheap crappy tires!

[bikerfish1100]

Bikerfish1100, you live in Colorado and ride your R1100S on the mountain roads a lot. So if anyone would be doing a lot of braking it would be you. I know your bike has good shocks. Do you have, or have you experienced any real tire cupping issues?




i'm a fairly fast/aggressive rider, and when i do use my brakes i tend to go with the fronts for speed adjustment, and do so strongly (honestly, i ride "the pace", so tend to do the vast majority of speed adjustments with my throttle. if i'm on the brakes, i am ON the brakes!).
I've gotten severe cupping on BStone BT020s (was glad to wear those out!) on my K11RS (hmm, no telelever, and it still cupped). I've gotten very mild cupping on PRoads as well, but only showed up at the very end of the tire's life span. My preferred tires have been RoadAttacks and DiabloStradas. Both of those tires have no to minimal cross cuts in the tread (no real blocks to speak of), and neither cupped at all. I'm convinced that cupping is primarily a function of tread design (more pronounced lateral sipes across the center of the tire = more cupping), which can be exacerbated by low tire pressure.
Shock up front is a Wilbers, and it gets renewed/rebuilt every 30K or so.