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Naustin
| Posted on Thursday, September 20, 2007 - 08:23 pm: |
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What caused this goofy tread wear on my front tire. I'm running the new BT021 and I realize they are dual compound, but I have not been riding a lot of twisties on this set of tires. The rear is squared off and ~1mm from the wear bars in 4,000 miles and shows very little wear on the shoulders. The front is practically the opposite... I run 40-42psi in the rear, and 38-40 in the front. 75% of the 4,000 miles on this set of tires was 2up. When ever I found a 45mph sweeper around some farmers feild, I'd enter at 70 and exit about 80, but like I said, the majority of this set of tires was bituminous chip seal, straight, flat secondary highway. I've got a 800-1000 mile weekend coming up and after that I'm sure the rear will be toast. I hadn't really looked at the front until last night and now I'm worried it might not be so safe with this goofy wear... Nick
(Message edited by naustin on September 20, 2007) |
Ft_bstrd
| Posted on Thursday, September 20, 2007 - 08:28 pm: |
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Your front pressures seem a little high. I don't know. That's weird. |
Naustin
| Posted on Thursday, September 20, 2007 - 08:34 pm: |
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Yeah, I'm running it on the high side because I was doing so many 2up miles. Maybe that's all it is. I mean, if the pressure is too high, the harder center compound might never heat up enough to wear normally... Any other thoughts? |
Mikef5000
| Posted on Thursday, September 20, 2007 - 08:34 pm: |
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I have the same tires, but mine wore evenly. Squared off front and rear about the same. (Not like yours) That's very strange. I ran about the same pressure as you through the life of the tire. |
Naustin
| Posted on Thursday, September 20, 2007 - 08:36 pm: |
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Yeah, that's what I thought, I remember you were running similar pressure.... The drawing is exaggerated, but the center is at least .5-.75mm taller and the transition is really easy to feel. (Message edited by naustin on September 20, 2007) |
Wile_ecoyote
| Posted on Thursday, September 20, 2007 - 08:39 pm: |
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Maybe a broken belt. Too much psi, I'd run no more than 36 in the front two up or not. COLD PSI as the tire will grow when hot. Try a different gauge or compare between a few. I have had a few show 1-2 lbs low and a few show 1-2lbs high. Thats a big deal when you are already on the high side. |
Skeeter_xb
| Posted on Friday, September 21, 2007 - 02:28 pm: |
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I've seen the same thing on an R1100RT BMW. I think it had Metzelers on it. Weird |
Austinuu
| Posted on Friday, September 21, 2007 - 02:33 pm: |
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My Pirreli Diablo is doing the same thing. Running 36 psi up front. WEIRD! |
Bluzm2
| Posted on Friday, September 21, 2007 - 04:04 pm: |
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Nick, I run mine at about 35, I've had no weird wear like that! |
Just_ziptab
| Posted on Saturday, September 22, 2007 - 12:52 am: |
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Three things to consider. (1)The tire is defective with way too hard of a rubber compound in the center section or way too soft of a compound on the side sections.(2) The center of the tire has work hardened/oil hardened from running on the chip seal. The rock and oil binder in the chip seal is impregnating the tire........ microscopically with oil.......and in time, hardening it. Not sure how long this effect takes, whether it's days, weeks or months. (3) The chip seal is softening the side sections. Yes, oil does work both ways on rubber, depending on the chemistry. I have dual compound Pilot Roads on three Buells and all are wearing fine. All miles are on old, dried out asphalt roads or concrete. |
Naustin
| Posted on Saturday, September 22, 2007 - 01:39 pm: |
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I'm going to drop the pressure to 35 and see how it looks when I get back from my trip next week. It'll be about 1000 miles so if that helps, I should be able to see some improvement. |
Thespive
| Posted on Saturday, September 22, 2007 - 03:21 pm: |
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Car tires wear like that when they are underinflated because the center will fold up, but I have never seen anything like that on a bike. --Sean |
Jcbikes
| Posted on Saturday, September 22, 2007 - 07:41 pm: |
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My front tire (continental road attack) is the same way. The front wore like that with good tread in the middle and the sides are now bald . Their rear wore normal and is down to the wear strips in the back. both tires need replacing now. 38 psi in front and 40 in rear. BUT...I have over 7,000 miles on them. Maybe riding nothing but curves here in the canyons of Colorado is why the dual compound wears faster on the sides. |
Naustin
| Posted on Saturday, September 22, 2007 - 09:43 pm: |
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Now, one last twist, I compared the stick type gauge I normally use to an expensive analog dial type gauge and, presuming the dial type gauge is accurate, the stick type gauge is wildly off. The dial type reads the front at 34psi while the stick reads 38. The dial reads the rear at 38 while the stick reads it at 40. So, I have been actually running significantly lower pressure than I thought, more like 34/38 - front/rear, which further suggests that over-inflation is not the issue. This would also put me right in the middle of Buell's recommended pressures which are 32/36 solo, 36/38 loaded. here's another angle:
(Message edited by naustin on September 22, 2007) |
Naustin
| Posted on Saturday, September 22, 2007 - 09:48 pm: |
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Blurry, but you can still see the center bulge...
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Iamike
| Posted on Saturday, September 22, 2007 - 10:01 pm: |
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Nick, That's kind of what my rear D220 looked like when it was run at 35# for quite awhile. Honda recommends 42# on the ST. I got kind of spoiled with the PM wheels, I hardly ever have to add air. On the Honda I have to check it every couple of weeks. |
Naustin
| Posted on Saturday, September 22, 2007 - 10:40 pm: |
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I don't think mine leak either, my problem has apparently been the cheapo tire pressure guages I've been using. Either way though, whether the problem has been too little pressure, or too much, I think I'll have to try a different tire next time. I'm not real happy with the miles I got anyway. I've got 4,000 today and will have 5,000 after this trip and the rear will be shot for sure after that. Later, Nick |
Wile_ecoyote
| Posted on Sunday, September 23, 2007 - 11:09 am: |
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Well, that blows my theory. I guess you cant always be right.(not that I ever am) |
Just_ziptab
| Posted on Sunday, September 23, 2007 - 11:16 am: |
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Pressure rise:http://www.factorypro.com/tech/tire_pressure_risez .html |
Slaughter
| Posted on Sunday, September 23, 2007 - 11:29 am: |
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Did you send a note in to the Bridgestone folks? Most tire sellers don't know squat about tires - they just sell them. If you buy your tires from people with track experience, they can tell you LOADS of information from how your tires are wearing - from how your pressures are set to your suspension settings. See if you can find who is selling Bridgestones to racers in your area and ask them - shoot them a note with the pics. I'm wondering if the dual compound isn't just giving you that weird shape because of the harder rubber in the center - but I am not a Bridgestones kinda guy. |
Slaughter
| Posted on Sunday, September 23, 2007 - 11:35 am: |
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I'd recommend shooting Little Big Racing a note. They're the Bridgestone dealer out here at Willow Springs and they race and ride all sorts of bikes. Jean Marc Arechiga and Britt Arechiga are really great folks. You might google up the local racing Bridgestone tires folks in your area to see if they can help. Believe it or not, even though it's not RACING you are doing, the problems seen in performance tires ARE often seen in racing and I'd bet you can get some help. I wouldn't throw the baby out with the bathwater - see what the Bridgestone people say when they see the pics. Also, ALL racing tire sellers WILL sell direct - you don't have to be a racer or be at the track (though if you DO go to the track with a set of wheels ready for tires, you'll save HUGE money!) |
Slaughter
| Posted on Sunday, September 23, 2007 - 11:39 am: |
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Think I may have found the Bridgestone retailer in your area who sells motorcycle tires at the following tracks: Autobahn, Blackhawk Farms, Brainerd, Gingerman, Heartland Park Topeka, Mid-America Motorplex, Motorsport Park Hastings, Road America, and TrackAddix events at Gateway and Hallett. http://www.Motorcycle-KartTires.com Again, I am NOT a Bridgestones guy (except for Sunny's vintage VF500 Interceptor's odd sized tires) - so I'm not getting any kickbacks here! Just bored and "googling." <edit> - the contact guy on their website is the tech contact for Bridgestone Firestone. You might try shooting him a note. grahambob@bfusa.com - otherwise go ahead and shoot Jean Marc and Britt (Little Big Racing) a note, tell them Slaughter put you up to it since you are thinking of changing to another brand. They might be able to help. (Message edited by slaughter on September 23, 2007) |
Wolf102
| Posted on Sunday, September 23, 2007 - 01:14 pm: |
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the front tire on my vrod is doing the same thing |
Dnchevyman
| Posted on Sunday, September 23, 2007 - 01:19 pm: |
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are you doing long interstate rides when its windy??? or a lot of windy riding period? cause mine wore like that too after i did a 3200 mile road trip that was 80% Interstates and windy a lot of the time so i was at a constant lean..... |
Xl1200r
| Posted on Monday, September 24, 2007 - 09:32 am: |
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Just as a note - my front tire looks like that as well and I'm not running a dual compound. I'm not terribly worried about it. |
Slaughter
| Posted on Monday, September 24, 2007 - 02:47 pm: |
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This would also put me right in the middle of Buell's recommended pressures which are 32/36 solo, 36/38 loaded. Naustin, Did Buell recommend those pressures for the Bridgestones? Realize pressure recommendations have to be for SPECIFIC TIRES - and NOT for the motorcycle... just making sure. |
Slaughter
| Posted on Monday, September 24, 2007 - 03:15 pm: |
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I just got this in from Jean-Marc Arechiga - Little Big Racing (I sent him the pics and your sketch):
quote:Steve, You know, that REALLY looks like those tires were run with pressure much too LOW. I'm not suggesting your friend is untruthful, but I'm thinking something is up with the gauge, or he didn't check it often, or they leak, or something. J-M
Seems you might be right about your suspicions about lower than normal pressures. How often do you check pressures? Good idea to do a pressure check every morning before you ride. |
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