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Discussion Starter · #1 ·
So today I rode my 09 from San Angelo, TX to Phoenix, AZ.

This is a pretty long ride through three states, almost all of which is on I-10. The first 300 miles were in the rain but after that dry til Tucson. Now the rainy bits were fine, but it wasn't until I had been riding in the dry for a while that I noticed a fairly big problem. My rear tire was starting to booger up in the center and I couldn't figure out why. I wasnt riding hard and the front tire was doing just fine and just squaring up a little like I expected, but the rear was really being chewed up down the center.

The tire had plenty of rubber left and I had a ****ing ton of miles to cover still. I finally stopped for a rest in Benson AZ and was sitting next to the bike when I noticed just how close the catalytic converter is to the rear tire, about a thumbs width. I always thought the rear tire got a bit greasy feeling after a while of riding, but the long term, consistent high speed with the proximity of the CC creates an extremely hot patch down the center of the tire that will cook it right out from under you.

I was lucky enough to see it happen when I got to Tucson and the rain... I stopped for gas, checked the tire and it was perfectly fine, if squared off pretty bad. After Tucson I stopped again just outside of Phoenix after about 80 miles in the dry... The boogers were back and the tire was pretty hot.
Ck
What would be a feasible fix for this, other than a new exhaust that I can't afford right now? Heat shield maybe? Would this possibly be a warranty thing?
 

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First post......welcome to the forum...and you might as well know now. Drop the "F" words in your postings. I have no idea about the tire issue but hopefully someone will be along shortly to help out with suggestions.
 

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My dunflop lasted 2279 miles , the angle is doing wayyy better so if yours is a dunflop , use it up change it out ride on
 

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4k miles on my battle axe and still some life left.
 

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3700 on the dunflop sportmax, but I am in Indiana and the pavement doesnt get that hot over here.
 

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Discussion Starter · #7 ·
Sounds like a combination of load and tire pressure. What is your weight in gear? Luggage? Tire pressure?
Well I thought that was a possibility but I'm just going with one kriega us30 at about 15 lbs and tire pressure when I started was 36psi. Not anything extreme to cause such extreme results.

This isn't an issue for short jaunts and whatnot. It's a combination of consistent high speed evenly heating up the center section of the tire. As an addendum, last night before Phoenix got nailed with storms, I was putting around town a bit and the tire boogers went away... Stop and go, relatively low speeds for shorter distances, the tire is able to cope with it/dissipate the heat quick enough.
 

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Well I thought that was a possibility but I'm just going with one kriega us30 at about 15 lbs and tire pressure when I started was 36psi. Not anything extreme to cause such extreme results.

This isn't an issue for short jaunts and whatnot. It's a combination of consistent high speed evenly heating up the center section of the tire. As an addendum, last night before Phoenix got nailed with storms, I was putting around town a bit and the tire boogers went away... Stop and go, relatively low speeds for shorter distances, the tire is able to cope with it/dissipate the heat quick enough.
Try running 40-42 psi on the rear for those highway stints. You're also running on some very hot roads down there.
 

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it's certainly not an issue in these cooler, damper climes. I can't imagine that the proximity of the exhaust is causing the problem.
 

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The part of the exhaust near the tire is a second chamber after the catalytic converter - so it isn't hotter than a normal exhaust. And the amount of clearance I have is more than plenty because of the amount of air that comes through there. Did you take a link out of the chain, go to a larger rear sprocket, or make any other mods? Unless the tire is a lot closer than mine is I would assume it's just due to a lot of hard riding, braking and accelerating.
 

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Discussion Starter · #12 ·
The part of the exhaust near the tire is a second chamber after the catalytic converter - so it isn't hotter than a normal exhaust. And the amount of clearance I have is more than plenty because of the amount of air that comes through there. Did you take a link out of the chain, go to a larger rear sprocket, or make any other mods? Unless the tire is a lot closer than mine is I would assume it's just due to a lot of hard riding, braking and accelerating.
I haven't done anything to the bike, but I wonder what is the normal clearance. I have less than an inch between the exhaust and the tire.

Like I said, with my thumb between them I'm touching both the tire and the catalytic converter. With the chain that's on there in suggested specification I assumed that everything was where it's supposed to be. I'm gonna get a new tire and see about backing the tire up a bit. Maybe with a new chain. Wl
 

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I run 36 in the rear unless I am on the highway for extended periods, then I run 40. I rode to Texas and back to Tennessee doing 80-85 the whole way on PR4's without any balling or excessive wear. Now my CBR954RR with sticky rubber always did it on our trecks to the road races. The rear would last 3,000 miles if I did any highway runs, no matter what the pressure.
 

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I haven't done anything to the bike, but I wonder what is the normal clearance. I have less than an inch between the exhaust and the tire.

Like I said, with my thumb between them I'm touching both the tire and the catalytic converter. With the chain that's on there in suggested specification I assumed that everything was where it's supposed to be. I'm gonna get a new tire and see about backing the tire up a bit. Maybe with a new chain. Wl
The heat from the exhaust didn't cause your tire to wear. The tear heated up from prolonged interstate riding with lower than specified tire pressure. Road surface condition can also exacerbate the situation.
 

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+1 on running more pressure in the rear tire. It's easy to forget that it's the air inside that holds us up, not the tire. ;-)
While your inflation pressure wasn't particularly low, I'm with the others that this was a combination of that, road surface condition and heat from the road - not the location of the catalyst.
One thing I didn't see was mention of was rear wheel alignment. It'd have to be off quite a bit and then would be noticeable via handling ills. Then again, a little off combined with everything else would not make for a happy tire.
 
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My battleaxes were done at 3000 miles (5000 km) I replaced at 6000km At 2000 miles the wear was noticeable (36 psi). The michelin pilot road 4 I have now has 3000 miles still looks great so I'm putting one on the front now (7500 miles/11,000 km)
The pilot 4 really feels planted on all surfaces
 
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