Dunlop E3 strange wear????

[CMIKE]

We have a big trip planned for the 1st week of July so I am a little concerned about the rear E3. Got to looking at it real close and it is scalloped on the sides. UMMM...what caused that? This is a rear tire and I run 40 PSI in the tire and check it regularly. I ride 2 up about 1/2 time and still check the pressure regularly. As you can see I do not ride the twisties much cause there just not that many roads here that have twisties...Mostly straight road with slight curves compared to the smokies. I got 13700 miles on it so far...still got about 4-5/32 tread depth but it is kinda noisy when you get it off center. I am well pleased with the performance of this tire and feel I have got my money's worth, although i could probably get another 3-5000 miles out of it...why take the chance. You know what they say if you are thinking about changing a tire...you should go ahead and do it...if you are going on a road trip.

 

See attachments for photos...43 and 44 is the same tire looking at different directions...the other one is side view you can see the slight raising at the tread grooves.

 

I am gonna change it just in to be safe for the trip, since we do not know how far we will go and really have not decided how long we will be gone. The wife and I are off from work for 3 weeks and we plan to ride till we get tired then turn around and head back home.

The rear wheel is at the closest dealer swapping the tire now.

 

Just wondering...What caused this??? What do you think?

[V7Goose]

That is definitely very strange wear - feathering is very common on that tire, but that is not what I see in your pictures. I have not seen it exactly like that, so I can only speculate on typical problems that can cause irregular wear.

 

Loose shock mounts or improper dampening from the rear shock can cause very strange wear problems, as can worn swing arm bearings. And balance, of course, can so lots of strange things.

 

But the one I suspect is the easiest to check if you have not yet dismounted the tire from the rim -is it beaded up perfectly concentric with the rim? Look very closely at the little rib on the tire just next to the rim - the E3 has two of them, one about 1/4" out, and one that is just barely visible right next to the rim. Look all the way around and make sure this inside rib is exactly equal in every spot on both sides. If it disappears under the edge of the rim at any point, you have found the cause.

Goose

[CMIKE]

That is definitely very strange wear - feathering is very common on that tire, but that is not what I see in your pictures. I have not seen it exactly like that, so I can only speculate on typical problems that can cause irregular wear.

 

Loose shock mounts or improper dampening from the rear shock can cause very strange wear problems, as can worn swing arm bearings. And balance, of course, can so lots of strange things.

 

But the one I suspect is the easiest to check if you have not yet dismounted the tire from the rim -is it beaded up perfectly concentric with the rim? Look very closely at the little rib on the tire just next to the rim - the E3 has two of them, one about 1/4" out, and one that is just barely visible right next to the rim. Look all the way around and make sure this inside rib is exactly equal in every spot on both sides. If it disappears under the edge of the rim at any point, you have found the cause.

Goose

 

I appreciate it...

I guess if it was the shock...or balance...why would it do it only on the sides? Middle smooth as can be...wouldn't I feel the out of balance condition? The tire appeared to run smooth...only indication was the noise when you got it off center.

Ummm...bike has only 18K miles...I know it is possible but I would not think I have worn swing arm bearings so soon...huh?

Loose shock mounts...I do notice when I have it on a lift...then let it to the ground...when I first put my weight on the bike, I feel it drop about 1/4 inch. Only if I have had it off the ground. No oil on or around the shock...

[CMIKE]

Wait Goose... what do you see besides feathering?

[buddy]

Mike

I ride with a guy once in a while who rides off center on his motorcycle to either side and doesn't even know it until we say something anyway his rear tire looks like this feathering on the sides and the center is smooth.....

its kinda funny following him some times because it looks like he might fall off.....

Buddy

[V7Goose]

Wait Goose... what do you see besides feathering?

Well sir, it is real hard to tell when just looking at couple of pictures, but I thought I could see a strange off-center wear pattern, just in specific places on the tire. In particular, look st the third picture, right side, just this side of center before the main roll-off of the side. The picture looks like it is a bit worn down there, with a bigger bump before the roll-off. And the other pictures seemed to show hints of similar irregularities.

 

But it wouldn't surprise me at all if all that is just a distortion in the 2-D picture of a 3-D object.

 

If your actual examination of the tire shows that it has a normal rounded profile equally all the way around, and you are just seeing feathering on one side of the grooves, then I'd say there is nothing to worry about. In my experience with several of the E3s, this is a typical fault of this tire. I do not know what causes it, but I do not get the same thing from Avon Venoms on the same bike.

Goose

[CMIKE]

Loose shock mounts or improper dampening from the rear shock can cause very strange wear problems, as can worn swing arm bearings. And balance, of course, can so lots of strange things.

 

I took a good look at the play on the swing arm and shock.

I have a magnetic base Starlet dial indicator and I found +/-.20 in (total .40in) side to side motion...and .60in up and down slack. The up and down slack is at the top of the shock...is there a bearing where the top shock bolt goes through? It seems the bolt is smaller than the hole in the shock and it is moving.

The side to side may be some deflection from the steel swing arm since I am measuring it near where the axle bolt goes through just behind that last weld.

The book says 0 in/mm play in either direction...

Re-torgued all bolts on the shock and lnks…took another reading

Now it is at +/- .05 side to side and .20 up/down slack. Lot better but still not as the book says. 0 in/mm... what do you all think?

 

 

But the one I suspect is the easiest to check if you have not yet dismounted the tire from the rim -is it beaded up perfectly concentric with the rim? Look very closely at the little rib on the tire just next to the rim - the E3 has two of them, one about 1/4" out, and one that is just barely visible right next to the rim. Look all the way around and make sure this inside rib is exactly equal in every spot on both sides. If it disappears under the edge of the rim at any point, you have found the cause.

Goose

 

I looked at the two lines around the bead you talked about above...you can clearly see where the wheel was on the tire...looks like it was seated good on the rim.

I looked at the tire really good...seems even wear on both sides of the tire...no noticable difference between left and right sides and all the feathering seems to be pretty close to the same all around the tire...looks like the photo may have been misleading.

 

I appreciate the advice from all of you.

[Squeeze]

...

Now it is at +/- .05 side to side and .20 up/down slack. Lot better but still not as the book says. 0 in/mm... what do you all think?

 

...

 

That's too much play, especially on the up/down Motion. There should be next to no Play on the Side to Side Play, but each and every Tenth unsprung and undampened Travel in the up/down Direction is very bad. Looks like you found the Culprit with your Tire.

Edited July 2, 2010 by Squeeze
typos

[CMIKE]

Ummm...sounds like I may need to get some warranty work...or maybe work a deal so they at least supply the parts.

 

Thanks guys for all your input.

[BigBoyinMS]

Hey Mike,

 

I just now saw this. Something you may want to check. Maybe you remember my bald headed Wing riding buddy, Bob. He has E3's on his '06 Wing and I noticed that his tires had a similar wear pattern a few months ago. They actually looked like they had a flat center and each side was beveled and scalloped. Anyway, I asked him what pressure he ran. We checked his pressure with my new digital gauge and then his gauge. His showed about 8lbs high so he was running 8lbs low the whole time. (FYI, I verified mine with a calibrated gauge at work.)

Do you think you may have the same issue? Just a thought.

[CMIKE]

Hey Mike,

 

I just now saw this. Something you may want to check. Maybe you remember my bald headed Wing riding buddy, Bob. He has E3's on his '06 Wing and I noticed that his tires had a similar wear pattern a few months ago. They actually looked like they had a flat center and each side was beveled and scalloped. Anyway, I asked him what pressure he ran. We checked his pressure with my new digital gauge and then his gauge. His showed about 8lbs high so he was running 8lbs low the whole time. (FYI, I verified mine with a calibrated gauge at work.)

Do you think you may have the same issue? Just a thought.

 

Hey what kind of trouble you been stirring up lately...I know you have been up to no good...

 

I have a couple of digital gauges here at the house...they are pretty close last time I checked them...I use the same one on my bike. Maybe I need to check these gauges again. I try real hard to keep 40 PSI in the rear. I am kinda ANAL about tire pressure.

Thanks for the input I may got get them all out now...

[CMIKE]

Test on 3 tire gauges...filled an air tank to check the pressure...I think some of this is the little bit of air you loose each time you check the pressure. 39.6 first one 38.9 2nd one (-.7) and 38.6 third one (-.3)...

I suspect it is not likely they are all off by the same amount but it is possible...they are all the same brand.

[ctraylor]

I may be wrong but I think that that tire holds 50 psi. That is what is on the sidewall of my E-3 on my first gen. I run what is on the tire and haven't had any problems.

[V7Goose]

I may be wrong but I think that that tire holds 50 psi. That is what is on the sidewall of my E-3 on my first gen. I run what is on the tire and haven't had any problems.

This is not correct for the 2ng Gen. The 150/90-15 rear E3 has a maximum pressure of 40 lbs. In my experience, it must be kept at 40 for best handling.

 

As I said in several earlier posts in this thread, feathering on the sides seems to be a specific fault of this tire, as I have seen it on four of them so far (on three different RSVs). On my own RSV, no other rear tire has done this, but two E3s have. There is always a possibility that something has worn more recently that is causing this, but I haven't found any problem so far.

Goose