Dunlop front tire cupping?

[texas-ss-tornado]

Weird problem, I just picked up a 91 that needed fork seals. I had them replaced, but the bike still handles like crap, it wants to pull back and forth. In other words, if you turn left, it wants to keep going left, you really have to fight it to bring it back to straight. Seems going left is worse than right, but it's NOT a good feeling! I've had this same feeling on other bikes that needed steering head bearings, but then, I took a good look at the front tire and it's TOAST! It's cupped REALLY badly, I don't think I've seen a Dunlop cupped like this before! What could cause this, and is this most likely my issue??? I've already got a new tire ordered and on the way, just thought I would run this by the experts.

 

[Itgoes]

Every Vmax I've ever had (4) cupped the front tire including my Gen 2. It's just evidence the rider was very aggressive in turns on a heavy bike.

If the steering head bearings are not shot or too tight, just replace the front tire and you'll probably be all fixed.

 

[PATMAX]

I've got two Dunlops that are cupped before their time. Two different Maxes by the way, one late model fork with Progressive springs and the other stock early model forks. I drive them til I can't stand it anymore and gone Metzler and Avon. Shinkos are next on the list.

 

[Redbone]

I had a Shinko that cupped badly in about 4000 miles, a grippy tire but I never liked how it handled/ felt. I had just switched from stock 2 piston (HH pads) to 6 piston (HH pad) and was loving the extra braking power so I was all the time testing it's grip with the added braking prowess. The bridgestone I had on it before had seemingly wore out "normally" and the Metzler ME 880 was wearing normally before I put on the radial Shinko Verge's this summer. I'm thinking that you have a bad example of Dunlop workmanship.:confused2:

 

[Itgoes]

I had a Shinko that cupped badly in about 4000 miles, a grippy tire but I never liked how it handled/ felt. I had just switched from stock 2 piston (HH pads) to 6 piston (HH pad) and was loving the extra braking power so I was all the time testing it's grip with the added braking prowess. The bridgestone I had on it before had seemingly wore out "normally" and the Metzler ME 880 was wearing normally before I put on the radial Shinko Verge's this summer. I'm thinking that you have a bad example of Dunlop workmanship.:confused2:

If you turn hard and brake hard any tire will do it.....dosen't matter what brand it is. A softer compound will obviously do it faster (Shinkos are pretty soft). I've had Dunlops, Avons, Bridgestones, Continentals - doesn't matter....the front ones always end up looking the same.

I ride mostly in the mountains so it's nothing but turns. If you ride where it's mostly flat and straight you'll probably never have the problem.

 

[texas-ss-tornado]

Well, the new tire didn't fix it, nor did the new fork seals. Looks like I'll be needing steering head bearings! CRAP!!!!!!

 

[PATMAX]

Does that mean new races too or just the upper and lower bearings?

 

[texas-ss-tornado]

Does that mean new races too or just the upper and lower bearings?

I won't know until I get it apart, will probably be a week or two, most of my tools and bike lift are still a hour south of me at my father-in-laws house!

 

[sdt354]

I'm disappointed that my Metzler z6 is wearing bad with lots of thread left. I did do the steering head bearings with some miles already on them though. The bad wear may have started before it was noticable. I'm not going to give up on them and will replace the front with a new z6. They are reasonable to buy right now and grip well wet or dry.

 

[Rollie]

If you turn hard and brake hard any tire will do it.....dosen't matter what brand it is. A softer compound will obviously do it faster (Shinkos are pretty soft). I've had Dunlops, Avons, Bridgestones, Continentals - doesn't matter....the front ones always end up looking the same.

I ride mostly in the mountains so it's nothing but turns. If you ride where it's mostly flat and straight you'll probably never have the problem.

+ 1 Google motorcycle tire cupping and you'll get a lot of various reasons for cupping. Turning & braking hard, softer compounds & out of balance or improper inflation of the tire , steering head bearings, wheel dinged , tire and / or frame out of alignment , fork springs / oil shot , etc.