Scalloped front tire question

My front tire has scalloping on the left side only from the center line. right side is Okay. Tire is a Dunlop and is near replacement time, pressure is 34PSI front 36PSI Rear. The bike is an XJ1100J Maxim '82. I use both front and rear breaking, rear is proportional stock.
Any explanation is appreciated. Any action needed will be done.
Many Thanks
Dell82

 

If it were me I would replace first then figure out what caused it you dont want it to blow out on you. I have been told that that happens when the cords in the tire beibin to weaken or start breaking dont know if this is true or not. Your safty is more important

 

Replace now.

 

The explanation is that you drive farther going left than you drive going right. Also there are greater forces making a left thru an intersection, because a right turn is done slower, and a shorter distance.

Think of a long left bend in a country road- - your return trip is a slightly shorter right bend. Now a long right bend. . . the return left is longer.

This is reversed in countries that drive on the "wrong side" !

The scalloping or cupping is a different issue and could just be the way the tire wears.

 

Nobody has mentioned that tire rubber goes bad after about 4 years, which is why you hardly ever see tire warranties longer than 48 months. After that the rubber starts to harden and rot and you get funny wear patterns like you are experiencing. If you haven't replaced the tires since 2004 that's your problem. You could also have bad wheel bearings or need to rebuild the forks but you can check those things when you have the wheel off to replace the tire.

 

X2!

As the uneven wear starts to affect road grip you can get a "speed wobble" at high speed. And that, as everyone here can tell you, can be a quick ticket to serious grief.

Other XJ experts can correct me but I advise that when/if that evil harmonic ever starts, immediately start slowdown with a very slight angle (to the right in your case).

Plus motorcycle wheels and tires need to be true, same as cars. And I suppose you might be wise to doublecheck wheel bearings and forks.

In my experience this isn't often a noticeable problem; we didn't get many bikes in my shop for this. But part of that might be that sometimes when it happens (at high speed) the bike wound up needing a lot more repair than just wheel work. Some of the riders did, too.

[don't know why I'm sounding like such an alarmist this week. Maybe the thread on very young riders started me worrying a bit. Chacal said it all with his "old, bold, but not both" comment. It's wannabe hotshot dummies like me who wind up with refurbished knees, lumpy ribs and funny-looking clavicles. But I'm mighty grateful to still be here to whine about it. :wink: ]

 

Odd front tire wear such as feathering and scalloping are "usually' attributable to problems with the Front forks. and their lack of damping/ or rebound
Time for a Fork Rebuild.. Then New tires which a prudent rider changes in pairs.

 

Danilo we checked the damping and it was set to one on both sides. Air pressure is 14PSI. Pushing down when riding or stationary seems good. No instability noted at 80 MPH on the super slab. I travel 48 Miles a day to work.
Any other suggestions?
Dell82

 

How often do you check tire pressure? Running low on a tire just a few times will cause some strange wear.

What model of Dunlop is it? I see a lot of tires come through my shop and it seems that Dunlops do this worse than any other brand - on both touring and sport tires. Weird!!

I've also heard that the balance can affect this. There's a product called Dyna Beads that has some great testimonials for tire balancing (see link - www.innovativebalancing.com ). I just ordered some for my sport bike. I'm going to see how they work.

 

Never heard of them before, but they sound good on the website. And cheap. (Any idea how they distribute and bond within the tire?) Eager to hear your report after trying them.

 

NO mate .
Improperly set Compression and Rebound settings..IS the accepted/proven reason for scalloped /feathered front rires. Incorrect compression results in scalloped, wrong rebound in fearthered
Given that your (our) forks are little more than chrome pogo sticks in design..with no adjustments whastoever.. sad but true....One can only assume they are seriously worn out.
Bouncing yr forks up and down is no test of any sort except for the presence of a spring and 'some' oil.
Again.. rebuild them Using New parts... then ..see how the tire wears.

PS Dyna beads are the equivalent of Penis enlargement creams Some believe wholeheartedly..while many just laugh.

 

Read this: http://tinyurl.com/dnr2 My last tire did this and the replacement hasn't. Just a common thing with bikes due to the way they grip the road.

 

So true. My Explorer cupped 2 sets of tires. Nobody at the tire store or Ford dealer could figure out why. Finally replaced air ride shocks - one of them was way beyond worn out, the other 3 were pretty much ok. No more problems. Seems weak shock allows the tire to bounce excessively and causes "cupping" or "scalloping" I never felt the vibration but it was there. Rotating tires through the weak shock eventually caused them all to cup.

 

I have to admit that right and lft turn explaination was entertaining if nothing else.......What??

 

Your front tire wears more on the left half more because of the pitch of the road also.