Tires "Scalloped"

I've been running Michelin Pilot 5's on my 2014 RT for a year. Despite them "not being recommended" by Michelin for the RT, so far I've been very pleased. Apart from the road noise (which is noticeable) that others have mentioned they have worked well for me.

I have 6,500 miles on them (which is pretty much all that I ever got out of Pilot 4's) and am about to head off for a trip for a week so I checked them out. I am pleased to say that there is plenty of tread depth left on them, but both the front and rear are really "scalloped". How does the scalloping affect the tire (other than increasing the above-mentioned road noise)?

Am I good to ride with these until the tread wears, or does scalloping affect their traction and/or safety?

My Pilot 4's usually ended up being scalloped towards the end of their lifetime, so I have been running my tire pressures +2psi over the recommended to "reduce" scalloping. It doesn't seem to have helped and/or may have made it worse?

How long is the trip?

When I bought my bike (used) early last year the dealer put an inexpensive set of ContiMotions (non-GT-like sidewall). They were fine traction-wise but they really started howling from the scalloping (which isn't affecting your road noise, it is the cause of your road noise). That was the first indication to me that there might be something to this GT-strength sidewall stuff.

I've got Bridgestone Battlax T31 GT's on it now and two thousand miles later they look like they are brand new and the bike feels like it's much better planted than it ever did. I'm thinking that most of that is having a stiffer sidewall. The bike used to kind of wallow in the turns, which I thought was the shocks wearing, and now that's completely gone.

bobs_one said:

Am I good to ride with these until the tread wears, or does scalloping affect their traction and/or safety?

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You should be fine.

The correct tires operating at the correct inflation pressures will go a long way toward alleviating scalloping tires. Remember there are only two small patches of rubber separating your butt from the pavement. Not the place to save a few bucks.

Friedle

I have gone through several sets of the PR series of tires and most were taken off when they scalloped bad enough that bike wouldn't hold the twisties.

I was getting about 10k-12k (kilometers) per set and was comfortable with that performance.

My last set, I dropped the tire pressure 2 PSI below the minimum recommended for single up riding and I just changed them at 16K (kilometers).

My 07 RT, 08 R12R, FJR and 17 GSA all tended to scallop the front tire. All responded positively to increasing the tire pressure to 40 PSI. I haven’t had any scalloping since I began using the increased pressure. However, in my experience once a tire starts scalloping there is no reversing the process.

Is scalloping really bad? Or is it just a measure or indication of how we ride?

It clearly is only uneven ware in small areas of the tire. Over the width of a tread block, usually off center on either or both sides.

Is this due to to low tire pressure?...many avoid this by keeping pressures on the high end of spec.

Is it due to dual compound tires and more aggressive riding in the twisties, wearing the softer compound out faster? Seem so to me.

On the front, is it due to consistent heavy braking?

On the rear, is it due to consistent heavy handed application of the throttle?

Other than low pressure, all this seems pretty normal for soft compound motorcycle tires. (Do we really want hard 50,000 mile car tires?)

If my tire pressure are in spec, I just ride the tires out...replace them when worn out.

If seeing scolloping really bothers, buy harder compound tires...they are usually cheaper too.

vtbob said:

Is scalloping really bad?

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Motorcycles in New York state must be inspected once per year. You may get an inspector who fails a tire based on it being scalloped.

I had no problems with scalloping on Anakee III's or PR4 Trails on my wethead GS and had no problems on my 2003 R1150RT. I ran the front tire a bit higher than what BMW called for.

I know I’ll get push back here for this comment, but in my and several of my friends experience, dynabeads, if properly installed, pretty much stop the cupping. But must be utilized from start of use. Will not do much good now. Your choice when installing new tire, and must be installed with no possibility of contacting tire lube, soap film etc when setting the bead. Otherwise clumping will occur and you’ll hear the comment about snake oil etc. I’ve had them in Pr 3s on my k1200 and found the ride smooth as silk at 120 mph riding n Montana and no cupping during the life of the tire. Used them in Heidenau’s and although a work to bead with minimal tire lub, experienced the same results. Have them in my front 1200 Yamaha Tenere in a Michelin Anakee three adventure but only 2000 miles on them so far. Didn’t put anything in n rear nor did I balance rear statically just to run a test to see if it makes a difference or not. Should put another couple thousand miles on them over four corners rally. Your choice obviously, and like I said, there will be much push back here on my comments. BTW up to this point in my ride life, usually a 15000 to 20000 mile annual rider.

Michelin=the most overrated tire for your RT, IMHO of course. I think it's primarily brand reputation, the lovely ornate siping, and that's about it. PR4GT's were on my '16 RT new, and they got very significantly scalloped in well under 2K miles at BMW's recommended pressure. Of course we learn the work around is accept the to shrunken contact patch that comes from increasing pressure by 10% or so, to 40psi on the front. That does help retard the rate of cupping but geez do you really like to pay top dollar for an ST tire and then have the bloody thing scallop like that? Why? Inevitable? Not in my experience. Continental RA3 GT has been so superior to PR4GT, Angel GT, and Metz Z8 for me I'll never use another tire model again: best turn-in and line holding, handling, no howling in turns or other undesirable noise, shape retention, zero scrub-in required, and traction so good my strips shrunk from increased confidence alone after 4 other sets of other tires tired, and no scalloping at stock psi. They were recommended to me by an uber aggressive rider who uses them on his R9T (non GT variant).

Change from Michelins

ncpbmw1953 said:

Continental RA3 GT has been so superior to PR4GT, Angel GT, and Metz Z8 for me I'll never use another tire model again.

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Thanks - I know tires are subject to a variety of opinions (only second to motor oil), but I'm at the point where I think I will try something other than Michelins. What kind of mileage do get from a set and do you ride only one-up, or some two-up or what?

bobs_one said:

Thanks - I know tires are subject to a variety of opinions (only second to motor oil), but I'm at the point where I think I will try something other than Michelins. What kind of mileage do get from a set and do you ride only one-up, or some two-up or what?

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I've got 6,000 km on my RA3s and they look like new. One-up sport-touring with about 20 kg of luggage on a K1200S, usually at about 110-120 km/h. I run them at 36 psi front and 42 rear.

bobs_one said:

Thanks - I know tires are subject to a variety of opinions (only second to motor oil), but I'm at the point where I think I will try something other than Michelins. What kind of mileage do get from a set and do you ride only one-up, or some two-up or what?

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One up. I have ridden these w/ luggage loaded in heavy rain as well. I can give you an estimate is about it because the first rear RA3 took a big deck screw at 5,710 miles so I replaced it. When this happened I measured tread depth in standardized points on the tire w/ 5,710 miles on a new RA3 I had installed. From this I projected out around 10,500m should be in the ballpark if that same tire made it to end of life. That is about what the PR4GTs gave me. I have ~2,500 on my replacement rear now. Here's another thing that really struck me I just now remembered: when I picked up the bike w/ the new rear RA3 I was struck by the fact it felt absolutely no different than the original tire at 5,710m that took the screw. In my experience new tires always felt much better than the spent ones just replaced. Maybe that's more true w/ the front tire I don't know. My front tire has 8,210 and still looks and feels great.

Tire Scalloping

Scalloping, or what is more appropriately referred to as cupping, is a sign of a suspension setup problem. I had a similar issue on my 2009 K1300S's rear tire which was a Continental SportAttack 3. It was related to low speed damping as I had the suspension setting dialed in for one passenger without luggage when I was carrying two fully-loaded side cases and a textile top case stuffed full of gear and clothing (probably 40 - 50 lbs. of additional weight plus a 15 lb. "rider premium" for what BMW calls the average rider (185 lbs.)). The following is a lengthy video on the topic of unusual tire wear but I found it so fascinating and insightful I watched it twice. Hopefully you find it useful as well:

www.onthethrottle.com/howto/dave-moss-unsprung-tire-wear/

Good luck with your diagnosis!

Kent

bobs_one said:

I've been running Michelin Pilot 5's on my 2014 RT for a year. Despite them "not being recommended" by Michelin for the RT, so far I've been very pleased. Apart from the road noise (which is noticeable) that others have mentioned they have worked well for me.

I have 6,500 miles on them (which is pretty much all that I ever got out of Pilot 4's) and am about to head off for a trip for a week so I checked them out. I am pleased to say that there is plenty of tread depth left on them, but both the front and rear are really "scalloped". How does the scalloping affect the tire (other than increasing the above-mentioned road noise)?

Am I good to ride with these until the tread wears, or does scalloping affect their traction and/or safety?

My Pilot 4's usually ended up being scalloped towards the end of their lifetime, so I have been running my tire pressures +2psi over the recommended to "reduce" scalloping. It doesn't seem to have helped and/or may have made it worse?

Click to expand...

I have a 2016 RT and got almost 13,000 mi on my 4's before replacing them recently. No scalloping or cupping. My 2000RT with PR2's cupped(front) after 2000mi.

bobs_one said:

I've been running Michelin Pilot 5's on my 2014 RT for a year. Despite them "not being recommended" by Michelin for the RT, so far I've been very pleased. Apart from the road noise (which is noticeable) that others have mentioned they have worked well for me.

I have 6,500 miles on them (which is pretty much all that I ever got out of Pilot 4's) and am about to head off for a trip for a week so I checked them out. I am pleased to say that there is plenty of tread depth left on them, but both the front and rear are really "scalloped". How does the scalloping affect the tire (other than increasing the above-mentioned road noise)?

Am I good to ride with these until the tread wears, or does scalloping affect their traction and/or safety?

My Pilot 4's usually ended up being scalloped towards the end of their lifetime, so I have been running my tire pressures +2psi over the recommended to "reduce" scalloping. It doesn't seem to have helped and/or may have made it worse?

Click to expand...

I have run Michelin PR 3's, 4's, and 5's on my '03K1200RS and until I ran the 5's I never had a front tire cup. I got about 9K from the 3's and 4's and 8200 on the 5's; the front tire cupping on the 5's only began during the last thousand miles. When I replaced the 5's the rear tire probably still had another thousand or so left on it but the front tire was on the wear bars.

When I put the PR5's on I really wanted a set of GT5's but they weren't available yet. I queried Michelin several times as to what their weight break point was for fitting the GT5's vice the PR5's..... no answer. I replaced the PR5's with a set of Pirelli Angel GT "A" Spec's (if you need the Michelin GT then you need the "A" Spec Pirelli) at the recommendation of one of my BMW club's high mileage riders. I'm pushing 73 now and don't ride as aggressively as I used to so I'm looking more now for longevity than absolute grip in a tire (while still having enough grip for occasional visits to the edge).

Regarding tire pressure: When your increase your tire pressure from the manufacturer's recommendation you are decreasing your contact patch... are a few extra miles worth a loss of grip? Remember to adjust the recommended "cold" pressure of your tires for ambient temperature. A good rule of thumb is to increase the recommended pressure by one (1) psi for every ten (10) degrees F over 70F. It was 100F in my shed late yesterday afternoon when I checked my tires for today's breakfast ride so I increased 36psi F/42psi R to 39psi F/45psi R.

Tire choice is probably the most subjective part of equipping a motorcycle. From my perspective unless you are a very aggressive sport rider go for all the sidewall stiffness available. If you stay with the Michelins definitely consider the GT5's over the PR5's.

Yes, scalloping affects the performance of the whole motorcycle and not just the tires, especially on a bike loaded to travel. A scalloped tire(s) causes the suspension to work harder which in turn aggravates the scalloping while degrading the handling characteristics of the bike.

As for the trip.... the difference between "probably ok" and "good to go" is up to you.

Truth be told I would imagine most of us have overridden a set of tires at one time or another (with widely varying results/stories!).

VIEJO said:

It was 100F in my shed late yesterday afternoon when I checked my tires for today's breakfast ride so I increased 36psi F/42psi R to 39psi F/45psi R.

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At ANY ambient temperature, I believe your rear tire is now over-inflated.

PLUS,

Was it 100F this morning when you went for your breakfast ride?

https://motorcycle.michelinman.com/motorbike/tips-and-advice/tyre-pressure-for-motorbike

BC1100S said:

At ANY ambient temperature, I believe your rear tire is now over-inflated.

PLUS,

Was it 100F this morning when you went for your breakfast ride?

https://motorcycle.michelinman.com/motorbike/tips-and-advice/tyre-pressure-for-motorbike

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VIEJO followed the recommended procedure for temperature calibration to 68 ambient so his 45psi is where it should be for an ambient of 100F in his garage. Return to ~68F and voila psi will then be right around 42. Were he to set psi to 42 at 100F ambient he would then be ~39psi at 68F ambient so would be under-inflated which is the universally suggested worse condition than what you're suggesting.

ncpbmw1953 said:

VIEJO followed the recommended procedure for temperature calibration to 68 ambient so his 45psi is where it should be for an ambient of 100F in his garage. Return to ~68F and voila psi will then be right around 42. Were he to set psi to 42 at 100F ambient he would then be ~39psi at 68F ambient so would be under-inflated which is the universally suggested worse condition than what you're suggesting.

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Sorry, you're wrong. Did you even read the link I included?

One inflates one's tires dependent upon the ambient temperatures in which you are running. If one is running in 100F temps then one might inflate one's tires to 42 psi or whatever the bike's manufacturer recommends. If the next day one is running in 68F temperatures, the tire pressures should then be adjusted (cold) for that temperature.

But....you can do whatever it is you like.

BC1100S said:

Sorry, you're wrong. Did you even read the link I included?

One inflates one's tires dependent upon the ambient temperatures in which you are running. If one is running in 100F temps then one might inflate one's tires to 42 psi or whatever the bike's manufacturer recommends. If the next day one is running in 68F temperatures, the tire pressures should then be adjusted (cold) for that temperature.

But....you can do whatever it is you like.

Click to expand...

If you set the correct cold pressure at 20C (68F) and none leaks out the pressure will remain correct as the tire heats up and cools down. If you set the adjusted pressure per the chart at ambient 100F if temps cool down to 68 by morning you will find the recommended pressure within 1 psi. And that goes for any increased or decreased temperature.