Michelin Commander III / Bridgestone BT-046 for ST1100

[beemerphile]

Since these are both "upgrade" versions, I thought I'd document the pair. My objective is a high-mileage set of tires that don't suck. I know I will be leaving some performance behind, but with the kinds of mileage I am getting on Bridgestone T-31's I'm leaving my behind behind. The Commander III is an upgrade to the Commander II and the BT-046 is an upgrade to the BT-045. Both promise better mileage than the earlier versions. Both bias construction. Stock non-ABS sizes 160/70-17 rear and 110/80-18 front. Here's the set...

Impressions so far... Both are heavy tires. I didn't notice a difference from the weight in the rear, but the 3 or so extra pounds in the front did have an effect on suspension compliance over rough ground. It wasn't bad, but the degradation is apparent vs. the T-31. Otherwise, the set tracks and corners well, and is without bad habits. Both tires are quiet. Good cornering confidence. Steering isn't as precise as the T-31, but it is at least as good as the G547. Hands-off straight-line stability is good with no hint of headshake. It is hard for me to rate installation difficulty any more because the Weaver machine doesn't complain. However, I'd say the Commander III is on the order of a BT-020R or ME880 in stiffness. The BT-046 went on easily. In fact, I rolled on both beads at the same time with one revolution of the machine. I can do this with some, but not all front tires. I haven't been able to do it with wide rear tires. I mounted the BT-046 backwards vs. the rotation arrow. The sidewall says "Rear Use Only". Silly tire engineers. If you are going to do things backwards, just go ahead and do them totally backwards. All factory advice that I have found (only Avon) suggests reversing a rear tire when running it on the front because that is the direction of tread ply overlap and because braking is the main force on a front tire vs. acceleration for the rear tire. The rear took 2 oz. (eight segments) to balance and the front took 1/2 oz. (two segments) to balance. Only the front had a stem location dot, but I didn't use it because I have pre-balanced my wheels.

 

[970mike]

Looks like you have found some tires that will give you some good mileage. Keep us posted on your likes and dislikes on these and mileage.

 

[The Cheese]

Interesting. Curious the mileage you get. Keep us posted.

 

[ST1100Y]

I mounted the BT-046 backwards vs. the rotation arrow.

ehhm... what about the drain functionality of the thread pattern now?
And what's wrong with the decent G547/548 combo (which was actually designed with/for the 1st gen ST1100)?

 

[beemerphile]

ehhm... what about the drain functionality if the thread pattern now?

For moving the water out, it works as well either way. When the tire squashes the water, it goes out the channel. People mistake the design of the tread as important for which way the water takes off when rolling over it. Who cares which direction it goes - only that it leaves. It is a path for the water to take to get out of the way and the tire trying to get to the pavement provides the pressure to expel the water. What the tread pattern DOES influence is wet traction. Then we go back to the main forces on the rear tire being acceleration and the main forces on the front tire being braking. For the tread to be most traction-effective for braking, it would need to be reversed. It will work either way for traction as well, but better if used as recommended. The tread overlap is the other consideration. Installed as recommended, the force application works to close the overlap rather than open it.

And what's wrong with the decent G547/548 combo (which was actually designed with/for the 1st gen ST1100)?

They are still decent, but now thirty years later, there are better performing tires available in the recommended sizes. Bridgestone T-31's way surpass the OEM tires in performance. I did not get acceptable mileage from them though, and I got less than 8000 miles from my last G547. I am trying to beat that with this setup. It may succeed, or it may fail. I am not trying to sell this combo to anyone - I am documenting my experience. In the end it may only prove that I am a dumbazz. I've had experiments end that way before.

 

[ST1100Y]

For moving the water out, it works as well either way. When the tire squashes the water, it goes out the channel.

Watching a docu (methinks it was Micheline though...) about tire MFG, production techniques, etc... they spent quite some time on that issue...

I got less than 8000 miles from my last G547.

I get about 12,000km/7,500miles out of them (one rider even claims 19,000/12,000), but any other tire avail over here will barely make half of that...
But bear in mind that I'm legally bound to the 2mm thread depth as my mileage limit over here

I am trying to beat that with this setup.

I'd figured that

 

[beemerphile]

Watching a docu (methinks it was Micheline though...) about tire MFG, production techniques, etc... they spent quite some time on that issue...

Was it a documentary on Michelin automotive tires or motorcycle tires?

Nearly all automotive tires are symmetrical non-directional tread and are designed to be run in either direction. So if the direction of water expulsion were important, they are not doing very much about it these days. There were some automotive tires (like the Goodyear Aquatred in 1993) that had a very complicated tread design and the marketers had great fun explaining with charts and arrows and animations which way the water was going to go. It was a symmetrical but very much directional tread with marketing directly aimed at hydroplaning resistance. I bought a set and they got very wonky very quickly as the tread wore down.



Goodyear's latest wet performance design is the WeatherReady. Its tread pattern is asymmetrical, but not directional. So, their current best wet performance tire is designed to roll in either direction. I bought a set of these for my wife's Honda Pilot. They work well, but the wet performance doesn't test any better than a Pirelli P7 Cinturato. Both are simply asymmetrical rib designs. Wildly expressive tread designs are no longer marketed for high performance in the wet - just tires that work. You don't see anything in the current designs telling the water which direction to leave.

Goodyear WeatherReady vs. Pirelli P7 Cinturato



There are two distinctly different wet performance issues with tires. One is hydroplaning resistance and the other is wet traction. Hydroplaning is addressed by tread designs that are better at getting the water out of the way. Wet traction is addressed by tread designs that increase the coefficient of friction between the tire and the road. Hydroplaning is mostly an automotive problem because of the flat contact pattern of a car tire. The narrow contact patch of a motorcycle tire is inherently very resistant to hydroplaning with or without tread. I have had many bikes slide on me because of insufficient wet traction but I have never hydroplaned one even with very worn tires. The wide contact patch of the rear tire should prove more prone to hydroplaning than the front, however the front has already plowed the water out of the way like Moses parting the Red Sea. Wet traction is by far the more important problem to be solved with motorcycles and hydroplaning is almost insignificant. If you look at the narrow sipes of a Michelin Pilot Road tire it is apparent that they were focusing on wet traction because a sipe so narrow could not channel much (if any) water. You will also notice that the rear tire tread direction (like all rear motorcycle tire tread directions) is "wrong" for this theory of directing water rearward as it leaves.



If you look at universal tires that are designed to run either as a front or a rear, the direction arrows for front and rear use are opposite. As a final exercise, if you turn a back tire tire backwards, you will find that the tread pattern is much more similar to a "correct" front tire tread direction than if you run the back tire on front in the marked direction. Running a rear tire on front is always going to be "wrong" for a number of people and I understand and respect their position. But if someone like me is intent on doing so, then running it backwards is "less wrong".

 

[ST1100Y]

Was it a documentary on Michelin automotive tires or motorcycle tires?

Nah, it was about MC tires...
They had some footage showing various tires running through water on a glass bottom to demonstrate the different water draining abilities...

But, since motorcycles hardly ride in ze rain, their chances of aquaplaning incidents are pretty slim...
(I once hit a poodle in the fast lane with about 100mph... )

 

[Larry Fine]

(I once hit a poodle in the fast lane with about 100mph... )

Well, that sounds "ruff"!

 

[ST1100Y]

In matters of water displacement/channeling the thread pattern of G547/548 serves quite well plus, me living near the alps and that, they also perform quite decent in slush or on muddy, unpaved surfaces...



One thing I consider/miss on most of the "modern" tires (or that Commander III shown at the top) these days, is the considerable wide "bald" area in the middle that won't provide much traction on named loose grounds, yet even on wet leaves in fall...
Having to get off the road onto the (wet) grass/soil due some blockage by road- or lumbering-works on numerious occasions and those tires bare any thread pattern in the center just won't get any traction there, leaving the rear wheel spinning with no forward propelling at all...

 

[red one]

Less that 8K out of the front Bridgestone G547? You guys must be way more aggressive riders than me. Last front tire change for me was at 65K miles. I now have 74K. From past experience I probably can make it another 3 to 4 K easily.

 

[beemerphile]

Less that 8K out of the front Bridgestone G547? You guys must be way more aggressive riders than me. Last front tire change for me was at 65K miles. I now have 74K. From past experience I probably can make it another 3 to 4 K easily.

My last G547 went 7,640 miles.

One thing I consider/miss on most of the "modern" tires (or that Commander III shown at the top) these days, is the considerable wide "bald" area in the middle that won't provide much traction on named loose grounds, yet even on wet leaves in fall...
Having to get off the road onto the (wet) grass/soil due some blockage by road- or lumbering-works on numerious occasions and those tires bare any thread pattern in the center just won't get any traction there, leaving the rear wheel spinning with no forward propelling at all...

I am not a fan of it either for the reasons that you mention plus the fact that you never really know how much rubber is remaining. Racing slicks have dimples in the tire to use as a wear indicator. The wear indicators on these modern tires are too far from centerline to be useful with how the tire generally wears. Why they will not put a dimple on these tires at centerline is beyond me. I have written several manufacturers asking for it. Just nice thank you letters in return. The tire companies have discovered that wet performance does not require center tread on the rear because the front tire does the plowing, and that both dry traction and mileage are improved with a solid center. Mileage and wet /dry traction are the claims that tires compete on. But at low speeds over slippery stuff, the bald tire like the Commander (and many others) loses big to one with some tread back there. It is a bag of compromises and one picks this and leaves that according to his own priorities and patterns of use. Right now, I'm just sick of constantly re-shoeing this particular horse. If I wasn't, I'd spoon on another set of T-31's. I have a new set in stock, but I wanted to run this experiment to satisfy my curiosity. I'm not calling it a win just yet.

 

[ST1100Y]

Less that 8K out of the front Bridgestone G547? You guys must be way more aggressive riders than me.

Other speed limits might be a contributing factor, more abrasive tarmac/local geology another, but the mandatory 2mm tread depth the definite limit over here; once the TWIs show up, you're already valid for a ticket as they are at 1,6mm (the MFG limit to where the tire still has proper abilities, not the legal limit...)

 

[ST1100Y]

Right now, I'm just sick of constantly re-shoeing this particular horse. If I wasn't, I'd spoon on another set of T-31's.

I read you, every time I'm scheduling a longer tour I've to check/balance tread wear on the installed set, often ending up trashing an around 50% used set prior departure, because the estimated distance will be some 8K or more, meaning I'd need to change tires while half way on the trip... in places where you just can't get tires for an ST1100, nor find a proper workshop trustworthyn doing the job...

 

[beemerphile]

I read you, every time I'm scheduling a longer tour I've to check/balance tread wear on the installed set, often ending up trashing an around 50% used set prior departure, because the estimated distance will be some 8K or more, meaning I'd need to change tires while half way on the trip... in places where you just can't get tires for an ST1100, nor find a proper workshop trustworthyn doing the job...

I keep two sets of wheels for every bike I own. If I am going on a long trip where the tires might not make the distance, I'll leave with a new set and run off the remainder of the other locally when I return. I've got some half-run tires around here that I should be using up, but it is kind of like eating leftovers - I often "forget" to do it. I've donated and installed a few of them over the years to get traveling riders out of trouble.

 

[kerbside]

I keep two sets of wheels for every bike I own. If I am going on a long trip where the tires might not make the distance, I'll leave with a new set and run off the remainder of the other locally when I return. I've got some half-run tires around here that I should be using up, but it is kind of like eating leftovers -

Same situation for me. End up with half worn rubber that I'm not eager to refit. Especially when replacing rear wheels on the GL15.
On the st11 the Commander II has easily been the best for me on mileage, maybe 10k, not sure as I had to pull it!
Hence the move to the dark side, I may put the Commander III on a wheel to try it though.
Just need to be able to get out and put some miles on!

 

[Al st1100]

In matters of water displacement/channeling the thread pattern of G547/548 serves quite well plus, me living near the alps and that, they also perform quite decent in slush or on muddy, unpaved surfaces...



One thing I consider/miss on most of the "modern" tires (or that Commander III shown at the top) these days, is the considerable wide "bald" area in the middle that won't provide much traction on named loose grounds, yet even on wet leaves in fall...
Having to get off the road onto the (wet) grass/soil due some blockage by road- or lumbering-works on numerious occasions and those tires bare any thread pattern in the center just won't get any traction there, leaving the rear wheel spinning with no forward propelling at all...

I don't think there is a tire out there that can claim good traction on wet leaves

 

[ST1100Y]

I don't think there is a tire out there that can claim good traction on wet leaves

LOL!
I meant that as in making it in/out a B&B driveway on your own power vs not making it even over the curb there without someone having to push...

 

[Ron]

I read you, every time I'm scheduling a longer tour I've to check/balance tread wear on the installed set, often ending up trashing an around 50% used set prior departure, because the estimated distance will be some 8K or more, meaning I'd need to change tires while half way on the trip... in places where you just can't get tires for an ST1100, nor find a proper workshop trustworthyn doing the job...

As long as you have been riding ST1100s, I'm surprised you haven pick up an extra set of wheels.

 

[ST1100Y]

As long as you have been riding ST1100s, I'm surprised you haven pick up an extra set of wheels.

Do you have an idea for what insane ammounts of money a decent set would come over here...
And then they're banged up, scratched, the bearing boss on the rear FUBAR...
Should have bought some new ones at Honda over 20 years ago...