Unfortunately I finally have a big con for the 260/40 R18 Cruisetec tire on the Fat Boy 240 rim.
Wet grip is genuinely awful. The tire has notably less wet grip and breaks the rear tire loose more easily on wet pavement than compared to my Bridgestone Battlecruise H50 240 tire.
And this is comparing a 2 year old and used H50 vs less than year old and less than 5000 miles cruisetec.
The center tread stripe has so little grip in wet I was able to break the rear loose accidentally yesterday adding a little bit of throttle to beat a yellow in the rain(wasn't going to be able to stop in time for the red).
That was with 2 people and full tail bag (20~30lbs?).
I'm genuinely concerned about the wet performance of the rear tire.
I love the Tourance NEXT2 150/70ZR18 front tire, but I may need try the cobra 260/40 18 next time if it has better wet grip.

 

Do you think the rim width has anything to do with it? I'm not sure what the width difference is for a rim designed for a 240 is compared to a 260, but if the rim is not wide enough it could possibly reduce the contact patch. You seem to be pretty abreast of the way tires affect your bike's handling, but I am wondering if the rim width has something to do with this. I'm sure where you live, wet grip is very important.

 

The rim would affect the contact patch geometry, but not size.
Contact Patch size is a function of weight(and loading). That's why we trail brake into corners, gives you more front grip because the bike's weight is on the front tire spreading the contact patch out, and puts more weight per area loading into the contact patch.(Depending on PSI)
Rim and tire design would change the contact patch shape but not total area.
The marketing page does say they specifically designed a linear contact patch.
What that means I dont know. Linear could be along the tire(effecient but poor acceleration grip), or across the tire(excellent acceleration and cornering grip.)

I'm willing to bet it's compound design and chemical make up.
The problem I seem to have with wet grip tends to show up when the bike is upright, where it would be sitting on the central stripe, which is very hard and does not become as sticky feeling when warmed up.
This tire doesn't hook up as well in the dry like the H50 which is a notably good drag racing tire(if you arent doing slicks).

The H50 may be a particularly grippy tire and now I'm on a normal wet handling tire again, or something like that.

We know the cruisetecs have more than enough grip to be thrown on a cruiser that pushes the limits, so it may just be that this is a more racing and mileage biased tire, and wet grip was lower priority.
I wonder how the 888 compares doing 0-60s and wet grip.
I'll have to simply ride like grandma in the rain, which is very easy to do.

On the contrary, I dont have anything negative to say about the Tourance NEX2 tire on the front. So far it is wearing very good, is quite soft and sticky, and I have no complaints about it what so ever.
It's great in the rain, high speed, hard stopping, and I'm quiet happy with it.

 

I ran the 888 on my Honda VTX and run them on my Road Glide. They tend to be a pretty good compromise for all situations. I can drag the boards on my RG, tour with a passenger and luggage. Even drag the boards with a passenger and luggage. I've not had confidence problems in the wet, but, of course, I'm not nearly as aggressive in the wet. Still, have never had the rear break loose in the wet unless I deliberately try to. On the Honda I rode that one like it was stolen.

 

I'm sure it's center compound. I'm no expert on traction limits, but one reason I went with cruistecs is how much everyone raves about their wet performance. **** I read on the web doesn't negate your experience... That's a trip. I haven't been in too much wet or wasn't trying to push it when I was so I don't know where the limits are.

 

Have you not ridden it in the rain until late? I'm a little surprised to hear you voicing this so late into the ownership of the tire, especially being a Washington rider.
Is it also perhaps wear related?
I don't care for the solid center on the rear tire, but also if it's worn down, that likely would reduce the water shedding of the tire.

 

So generally we're not supposed to tell people this because then people come here... but Seattle doesnt actually rain all the time.
We have a horrendous wet season that generally starts around late september, and ends around may the next year. From June to September you can expect almost entirely clear skies through out the summer.
Spring the rain tapers off going into summer so march to june is intermitted cool and clear weather that's great for running autotune sessions in.
Once the wet season hits then it's the famous constant rain that Seattle is subjected too. Considering the accident kept my bike off the road for 4 months, I had to replace the lifters, and my bars, I basically couldnt really ride all that much until late spring.
So the initial start off with the tire I was riding super safe and trying to get the tires broken in and not riding the bike much because of the bad lifter and uncomfortable bars.
Tire didnt really see any in the rain traction testing until a few days ago realistically when we got caught in a torrential downpour.

 

It might be something to do with the size of the tire. It seems that riders that are running their 180/70-16 & 180/65-16 are not experiencing the same traction in wet problems that you are with the 260/45-R18. You say you had a good experience with the Bridgestone H-50 tires, and that was not my experience with those on my 2017 Road Glide Special. I was riding through the Badlands and hit a tar snake in a curve, the front wheel lost traction and I almost went down. That is the only time I have experienced that in the 56 years I have been riding. Was it the tires? I can't say for sure, but I lost confidence in them after that. So maybe the Cruisetecs are fine in smaller sizes, but experience a wet traction problem in the 260 width. Hope so anyway, since I have a set waiting to go on the Sport Glide. Seems everyone else is reporting that they perform well.

 

Willing to try an illegal modification to the tire @FranBunnyFFXII ? If you've got a little grinder, you could cut rain grooves in the tire. That might help.
Picture below for reference.
You could cut grooves, diagonally joining the leading tips of the long water dispersion grooves across the flat center of the tire. You also might want to cut down the wear bars in those groves there near the center of the tread, they would be blocking water movement.
Cutting new grooves in the tire could create noise, and could create a wiggle due to the zig zag of the groove there across the center.

 

Interesting review comment from Revzilla writer Mark Gardiner:

"​​​​​​During the presentation, one of the Metzeler techs mentioned that the CruiseTec line was mainly developed '...for the U.S. market, so wet grip wasn’t a main factor, but we’ll also sell them in Europe, so we of course tested them in the wet.'"

​​​​​​https://www.revzilla.com/common-trea...cruiser-riders