i think, atleast this time around, the contis actually come up close to spec. EG, the 25 Tom tested was 26 in width. I would choose that for your zipps.

My bontragers are 27mm, so 28's would prob blow up too wide. 25 should be about right for me too, although they would probably mate to a firecrest a bit better.

Thanks.

I should have added that the Zipp 808 FC I have are the older kind (pre-2015), so a bit narrower and (as far as I rememeber) optimized around 23mm tires.

Right...so it makes carbon rim manufacturing easier and stronger (like I said), but doesn't exactly improve the security of the tire/rim interface...or else there wouldn't be the restrictions on what tires are allowed, no?

I'll need more objective data on the "better shape" claim before judging that ;-)

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Hi

Just got this today
$112.00 for two and latex tube’s

https://www.merlincycles.com/...mp;mc_eid=58cf00b7ac

Oh, i'm in that club... I haven't changed a flat on any of my bikes in over 3 years. Why.... tubeless.

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I am not sure if I missed this or not but could someone chime in please - I run the Enve 7.8 wheelset and historically ran a set of 4000II 25mm width - If i want to run the GP5000 would I need to now go with the 28mm width to achieve the same 27mm that the GP4000 gave (or is this not known yet).

It is a shame that they are not recommended to run Tubeless

EDIT: I just read on Rolling resistance that the casing seems to match measured size;



So if this is correct than the 28mm @ 100psi should equal in the 27mm range (which I run 100psi)

Enve 7.8 are tubeless compatible according to their website.

Sean,

It was mentioned earlier in this thread that Enve does not recommend the GP5000 in tubless format for the rims due to the hookless design :(

The 4.5 AR disc are the only enve road wheels that are hookless. You’re good to go with your 7.8s.

Thanks, I missed that!

Well that throws another hitch in the equation!

I guess for me it comes down to which one performs better overall now (waiting for BRR). The size questions still stands though - i'm thinking the GP5000 28mm are the old GP4000 25mm in terms of shape/size.

My GP5000 25mm measured at ~26.8mm when mounted on a rim that was 27.5mm wide with a 19mm internal width. The GP5000 28mm on that same rim was just shy of 29.5mm. Both inflated to 95 psi.

Interesting - thank you for getting that information!

I wonder if it would line up with the Enve rim being so wide. I have been on the struggle bus all day and need to quit skimming things as I misread not only this post with the Enve rims but what BRR stated about the tire width...

Regarding the size difference between the 4000 and 5000:

I just took the 23 mm GP4000s off of my wheels (Giant SLR 0 Aero 55s). They measured approximately 25.50 mm in width fully inflated
.
I replaced them 25 mm GP5000s. The new ones measure approximately 25.70 mm. Just 0.20 mm larger.

They really did shrink them. The new 25s are the old 23s. Glad I didn't buy the 23 mm new ones.

 
Interesting, thanks.

Also use Giant SLR0 aero 55mm on the P3.
Did you also make measurement for heigh ?

The 25mm GP4000 was not fitting on the front wheel with my P3 (rubbing on frame after 300km), was going to go 23mm, but if they shrink, may be not ?

I did not check the difference in height, I admit. I have to think it can't be that much. It seems to me that the new GP5000 25 is just a marginally larger GP4000 23 with lower rolling resistance

How old were your GP4000S tyres? They stretch over time. In my experience they grow at least one mm in width over time.

I've stopped using the GP4000s II tyres, as I had a few too many sidewall cuts with those tyres. I've probably binned four or five tyres due to sidewall cuts. Some cuts were too big too repair safely with a patch. Strangely enough, the old GP Attack and Force 22+24 mm have more durable sidewalls (in my experience), but I get a few more 'standard' penetration punctures. Sidewall cuts are terrible if you're running latex tubes like I do. While stiffer butyl tube sometiems work, the latex tubes peek through the sidewall holes and get punctured straight away.

I've always had issue with the side wall pealing on conti tires. Both for commuting tires and when my gf was running some of the first hot chilli tires. Has this issue been address with conti tires?
I'm a big fan of Vittoria tires - good price, ride nicely, not a lot of punctures. Can anybody comment on performance of the GP5000s vs vittoria tires?

bicyclerollingresistance.com, unbiased reviews of most popular tires. Very detailed, including puncture tests, sidewall, complete weight and measurements, and, of course rolling resistance. All Vittorias and Continentals are on the list, and he has a great comparison tool

I just got them last year. Never heard anything about them stretching over time though. That would have been noticeable on my bike since the clearance in the rear is so tight that larger tires rub on the chainstay.

Gp4000s have always been very good to me. Incredibly tough

<replying to thread in general>

Anyone have or have seen measured width data on the 28 & 33c versions of these? preferably on wide rims like enve? tubeless or non?

GP4000 s2 stretched on my front wheel. I had initially 2mm clearance, and 300km after, it was rubbing on the frame.

Too bad they use butyl tubes in all the tests

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And they don't test all available widths of tires.

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blog

It's a good resource, but I'm a little skeptical of the accuracy and precision of the way he measures force on the tire and power to spin it.

But it also provide comparison for GP4000s2 between :
butyl
butyl light
latex