I currently have some 25mm GP4000’s on my road bike, with the rear having about 3mm either side clearance on the frame.

Thinking about moving to 28mm at least on the rear, however how much wider is the 28mm to the 25mm is it a true 3mm or wider?

They are to go on 2019 Zipp 303 firecrests

Is there a site that records actual sizes?

Thanks

My 28s measure 26.5mm inflated to 80psi on 19mm internal width rims

Just replaced 25mm GP4000s, with 28mm GP5000s on Mavic Open Pro rims (Not sure on rim width, but rims are circa 2011).
The 28s measure 26.5mm at 70-75psi.
Barely any wider than the 25mm older tyres.

Thanks looks like I should get 28’s then

28mm GP5000 at 80psi on a 10 year old Ksyrium rim is 26.2mm.

Is there much diff in height? I’d also prefer to go to 28s but there is only just enough clearance for 25s between top of the tyre and the forks.

I think I had read somewhere that the GP5000’s are coming in smaller than the equivalent GP4000’s did for the same size. How much, I’m not sure.

I have some Reynolds AR 41 X DB wheels with a 21mm internal width and I’d love to know what the 28mm GP5000s would come out at. The frame reckons it’ll take 28mm measured, but it really doesn’t look like there’s that much clearance with the 25s I’ve got on at the moment and buying a width I can’t use would be irritatingly expensive.

My experience (backed up by what I’ve read) is that GP5000’s are closer to the advertised widths than the older GP4000’s…

Some info here:
http://www.bicyclerollingresistance.com/road-bike-reviews/continental-grand-prix-5000-tl-2018
http://www.bicyclerollingresistance.com/specials/grand-prix-5000-comparison

My experience on Ultegra rims is that the gp5000 28mm’s are the same size as the gp4000 25mm’s.

Over time, GP5000s do increase in width a bit.

My front 23mm is ~24mm on a 17mm internal rim width Hunt, year old, done far less than 12 months of outdoor riding.

My rear 32mm is now ~31mm on 19mm internal rim width Fulcrum, few months old, done far less than than outdoor. It was ~30mm brand new.

My year old (but far less than that actual use) 25mm isn’t mounted on a wheel currently, but it was ~26mm on my rear 17mm Hunt iirc.

I’d expect a 28mm to grow to ~29mm over time while mounted.

They size up far truer than GP4000S IIs, more like 4 Seasons.

I had some 25mm GP4000’s on Fulcrum Racing 3 wheels on my Boardman.

When they needed replacing, thought I’d follow the herd and go to 28mm GP5000’s.

But the rear failed to fit. It was too tall.

So I’m now running 25mm GP5000’s instead. And they’re ace!

Useful info, I’ve been swithering about 28c 5000s.
On 25c 4000s at the moment but there’s not much room to spare.

Don’t make the clearance too tight. Your tyres will pick up bits of grit and the like, and if the clearance is a mm or two they’ll get dragged against the frame.

My 32c GP5000TL measure up at 31.4mm on 18mm internal DT swiss rims, were closer to 30 when new.

For various reasons I have both GP4000 and GP5000TLs on my bike right now. On hunt aero race wide rims (19mm internal).

25mm GP5000TL 26.16mm
25mm GP4000 28.71mm

Hth

my gp5000 28m (tan walls) came up about 26mm on some hunt50’s.
i did 14miles on them before a car killed my bike 🙁

for sale if you want them 😀

I’ve got 3 sets of 32mm 5000TLs are they’re all between 31.8mm and 33.3mm. That’s on rims with 20, 24 and 25mm ID.

@mrchrispy

sent you a PM re tyres

roger

My bike wouldn’t take GP4000 28s – too tall, rubbed on the brake caliper so I got 25s. I recently bought GP5000 25s. Both narrower and lower than the 4000s but very comfortable. A bugger to get on the rim though. The hardest tyres to get on I’ve ever had. Worrying for punctures mid ride…

^ That’s a bit of a concern.

What are other brands equivalents to 4000/5000s? I’ve been using 4000s since about 2014 and not kept up with what else is out there.

Depends on the rim, as ever. I got 28mm GP5000s on Mavic rims easily.

I have a Giant TCR with 25mm 5000TL and they fit comfortably
I borrowed a buddies front wheel with a 28mm 5000TL and there was barely any space around the fork crown. Luckily the road I was riding on was not twisty as I’m sure wheel flex would have resulted in rubbing against the fork…I took it off after one ride.
(Just in case your bike is also a TCR!)

I think I had read somewhere that the GP5000’s are coming in smaller than the equivalent GP4000’s did for the same size. How much, I’m not sure.

about 15% by my measurements, quite a big difference.

I genuinely dislike these tyres

Bought a couple of tubeless version tyres, couldn’t fit them on 2 different sets of wheels. Eventually gave up and sent them back and bought some tubed versions

No problem fitting the tubes version but on a set of rims with 17mm internal width they come up at 23mm. Compared to the pro ones they replaced they look decidedly old school.