Conti GP 5000 35C: a new standard for road frames?

[adam900710]

Not a huge fan of the growing width trend.

When the trend is 23->25mm, then later 28mm, I'm fine as it really smooths the ride, and even some of my older frames can support 28mm (TCR adv 2022)

But 35mm? Not only it means a new frame, which is almost ensured to have fully integrated cable routing, but much heavier tubeless tires, much slower acceleration.

My gravel/commuter bike is already running 35mm tires (close to smooth road tire, clincher, with TPU tubes), and I can definitely feel it's way less agile on climb or acceleration.

I guess I'll stick to 28mm tires for the next few years, and check if the trend is live then.

[Takiyaki]

I'm very much up for some fatty boom batty 35mm or bigger on my next road build.
Roads round here are like downtown Mogadishu.

Theres always the option of multiple wheelsets too. Im going BBW for my long distance wheelset but sticking with tried and true 28c + 60mm deep wheels for fast rides on smoother roads. In the context of selling an old build for a new build an extra wheel set isn't too bad.

[ediryppah]

The roads I ride are usually good but I like not limiting myself on where I ride so I’m currently running 32s, and I can see myself going 35 front and rear actually. Just need to wear these current tires out.

[sandwich]

I’m on the fence about 35c tires.  I am running 35c michelins and while they are great tires and feel way faster than the 40c kendas I took off, they do not feel as fast (nor do they objectively set faster segment times) than my 28c GP5000s.  The Michis are set up tubeless and the continentals with latex tubes for minimal rolling resistance where possible. 

While the shock absorption is very good with the fat tires, there are negative effects on handling with such low pressures.  I’m running between 50-60 PSI with the 35s and ~75 with the 28s.  They feel sluggish in turns and low speed handling is particularly negatively impacted.  I also have concerns that the sacrifice they have made with thickness (the 35c GP5000s sound very thin) may make them more prone to flats compared to the other tires in the GP5k lineup.

I suspect that my happy place will be something like a 30/32c F/R combo.  I am a bigger, heavier guy (195lb) so I like the shock absorption, but I don’t want to pay the price for diminishing returns.

[wintermute]

What brands actually offer a rim with the dimensions to run a 35c efficiently?

I've seen a few 26/35ew profiles, but that will only just fit a 32 and they only seem to come in 50 deep.

There are the gravel wheelsets who seem to settle on 30-32iw and 40-41ew - perhaps this? My Michelin Pro 5 35's run to 38-39 on a 30iw elite gravel wheelset, so that would give you more space to get the tyre/rim in line.

I feel like you need maybe a 25iw 37 ew? Really, what you want is a 32 on the front, 35 on the rear, so that would bring the 32 to about 35 and the 35 to about 38 but on the rear, ok.

They also need to be deeper - 60mm as a minimum. The wider the wheel and tyre, the deeper it needs to retain boundary attachment.

[Takiyaki]

I’m running between 50-60 PSI with the 35s and ~75 with the 28s. 

Ive been similar weight as you and those pressures sound high. Though IME 5-7 PSI wont be transformative feel wise. I think tire size def helps, but the whole wheel/tire assembly (including spoke material/thickness and wheel depth) adds to the equation. I have a set of similar depth carbon spoke and steel spoke wheels on 28c GP5Ks and despite the carbon spoke wheels having more IW/lower pressures it rides way worse in the back. The wheels have different profiles as well (U vs V) so even aero is a mixed bag.

For my next build Im prob gonna get 2 wheelsets from XMCS with one being for speed/low weight and the other for comfort.

[Rolle2k]

I have XMCS 26iw 34ew for 50deep wheels for 32c GP5000S TR. They measure about 34.5mm on these rims.
I would love to have love to have rims like the new Elitewheels shown recently: 25IW 36.5EW, these would probably work fine with both 32c and 35c tires.
Would love to have like 58mm deep front wheel and 65mm deep rear wheel.

Have somebody actually tested rule of 105 in wind tunnel with wider tires? Like 30c & 32c on 25-26IW, 34EW rims... That would probably be a perfect test.

[Samuel BMR]

Never forget that you can fit 35mm tires on the 2018 SWORKS VENGE… this is crazy

Ran the PRO ONE in 34c on 25mm internal rim width and it was awesome.

However clearly not as fast as 28c tires that blow up to 31-32mm anyway.
34 to 40 is absolutely great for Endurance rides, Winter rides, Recovery rides etc…
So for your N+1 bike. But for fast group rides or races I think 30-32mm is the optimal course of action. And I mean 30-32 MEASURED. For instance my 28c Michelin Power Cup balloon up to 32,5mm (+ 4,5mm!) on 26mm internal rim width with XMCS aero wheels. So you have the benefit of wide tires, but not too wide so that the 105% rule is respected with the weight saving of 28c branded tires.
240g 28c clincher tires that measure 32mm with TPU inner tubes will save you +250g over 30c tubeless

[hubba]

I remember Zen having a rim with 28mm internal and 37mm external. I wonder if running a rim like that with 32mm tires would be better than 25mm internal rim with 35mm tires.

The 32mm tire should end up about 35.5mm and the rim would be 105% of it.

[jeanpierrebalsac]

I remember Zen having a rim with 28mm internal and 37mm external. I wonder if running a rim like that with 32mm tires would be better than 25mm internal rim with 35mm tires.

The 32mm tire should end up about 35.5mm and the rim would be 105% of it.

Could you link those Zen wheels (cannot find them)? They sound very nice for 35mm tires also. Closest to those I found are Nextie AGX rims (29mm int, 40mm ext). They look great, but the maximum depth is 45mm, and I'd be interested in something deeper.

[hubba]

Could you link those Zen wheels (cannot find them)? They sound very nice for 35mm tires also. Closest to those I found are Nextie AGX rims (29mm int, 40mm ext). They look great, but the maximum depth is 45mm, and I'd be interested in something deeper.

I remembered wrong it was xmcs wheelset. Here's a profile pic.

[biceryder]

Just tried 40c Pirellis on 32 IW Tagoola XPLRs for the first time.  Coming from 30F/32R Pirellis on 24IW wheels on my standard road bike.  FWIW, I probably could have gone with 35s, because 40s blew up to 44 WAM.  Definitely a tight fitting tire on the Tagoola wheelset.

Only one ride so far. So, I need a few weeks on them before I can give a good personal assessment.

[jeanpierrebalsac]

Yea definitely could have gone for 35.

When Zipp first launched the 32mm (or so) internal xplr rim, Goodyear made some specific (labeled size 40mm) tires for it that work well in terms of aero. When you look up the measured width of those tires on bicyclerollingresistance, they are 34mm. So they are just labeled 40 because on a 32int rim they blow up to 40.

[Sakizashi]

Tires are pretty complex engineered products. I know the ETRTO stuff isn't perfect, but let's not confidently ignore things like tread width and the tire's design and just suggest that people do things that could have serious consequences, including injury.

IMO, your best option is to follow the tire company's sizing chart. Regardless of its measured width, the number printed on the side is the ETRTO width, the one designed to be used with the compatibility chart.

For example, Continental https://www.continental-tires.com/tire-knowledge/tire-rim-combinations-etrto-standards/ When using that chart, note that the Aero 111 is narrower than the 28mm GP5000, which is roughly the same measured width as the 30mm GP5000, but if you are on a 25mm IW rim, in terms of ETRTO compatibility, the 29mm Aero 111 and the 30mm GP5000 are safe, whereas the 28mm is not. This is reflected in the tread width and the casing construction.

Pirelli and Vittoria also follow this standard for consistency. So you should consider that 35mm and 40mm road tires, unless otherwise specified, are not designed for use with rims larger than 27mm. There are tires that do vary from that, and are labeled as such on the packaging.

[jeanpierrebalsac]

I'm running 36mm tires on 32mm internal rims. At first I was apprehensive about it as well. Then after running it for a couple of months and liking it, I also saw on the Nero show's Dog or fast bike section that someone with a Canyon Aeroad was running 32mm tires on 32mm internal rims which blow up to 36mm (Nero show on March the 4th, at: 1:07:45) and racing them.

I'm sure the ETRTO have some reasons for not allowing this and thus officially one cannot recommend it. However, I am personally fine running it.