Craig
I put a pair of Clement MSO 40mm tires on my Grade today and did some measuring and photographing so that everyone can make up their own minds about how wide to go. On the Grail rims and running tubeless at 35 PSI, they measure right at 40mm.

In the photos you can see the zerts sticking out from the sidewalls. Just for perspective those are average 5mm long and they rub on the chain stay and fork. Using my calipers I measured the gap between the tire and frame and fork at the narrowest part to be 3mm.

With the California drought, I plan on running these until it gets muddy. I have the 35mm USH as my backup tires when clearance becomes a problem.

Here are the photos. What do you think?
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henrypretz
Wow Craig - if it were my bike I don't think I'd use that tire.  Now I am by no means an expert, but that just seems just a bit too tight for my comfort level, especially on a carbon frame.  Chances are it will be fine.  I'm pretty much a worry wart  [smile]
I had the same situation with the MSOs on my Poprad.  Pretty much identical clearances, too.
Ultimately it's your call.  Let us know how you decide.

Henry
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Craig
Anyone want to buy a set of barely used 40mm MSOs?

The clearance was not enough even in mostly dry conditions. Gunk was always building up in the narrow gap and rubbing on the chainstay.

I went back to the 35mm USH and am satisfied with the traction and handling.

So now we know that the Carbon Grade cannot handle 40mm tires!

Who has tried anything else bigger than 35mm?
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henrypretz

We are in the same boat, Craig.  I have exactly ZERO complaints about the performance of the Clement 700x35c USH on my alloy Grade, but I am one who always wonders "what if?".  I went through the same sort of scenario with my Poprad.  I sold my 40c MSO because they wouldn't fit.
So here we sit  [smile]
My pal Susan just picked up the Specialized Trigger Pro 700x38c and it looks like a very nice choice.  However, according to the linked review, it measures less than 35mm when mounted.  
I think for now I will ride the heck out of the USHs and not think about new skins until the time comes that I really need them (did I just say that?)  There are new offerings coming out all the time and chances are someone will make one that fits your (our) criteria.
Cheers!
Henry

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stabbedintheface
I have a Carbon 105 grade and run 32mm Kenda Pro Happy Mediums.

I've even had that rub on the frame in muddy conditions.  I don't understand how others are even getting 35s in there.  Even with the 32 I have hardly 2cm of clearance.

Something wacky with my bike?  Or is the HM just wider than they say?
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stabbedintheface
Replying to my own post just so others can find it.  After a bit of research it turns out my early run GT Grade had a common problem of not having the proper clearance on the frame.  GT will warranty the frame and gave me no trouble over it 
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Enoch
Did the new frame have more clearance, like enough for 40's. THe Grade has some nice geo numbers but not being able to run 40's would be a deal breaker for me.
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the mayor

Enoch wrote:
Did the new frame have more clearance, like enough for 40's. THe Grade has some nice geo numbers but not being able to run 40's would be a deal breaker for me.

 

It depends on what "40"s you are talking about.

I run Clement LAS on Arch rims....which measure out to around 39mm.

I tired a 40 MSO on the Grail rim and it fit...but was too tight for me ( and I'd never use a tire that big)

 

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gravelswede
Any new thoughts about good tyres on the Grade (Alloy 2015, in my case)?
What about the following 700xTeied __ c:
Panaracer Comet 37 mm
Maxxis Rambler 40 mm
Stan's No Tubes Raven 35 mm
Challenge Gravel Grinder 38 mm
WTB Nano 40 mm
WTB All Terrain 37 mm
WTB Cross Boss 35 mm
Ritchey Shield 35 mm
Anyone tried using a wider tyre front and 35-38 mm rear?



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jinxz0r
This is the clement mso tubeless 36 on gt grade ultegra
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Craig
jinxz0r- Thanks for the photos, I was wondering how much clearance they would have. That looks like plenty for normal conditions. Keep us updated. There is also a GT Grade Facebook page with photos from all over the world.
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Nubster
Personally I think that any bike that's advertised as a gravel or adventure bike that doesn't comfortably fit 40c tires is kinda silly. 
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Johan Ny Toci
Nubster wrote:
Personally I think that any bike that's advertised as a gravel or adventure bike that doesn't comfortably fit 40c tires is kinda silly. 


I quite agree. BTW, GT is advertised as Enduroad (which is another silly category).

I'm happy at the moment with my Hutchinson sector 28 mm and Specialized Trigger Pro in 33 mm. Personally, I'm not interested going fatter at the moment but you never know about the future. That's why I am asking jinx0r: how does Clement MSO tubeless (36 mm) fit the tightest place in Grade (which we all do know and which is not in the photo)


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sgtrobo
Nubster wrote:
Personally I think that any bike that's advertised as a gravel or adventure bike that doesn't comfortably fit 40c tires is kinda silly. 


agreed.

lack of tire clearance is why I didn't get a Grade. With solid options coming out in the 42-43mm size, I'd think the bar needs to be raised to 45mm on a standard 'adventure' bike
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jinxz0r
@ Johan- mso 36 tubeless fits very well(maximum) I'm not going bigger cuz it enough for my riding and the trails that are here in my area. No issues of rubbing just plush no flat fun ride. Finished well I think at the Barry Roubaix gravel race.
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Johan Ny Toci
Thanks. These tyres are hard to find from the old continent.
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CraigB
(I'm not the original poster, just similar name)

I have the Performance Bike version of the Grade. My tire experience so far is that you can fit tires sufficient for my gravel needs:

Kenda Happy Mediums 35mm:  these inflate to about 38 mm in practice (Easton EA70 wheel). I had no tire rub. Tires run well both on and off road. Good in both dry and damp conditions.

Kenda Flintridge Pro 35mm (from Bikeinn.com): these tubeless tires have larger volume than the Happy Mediums, mostly from higher sidewalls. I initially had tire rub in the forks, but fixed it through reseating the tire. (Finetuning the wheel truing may also have helped.)  These tires seem a bit more sluggish on road and I'm yet to test them on gravel, but they look promising. Only downside is that they are not holding air as well as some other tubeless. I may change them to the EA70s to see if that makes a difference (they are on the Notubes Radler that came with the bike which are decent wheels)

Schwable G-One 38mm (not 35mm): I got tire rub with these and returned them. Haven't tried the 35mm
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tootall
one additional consideration matters here: the size of the frame. There may be slightly more clearance on the 60 cm I'm looking at. Any insights? I'd like a 40c. Will settle for a 38c. Probably needs fenders too... :-( May kill the ambition here.
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laserrobottime
tootall wrote:
one additional consideration matters here: the size of the frame. There may be slightly more clearance on the 60 cm I'm looking at. Any insights? I'd like a 40c. Will settle for a 38c. Probably needs fenders too... :-( May kill the ambition here.


I mounted some Challenge Gravel Grinder 700x38s on Reynolds Attack Disc wheels and they cleared with room to spare in the rear on a 60cm frame. The Reynolds rim is not as wide as the Grail, though, so the tire measured slightly under 38.
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SeanG
Has anyone tried the Teravail Cannonball on a 60cm frame?
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laserrobottime
Here's what I've tried in my 2016 60cm carbon frame:

Challenge Gravel Grinder 700x38 on Reynolds Rims: Clears easily front and rear, 3mm+ clearance all around front and back.
Clement X'Plor MSO 700x36 on Stan's Grail: Clears easily front and rear, 3mm+ clearance
Kenda Flint Ridge Pro 700x35 on Stan's Grail: Does not clear. Rubs in rear, has maybe 2mm clearance up front.
Compass Stampede Pass 700x32 on Stan's Grail: Clears easily. Measures out at 36mm when mounted and inflated to 60PSI.



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thesiehrs
laserrobottime wrote:
Here's what I've tried in my 2016 60cm carbon frame:

Challenge Gravel Grinder 700x38 on Reynolds Rims: Clears easily front and rear, 3mm+ clearance all around front and back.
Clement X'Plor MSO 700x36 on Stan's Grail: Clears easily front and rear, 3mm+ clearance
Kenda Flint Ridge Pro 700x35 on Stan's Grail: Does not clear. Rubs in rear, has maybe 2mm clearance up front.
Compass Stampede Pass 700x32 on Stan's Grail: Clears easily. Measures out at 36mm when mounted and inflated to 60PSI.


Did you try the Challenge Gravel Grinder 700 x38 on the Stan's Grail?

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forcierer
anyone tried a WTB Riddler 37? 

really like the CROSS BOSS for muddy autumn winter but for summer need something better rolling....
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urdrvideo
I am running 700x38 Panaracer Gravelkings on the front of my carbon grade, and 700x35 on the rear.
mounted tubeless on a set of Hed Belgium Black wheels I had less than 3mm clearance with the 38's on the rear... The 35's give me the piece of mind I need. I do not mind running the tire asymmetric.
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