Max tire size - Salsa Warbird, GT Grade, Specialized Diverge, Niner RLT9RDO

I've seen/read conflicting reports.  Was wondering what size tire folks have fit into these?  

Basically, I'm sick of pinch-flatting on my Roubaix when I do road rides, so I'm going to replace it, but I'm not getting another road bike, I want a fast gravel bike that can hang on road rides with, say, 32c slicks

My Cutthroat will handle the "heavy" offroad duty, but I need something that will zip along on pavement and still be able to handle some gravel and dirt duty

again, I've seen that the RLT9 RDO can handle 40c (Nanos?), the Grade supposedly handles 35c, the Diverge 32c, and the Warbird 1.8" (45c), but I'd love to hear "the biggest" tire you've tried. 

I would suggest you add the Ridley X-Trail to your list.  It has a very endurance road geometry similar to the Diverge.  It fits up to 38c tires though the max I've run is 35c.  When I purchased it, I tried a Nano on the rear and it went on the bike but the clearance was so tight I never used that combination.

The Diverge should be good on 35c tires.  I'm not up to date on the current Warbird lineup though I thought the carbon frame was rated at around 40c.  I've got a Niner RLT Steel that handles the 40c Nanos easily though I don't like them much on the road.  I've used the bike w/Nanos mostly for offroad - probably similar to your Cutthroat.  I have used it on road w/Schwalbe Pro-One @ 28c and that works well.  No experience w/the RDO.

Have you considered road tubeless for the Roubaix?  I've run tubeless on my road bike since 2010.  I've got a wheelset for the Ridley w/Schwalbe Pro-One at 25c and they are very nice - they measure at about 28 mm on 20mm wheels.

FWIW, if  you're looking for a "fast" road bike which can also handle light gravel duty, a number of the new "endurance bikes" will accommodate 30mm or 32mm relatively smooth tires.   The high end carbon endurance bikes will be close in weight to a race bike but will be smoother and with more predictable (slower) steering.  That said, I continue to see folks riding road bikes on gravel. It's not my preference but these riders are using 28mm tires where I prefer 40mm.

To your question, the Salsa Warbird carbon is spec'd for 44mm tires and Salsa has a reputation for being conservative with the max tire width spec. Rough translation - if you don't need clearance for mud you may be able to get by with slightly wider tires.  

Hey thanks a ton for your response. I'm giving some consideration to Road tubeless But ultimately I'm going to want to take it off road on some gravel so I would prefer the versatility wider tires with some knobs. Just gives me more options, you know the whole 'Road Less Traveled' concept

NoCoGreg wrote:FWIW, if  you're looking for a "fast" road bike which can also handle light gravel duty, a number of the new "endurance bikes" will accommodate 30mm or 32mm relatively smooth tires.   The high end carbon endurance bikes will be close in weight to a race bike but will be smoother and with more predictable (slower) steering.  That said, I continue to see folks riding road bikes on gravel. It's not my preference but these riders are using 28mm tires where I prefer 40mm.

To your question, the Salsa Warbird carbon is spec'd for 44mm tires and Salsa has a reputation for being conservative with the max tire width spec. Rough translation - if you don't need clearance for mud you may be able to get by with slightly wider tires.  

good info NoCoGreg, thanks.  I'm with you, concerning the tire size.  I ride 28mm tires on the pavement because I like bigger tires.  I'm just shy of 250 lbs, so I need the extra air volume in my tires, especially on gravel.  35-38c is about the smallest I'd even consider for a mixed surface ride

Jamis Renegade will easily take a 40c (Nano 40c). I know it wasn't on the list but thought I'd throw it out there. Same with my Kona Private Jake. 40c no problem. I used the Nano 40c at first and now I'm on GravelKing 40c's and love them and the bike. 

I ride a GT Grade Carbon and my buddy a Jamis Renegade. . . We both run 40's no problem.  My Grade is fast. . . no problem running with the front pack on club rides.  Haven't really used my road bike since I got the Grade!

ChiefThomas407 wrote:I ride a GT Grade Carbon and my buddy a Jamis Renegade. . . We both run 40's no problem.  My Grade is fast. . . no problem running with the front pack on club rides.  Haven't really used my road bike since I got the Grade!

Chief Thomas, that is interesting news!  So you can run Nano 40s on the Grade with enough room for mud clearance?

I have a Carbon Warbird.
I have G-one 40 and Rambler 40 tires on there, measured those and then checked clearance by inserting allen wrenches of increasing size between the tire and the frame at the tightest spot.
This gives the following spaces:

Max space in the fork is 58mm, so if you want at least 4mm of clearance everywhere, the largest tire would be 50 mm wide.
Max space in the chainstays is 50mm, so if you want at least 4mm of clearance everywhere, the largest tire would be 42 mm wide.

Fork height is huge, as are seatstay and BB clearance.

Diverge DSW - 36 mm tire with 4 mm clearance
Diverge Carbon - 38 mm, no idea of clearance.
Before you buy a tire you need to know the real size. I get Clement MSO 36 mm, measured is 35.1, some Diverge DSW users add it - fit perfect, so when mine came in I will tell how it is, but there is 40-42 mm clearance on a bike for sure.

I'm running 45's on my RLT (non RDO). on Stans Arch mk rims. Rims are 29.3 wide. I ran 32lbs in them last week on a rough 50 mile gravel coures. Ride like firm pillows.

Apologies… I steered you completely wrong. I was thinking of the Clarence on my Linsky GR 250 not my GT grade. The grade has 35 mm tires on the back! Might get 38's in there but I would not have mud Clarence.

Had surgery for ruptured Achiles's last week so I spend too much time on internet shopping for a new bike that I couldn't use for a while anyway. I'm looking at a bike that will fit 35c tire but that will also serve as a road bike maybe with a lighter set of wheel and 28c tire. We don't have many gravel road around here and I own a FS 29er bike and a fat bike for single track duty. I don't think I need 40c tire (though it would be a + being able to run them). One of the bike that strikes me as a good all-rounder with some ability for light gravel use and good performance on road is Focus Paralane. More of an endurance bike. Not digging the color but bang for buck it's seems like a good choice. The bike even sells with custom mud gards. Frame is very light. (950g). And the ride is supposedly very smooth. Just thought it fitted OP requirement (minus 40c clearance)

http://road.cc/content/review/218220-focus-paralane-ultegra

https://www.youtube.com/watch?v=hgnBMr-WyQo

Other bikes that I look: BMC Roadmachine (but only fits 32c), Turner Cyclosys (40c alu frame), Spooky Dune (alu frame usa hand made), salsa warbird. Canyon endurance if they ever comes to north-america

thanks for the feedback, this is great stuff.  Reading what the manufacturer says is one thing, but getting it 'straight from the horse's mouth' is another thing entirely

FWIW I've seen more than one guy roll up to our local weekly worlds ride with road tires on a Crux. One I know will run one of those fat road tires from Compass, 33 or 35 or something, and still destroys all of us.

jruhlen1980 wrote:FWIW I've seen more than one guy roll up to our local weekly worlds ride with road tires on a Crux. One I know will run one of those fat road tires from Compass, 33 or 35 or something, and still destroys all of us.

\n \nAnd I've seen people ride single speed CX bikes on MTB trails and destroy the competition. Freaks don't count.

jruhlen1980 wrote:FWIW I've seen more than one guy roll up to our local weekly worlds ride with road tires on a Crux. One I know will run one of those fat road tires from Compass, 33 or 35 or something, and still destroys all of us.

Those wide road tires can actually be quite fast.  Faster in fact as the roads get rougher. Here in northern Colorado they like to use what is referred to as "chip-n-seal" which is basically tar and gravel and makes for a very coarse and uneven road surface. I have some Conti 4000S in 700x28 that measure about 31mm on skinny Mavic rim's and on chip-n-seal these tires feel faster than the 23mm and 25mm 4k's.

Disclaimer - the Conti 4k's are NOT recommended for gravel. The sidewalls are designed for fast road riding and offer minimal resistance to rocks.  DAMHIK! 

sgtrobo wrote: And I've seen people ride single speed CX bikes on MTB trails and destroy the competition. Freaks don't count.

LOL true, and one of these guys is the freakiest of freaks. King Freak of Freaksylvania. Could probably kill us all on a tricycle.

But, I've seen some less-freaky guys doing this too, and they seem to have good results with it. Combined with some of the Jan Heine studies about wide tires + low pressure (granted I take his stuff with a grain of salt), but I'm willing to try it one of these days whenever I get around to getting a second wheelset for my gravel bike. If I'm wrong then at least I'll know for sure

Anyway just figured I'd throw the Crux into the mix because the OP was looking for suggestions. (edited to add: Oh duh you're the OP. I'm smart.)