af2nr

What does everyone recommend as far as a minimum max tire width for a gravel/cross bike? I like the geometry of the Grade and Diverge but they seem "limited" to a 35mm tire, or at least thats what is "recommended". On the other hand the CX bikes seem to have a racier geometry but more tire clearance. SO, how much is too little or too much?

Kopsis

It all depends on what kind of riding you plan to do. For some, "gravel" means well-groomed unpaved roads. For others, it might mean something a lot uglier. CX racing has its own unique requirements. In most cases, 35 is plenty. On nice gravel people routinely ride 28s. For CX, bigger than 35 will usually slow you down. It's only the extreme stuff where you might want more (and then you have to ask yourself if a full-rigid MTB might be a better answer).

flargle

I know a really fast guy who swears by 40mm Clement MSO for dry courses. Because of the UCI 33mm rule and the trickle-down effect, you don't see many fast guys going wider than that, but if the rules were relaxed, I think you would see tires pushing 40.

The wider the tire, the lower the rolling resistance. The trade-off is weight and aerodynamics.

DirtRoadRunner

I like riding 42's - and personally would not get a gravel bike that took a max size of only 35's. Fatter tires allow for more excursions on singletrack, as well as bombing down rocky descents with a bit more confidence. But, it all depends on the kind of gravel you ride - some of the roads around here are hardpack and are rideable on 25's, while others are very rocky and require caution even with a 42.

My bike will only fit 42's - which is unfortunate because I'd like to try the BG Rock 'n Road tires, which only come in a 43.

Wilfred Laurier

Softer and rougher surfaces are more difficult on narrower tires. Heavier riders often find it easier on wider tires.

And many bikes have limited clearance for tires in the fork and rear triangle.

af2nr

The clearance is what I am asking about, I want the most options dependent upon the course. How much is the question?

Wilfred Laurier

Depends on the surface you are riding on. The well maintained gravel road I ride to work is fine with 32mm tires in the dry season (some people use narrower), but the unmaintained roads I ride for fun are iffy with 38s.

Gus90

I've found 35's to be plenty adequate for the task. Even 32's are good.

keepamonte

I would also note that if you're riding a carbon chainstay bike, be very careful with tire clearance on muddy gravel rides. Mud/gravel/stones accumulates very quickly and can erode a chainstay. My Redline CX can accommodate a 38 but very little clearance on the chainstay. After a grueling 40 mile ride in the muck, I noticed the drive side chainstay eroded to the bare carbon when cleaning. I applied 3m clear tape and reduced my 38 to a 35. But unfortunately even a 35 will probably do similar damage. This obviously leads to a dilemma on my 3 upcoming 100 mile gravel races if its raining or the course has had significant rain. This is why I'm leaning towards a steel or Ti frame.

cs1

After reading all the reoplies so far (9) I agree with you on steel. A Surly Cross Check or Straggler might make a good fit. You can get a CF fork to save a pound or two. The total race weight is definitely going to be more than your current CF rig. Good luck on whatever you choose.

TGT1

The BD Ti cross bikes will handle a 42

There's a huge difference between 32's and 42's on unmaintained fire roads.

af2nr

Thanks for all the insight and replies! This is becoming one of the toughest decisions I've had to make bike wise, so many options and so many variables! The Niner RLT is still a consideration and while I like some of the "custom" options the price difference is quite hard to justify but maybe it's viable?

keepamonte

Stay in touch with Frostbike 2015 | Feb 20 - Feb 22 event. Salsa Warbird has a carbon bike coming out with 43 tire clearance as well as a smaller aluminum frame clearance of 42.

DirtRoadRunner

I would get the AWOL, rather than the Diverge, unless you plan to actually race CX on it. It would definitely be a better gravel rig - and you could tour on it or ride singletrack. It definitely looks like a great multipurpose bike. The X PLORER version even comes with panniers. You'll never regret getting a bike with too much tire clearance for mixed-terrain riding.,

keepamonte

I would seriously consider what the main purpose of this bike will be. I race cross and am signed up for three 100 mile gravel races this spring. I have an awesome 16lb carbon CX machine that is very nimble and quick, But on gravel rides, it sucks the life out of me if I'm on it more than 3 hours. that race geometry makes a difference! I am limited to 38's on front an rear when dry, if the weather creates peanut butter from mud and gravel, I'm screwed due to my carbon chainstays and the wear from mud/gravel. If I race more gravel, I will surely get a steel or Ti frame with at least 40-42 clearance, longer head tube, and longer chain stays. I'm a roadie so I love to climb but I don't think I really want one bike to race CX and gravel(yeah, I know it's all about the money too). Just throwing this out there for you to chew on.

af2nr

It will be a multi-puprose bike for me, it may actually take the place of my road bike as well? The intended purpose would be charity rides, gravel rides/racing, and possibly cx racing as well. Maybe I am expecting too much from one bike but I am searching?! Thanks for the info on the new Salsa too!

Kopsis

CX racing is significantly different than the other uses you mention. If you're talking about a race or two each season for fun, then focus on your other needs and what you end up with will be adequate for the occasional CX race. I you're talking about a dozen CX races or more each season and a desire to be competitive, you want a dedicated CX bike and probably something different for on/off road endurance events.

RocThrower

For what it's worth I have 35mm Winter Marathon Studs on my Grade right now, with fenders. I still have about 4-5 mm of tire clearance on both sides of the tire at the tightest spot, which is the at the chain stays. I'll probably put some X'Plor USHs on them once the ice and snow is totally gone.

justin1138

+1

79pmooney

More on gravel vs CX. FOr CX, a high bottom bracket clears stuff. Not as nice a ride, but nice and CX are not usually in the same sentence. The huge tire clearances aren't for huge tires, they are so mud buildup doesn't slow the bike. A really serious CX bike will not have fender eyes; it is a racing machine.

And for gravel grinders: if you want to see what the ultimate gravel grinder looks like, look at any ancient Tour de France photo. Those are what the world's best framebuilders created to go fast on gravel when all the money was on the table. (I am now riding a 40 year old Raleigh Carlton International, clearance with fenders for 37c easily, 72 head angle and a few miles of fork rake. Take a B&W photo and it would look right 30 years before. And off road? Like it was born for it.)

Ben

fietsbob

Like NASCAR has gages for the shpe of the cars, UCI has a Max Tire gage to pass/fail your tire choice, but an informal GG with your buddies does not have to Comply.

So af2nr, how wide is your Frame clearance where the tire is closest?

09box

I'd say probably a 32 or 35 is the sweet spot.

af2nr

I understand that there are geometry differences between cross and "gravel/adventure", BB height, chainstay length, etc. CX would be something for fun and infrequent compared to gravel/dirt road riding and road. If I could "get away" with 35's the Diverge makes a nice compromise, the Renegade/RLT can go up to 40's, the Grade seems somewhere between? 3 of those 4 are carbon, benefit or drawback could be debated. I'm looking to replace my Emonda with a bike I can ride most anywhere and participate in most anything with. That new carbon Salsa Warbird is nice but it's low spec'd for the money compared to others in that price range?! Thanks again for all the insight and replies, keep'em coming!

DirtRoadRunner

The Raleigh Tamland has pretty nice geometry, and would make a great gravel bike, and it clears fat tires. It is steel, so it isn't light, however unless you are actually racing this really should not make much more of a difference. The Ultegra version has a oddly-spec'd 52-36 crankset, while the 105 version has a much better 50-34 crank.

I wouldn't get rid of your road bike, though - if you plan to participate in fast group rides, or just go out on a solo hammer fest, a true road bike will always be faster than than a compromise gravel/cx/touring bike. The difference is noticeable. If you have the room, two bikes are the way to go - one for hammering down paved roads, and one for everything else. I love my Space Horse gravel bike, and would definitely pick it if I only could have one bike, but my CAAD9 is definitely better for riding fast on paved roads.

bikemig 

+ 1.