First Gravel Bike - 40mm tire clearance adequate or deal breaker
 

I am on the hunt for my first gravel bike. I want something primarily for crushed limestone and rails to trails riding, with the capacity to handle a few gravel roads and get me to/from the trailhead on pavement. I am coming into gravel from a Specialized Ruby road bike with 105 components. My budget is ~$2000. The LBS in the area carry major brands - Specialized, Trek, Cannnondale, Salsa.

My local Trek dealer is getting in a Checkpoint ALR5 in my size (I tried the SL5); however, I need a 49cm frame and in that size the max tire width is 40mm due to toe overlap. For reference, a friend who rides gravel roads in the area rides 42mm and says he wouldn't go below 40mm. I am also looking at the Specialized Diverge Elite E5 (I tried the base E5 and the sport carbon) which would offer wider clearance; however, the drivetrain and specs are not as good and I haven't found one in my area yet.

I tried and did not love: Salsa Vaya, Cannondale Topstone, Giant Revolt Advanced. I don't have mechanical skills and am not particularly comfortable with direct-to-consumer options. My LBS is not doing full fittings right now so I am going off of what feels good on test rides. Although different geometry, the Checkpoint and Diverge both rode well on test rides.

Do I go with:

a) Checkpoint ARL5 with the 40mm clearance/toe overlap (available)

b) Diverge Elite E5 (not readily available yet)

c) some other option/ wait it out

I'd say 40mm tires will be wide enough for actual gravel roads, but on singletrack trails you might be underbiked (which isn't necessarily bad, you'll just be a little slower).

Also, rider weight is a factor - if your friend with 42mm tires is 30 lbs. heavier than you, you can run your 40mm tires at roughly the same pressure (maybe even lower) as your friends 42mm tires and have roughly the same comfort level.

Thanks tyrion Those are helpful considerations. I am 5'3", 125# give or take. My friend is a solid 30# more than me. He is also a stronger and more aggressive rider than me. Thankfully he slows up for me when we ride together :)

40 mm clearance is plenty for the riding you describe and even rougher gravel. Though wider is always better! The Giant really is a fantastic value, why was that one crossed off of your list? Maybe consider a Salsa Warbird (Apex model closest to your price) or a Jamis Renegade (Steel frane in your price range). We just sold a beautifyl Salsa Warroad in your size, perfect for your riding, but too expensive (beautiful though!).

40mm of clearance is fine, and that is a conservative estimate of what the Checkpoint can use.

I ride with 38mm tires, and it doesn't hold me back.

Thanks dwmckee I really wanted to love the Giant Revolt and was hoping it was going to be the perfect balance between specs and price, enough so that I drove several hours to try it. It rode really rough for me compared to the Checkpoint and Diverge. Maybe I missed something on the test ride, but rode the Checkpoint SL5 and Giant Revolt back to back on the same route and the Checkpoint was a much smoother ride. One LBS is getting in a Salsa Warbird in my size next month. That pushes me back into the price range of the Diverge carbon. I have been back and forth on increasing my budget, but I am leaning towards starting at a lower price point until I have a better feel for what I need/want and also to give me an all roads back-up to my road bike that I am not worried about taking on group bar-to-bar rides. Unfortunately, the Jamis dealers nearby don't have anything in my size in stock, but I could expand my search range. The Checkpoint ARL5 is in route to my LBS, so I am feeling a bit of a time crunch.

It should be fine for the riding you describe. I have ridden 20 miles of the D2R2 ride with 25mm gp5000 and weigh a lot more than you.

So toe overlap is a consideration for tire size? I guess all if my bikes shouldn't have tires then. I'd never heard of anything other than frame and fork clearance limiting tire size.

That said, 40mm will be more than enough I'd say. 35-38 would probably be fine for what you're talking about and your size.

Maybe the Revolt's tires were pumped up to a higher psi? Could've been something as simple as that.

Ive ridden 43mm Gravel King tires (actually 40mm) on my Topstone on ST. Our version on L. I. Is mostly packed dirt, some sand, occasional roots, no rocks, not very hilly. The Gravel King SK tires have a surprising amount of grip in turns as well as rolling well on asphalt. I usually just stick to straight gravel/dirt roads and use my HT in our local ST.

35-40c is more than adequate for limestone rail-trails, but I'll be the first to admit that my opinion on tire width for gravel has evolved from 35c, to 40c, and now I'm looking at 43-45c tires. Whatever you lose in weight / aero is more than made up for with better rolling speed and comfort (which makes it easier to go faster).

I would also say do not rule out the Revolt based on how it rode from the bike shop. The OE tires Giant puts on those are garbage, and it's a totally different bike with good tires.

40mm is plenty enough at your weight for the surfaces you will primarily use it to ride. You will be able to safely ride it at 35psi with tubes....a bit lower tubeless. The tires on the rim when you buy it may or may not be supple and comfortable at any psi due to a low thread count (tpi) or excessively thick rubber to prevent punctures and cuts. I say figure out the bike that gives you the most clearance you can get, while NOT giving toe overlap in the particular size you require, then figure out tires. Welcome to the Dirt.

I think 40 would suffice especially if you go tubeless and run lower pressures, which you can push that at your weight. Any chance of trying a Kona Rove in your vicinity?

Thanks @zen
I probably should have thought through a few more factors before I made a road trip to try the Revolt and came home empty-handed.

I suspected this. The Giant rides beautifully and has a very well designed frame. The tire pressure may have been on the high side, OR on the lower models they come with the horribly cheap Giant Crosscut tires, which ride just about the same flat or at 100 PSI! That is widely considered among the worst gravel tires for ride quality, though they are really tough on the positive side. For the lower-end Revolts we sell we immediately recommend a tire upgrade to a high quality tire that is better-fitting to the rest of the bike. Test ride a higher-end Revolt with the Maxxias tires on it; it will have the same frame as the lower-end carbon models and that will give you a much better idea of what that bike can ride like.

+1 for this possibility. Tire pressure is a big factor in how a bike feels! See, e.g., https://www.cyclingabout.com/lab-tes...-bike-comfort/

I agree with what others have written, that 40mm is adequate for most gravel riding. Even 38mm, which is the minimum clearance I'd recommend when considering a new drop bar bike (unless one is a road racer).

At 125 lbs, I'd guess you can ride 40mm tires around 30psi. If the bike feels squirmy, go up a few PSI at a time. (I'm around 180, and I ride 48mm tires on my gravel bike at 30 psi).

The Revolt is a good bike, but the Advanced 3 (similar price to the ALR5) is the 10 speed GRX 400 with a heavier FSA crank, so there's that to consider too.

Another bike you may consider if a Felt dealer is in range is the Breed 30.

I tried the 2020 Revolt Advanced 2 XS, which indeed has the Giant Crosscut AT 1, 700 x 38c tires.

I might have missed it, but have you considered or tried out 650b wheels?

my wife is similar sized to you and got her the Kona Rove, 650b. Tires are 47mm WTB Ventures and Very comfy. Tubeless of course.

My $0.02 on some of Iowa gravel you do want >40mm tires. I’m a big Clyde however and need that larger contact patch and tire volume.

When I test drove my Domane, for some unknown reason the tires were pumped up to what I can only assume was maximum pressure. The bike felt terrible and riding a few blocks, I lowered the pressure. Rode the bike ten minutes longer and lowered it again. Now the bike finally felt good and I eventually bought it but it always bothered me why a Trek Store would pump up the tires so high for an endurance bike.

After riding the bike for one day the stock tires had to go and they were replaced with Rene Herse tires and it transformed the bike.

There is some excellent advice so far in this thread which is nice to see. I hope you find something that works for you.

I weigh 235 and use 32c Gatorskins on gravel paths & non-technical dirt paths.

5mm of additional toe overlap isn't going to make any difference. The Checkpoint will likely work well. It's also a great bike.

Also, "gravel" means different things to different people. I do lots of "gravel" rides on 32mm tires as much of the "gravel" around here is pretty smooth.

One other thing, I assume all of these bikes are 700c based. As others have said, at your size I'd look into bikes with 650b wheels or consider spending some extra money on a set of 650b wheels. That will neatly solve clearance and toe overlap problems.

I am open to 650b wheels but haven't been able to try them yet.
Trek does not recommend 650b on the Checkpoint, which was one of the negatives on my list, although it looks like some people are using them. My search continues...

For pavement and crushed packed stone rail trails, a tire that's mid30s is fine. So a 40mm tire is definitely fine.
For gravel, it totally depends on the time of year and where you happen to ride, but a 40mm tire will be plenty for 95% of the time.
I rode 40mm gravel tires for 3 years in Iowa, Missouri, Nebraska, Illinois, and Colorado. It was fine for almost every mile of riding.

The only time I wished for a wider tire was when I would come upon half a mile of freshly laid gravel and when that happens, pretty much anything smaller than a fat tire will limit your speed.