All, looking to do my first gravel race, Rough road 100 in Illinois. Most of it looks to be much like dirt roads in the country with a few crushed limestone sections and one more rough section, you can see pictures of the examples here. A lot of people off the front apparently ran Panaracer Gravel King Slick. I’d run that but I don’t think my frame can handle a 32mm tire. I think the biggest I can go is 30mm, 28mm for sure (based on OEM recommendation). So my criteria is:
Be able to go fast on the road sections which make up a majority of the race.
Not get flats on the gravel sections
Since it’s not crazy gravel racing like some are used to, I was honestly thinking of a 28mm GP4000S2 at about 60psi as I’ve run for miles in country gravel roads on my TT bike (on accident on those tires) without a problem, but wondering what the more experienced people here would recommend.
I’ve run 28mm GP5000’s (not tubless) on my road bike for a couple mild gravel races. First race, I ran around 70psi and flatted in the first 10 miles and chased (pinch flat I think). 2nd race (same course), I used latex tubes with some orange seal and was good (maybe just lucky). I ran about 85 psi on the second race. Not ideal PSI for smoothness, but I think the biggest risk of running 28’s on gravel is hitting something big and pinch flatting. I try to stay on the front or off to the side on rough sections so I can see chunk and pot holes coming. I weight about 165. I would not run 60 psi with those tires on gravel unless I was ~130lbs or lower.
Eesh, picture 3 would give me pause about running a narrower tire at lower pressure. Even the smoother-looking hardpacked portions can have potholes that blast you. And more than a few times I’ve done a gravel event where the town had recently put down a fresh layer of crushed rock that hadn’t packed in yet.
But I’m not here to tell you to not do the event, or that you have to buy another bike (although…). My suggestions:
Figure out what’s the biggest tire you can run on your frame, on your rims. Note that what you can run up front may well be different from what you can run in the back.
Go tubeless, if your rims are made for it.
Go for tires with some puncture protection – I’ve had great experience with WTB tires. If you can get a set of Byways (700x34) in your frame, that would be my choice, but if that’s too wide consider an Exposure (700x32) or Expanse (700x30).
Learn–and practice–sealing up punctures in a tubeless tire quickly. (See my thread looking for feedback on different tools for this)
Don’t be afraid to run with your bike through sketchy sections. It’s faster than riding 100 feet and having to fix a puncture. And a hell of a lot faster than walking home.
It looks like the biggest I can run is a 30 (depending on teh tire) 28 for sure. If tubed I’d run latex, not sure if that matters.
I like that Expanse. Looks perfect if it fits. The other ones i was looking at
Bontrager AW2 TLR in a 28mm - Allows the tubeless setup to avoid the pinch flats in the gravel sections running lower pressure, but doesn’t look to be much sidewall grab at all.
Bontrager R3 Clincher in a 28mm - Looks to be a good tread compromise to allow it to be fast on the flat paved sections and have some grab on the sides, but it’s tubed, so I’d be worried about pinch flats. a 28TLR would have been awesome, but looks like it’s not offered.
Bontrager R4 clincher in a 28mm - Looks a lot like a Panaracer Gravel King to give an even greater grip, but again, is tubed. Pinch flat being the concern again.
WTB expanse in 30mm
Roubaix Pro 2Bliss Ready in a 25/28 or 30/32 (would need to measure).
I’m leaning towards #4 if I can fit it, with #5 being plan B and #2 or 3 being plan C. So many choices. Now I understand why @Nate_Pearson & @Jonathan spent so much time talking about tire choices in the podcast. It’s much easier on my TT bike!
Can’t comment on 1-3, as I’ve never used them. #5 is on my wife’s road bike, and has worked well on not-so-great pavement. I recall some favorable commentary on its rolling properties from Slowtwich (I think) from a few years back.
If you can’t get the Expanse to fit, and you don’t need tubeless, another one to consider (maybe) is the Specialized All-Condition Armadillo Elite. I used to run this all the time, and found it to be super tough without being a horribly harsh ride. Lots of grip, too. Sizes include 700x28, x30, and x32 so you can fine-tune your choice to run as big as you can.
I am signed up for that race as well. I’m planning on running either gravelking slick 38s or riddler 37s depending on how much rain we get in the days leading up to the race. This is my first year for this race, but there is a couple youtube videos of it that I’ve been checking out while I’m on the trainer. The final stretchs on the hardpack limestone look fast but maybe a bit sloppy with lots of wet leaves.
I figure the front of the race will hammer on the pavement and probably slow a bit during the gravel sections. In the videos it looks like the leaders are all running relatively skinny slick tires.
The gravel in this area can be anything from hard and fast to chunky deep stuff. And there will be good sized potholes.
I have no illusions that I’ll be on the pointy end, but I figure a slow tire is faster than a puncture.
Good luck and I’ll see you there.
Can’t recommend the Gravel King 28s highly enough. I run them on my Tarmac for everything now. They’re surprisingly supple and I don’t notice any speed difference on the road vs the SWorks Turbos I was running prior.
I’ve ridden them in a 100mi gravel race (99% gravel) with some very technical singletrack, and while I had to be a bit more careful in the rough stuff I had no flats even running tubes.
I’ve been riding Vittoria Corsa Control TLRs in 30mm since october and they haven’t given me any issues. I’ve been riding them on road and Michigan gravel roads which look similar to pics #2 and #5. They definitely lean more toward the road side of things (they are marketed as a spring classics tire for Strade Bianche and Paris Roubaix) so they don’t have much tread to speak of. But if these gravel sections are very straight and flat then they may work.
TBH if I end up getting a RR100 spot, I’ll be doing it on my Crux (since it’s disc) but chances are I’ll be running something closer to a road tire than a CX or gravel tire.
I’ve been running WTB Riddler 37c’s for over a year now on various surfaces and I’ve been pretty happy with them. I haven’t had the opportunity to use them in anything muddy, but they’re pretty fast and grip well in dry conditions.
There are times when I wouldn’t mind running something wider, but 37’s about max out the available clearance on my Crux.
I’ve got a 2019 Madone SLR Disc on Aeolus XXX 6’s. I know I know, I should be riding a proper gravel bike, or something at least that isn’t as nice as the madone, but you have to ride what you got, and this bike gives me the good feels so much I just want to ride it where possible.
