I’ve got a vote. I’ll go for it.
3 Likes
Sooo looks like new Dubnital is a worthy heir to the Race King throne. Testing the 2.4 Rapid Race now (2x pavement and 2x easy gravel so far) and 2.2 soon ish.
Probably look for it to slot in close to Rick XC Speed 2.4 in BRR land.
10 Likes
What is the software you’re using here? My Golden Cheetah wishes it could look like this.
2 Likes
It’s Python code modified from someone on Escape Collective Discord… Chung himself is in it pretty often.
I still use Aerolab too but it’s no beauty queen
2 Likes
Thanks for this. Will the fastest gravel bike now need 2.4 clearance? Yikes!!
over rough gravel / single track the fastest bike will probably be a bike like the Epic WC or Supercaliber. With or without dropbars probably depends on if the course has single track in it or how good your handling of the bike is.
1 Like
Ha… maybe depends on your location!
Oh, and I finished testing them. 2.2 rapid race next.
7 Likes
Gravel Tire Showdown ft. Drew Dillman - Thunder Burt, Race King, Dubnital, Tracer, Thunduro, Getaway
TLDW is that RK 2.2" was tied with the TB 2.1" for the fastest tire on this particular stretch of arguably cat1/2 gravelroad. They rolled down a stretch of gravel and started pedalling @300W once it flattened out for a segment that is 2.8miles long and took time measurements to assess the fastest tire. Dubnital was slower for them but they made comments about “breaking them in to get them faster” after 30min of riding or so and also that the hairs on the tire are probably not very aero.
@jkarrasch testing would suggest that the burts would be the fastest on mellow gravel. But at those speeds cda probably becomes more of a factor compared to crr. If my math is correct they averaged 25.71mph (41kph) on the RK on this particular segment.
Anybody else watched this and has some thoughts?
1 Like
I watched the video and it all seemed very willy-nilly and not scientific to me. Plus, testing on only a downhill and flat leaves me wondering the same old…what about going uphill with heavier tires? We have very mellow gravel and endless rollers where I live so I’m fairly sure that mtb tires are not the answer here. By very mellow, I mean a lot of our gravel roads are just unpaved roads with barely any rocks on them.
7 Likes
from what I’ve learned is that tire weight has a very miniscule effect. There are online calculators for hillclimbs where you can input your systemweight and targeted time for a specified segment. Adding 200g - 400g has almost no effect (0-1W) wheras the delta between slowest CX/Gravel tire on BRR to fastest is over 20W.
If you’re riding rolling terrain and not averaging north of 40kph the fastest tire for you will probably still be the fastest rolling tire for your category of gravel.
3 Likes
It’s a bit misleading as it assumes a steady effort. If you’re responding to attacks, accelerating out of corners/singletrack then weight matters a bit more. Not as much as aero, but it’s not nothing.
Not necessarily…this is been discussed many times before. The wheels are already rotating in the circumstances you describe. The additional effort to respond to attacks or accelerating out of corners is miniscule.
6 Likes
I tried some Dubnitals in rapid compound with trail casing on my mtb in the rear. Grip is insane I smashed a downhill PR by almost 2 minutes vs Sunday. On the climb my times were slower for a given power compared to fast trak as the rear.
I’m going to do some more riding on it but right now it seems like it would be a bad gravel tire.
1 Like
to add to what @Power13 said above,
it’s not nothing but in the grand scheme of things it’s almost negligible as you’re not completly stopping and then re-accelerating from 0. The marginal poweroutput (in W) you need to overcome going from 0-10mph is greater than from 10-20mph. And if you add 400g to a systemweight of let’s say 80kg, that’s 0.5% of an increase in weight, which is probably just noise in the data. It might make a difference for ineratia because the weight is on the wheels but I’m not sure if that matters all that much as you’re not only accelerating your wheels but the whole system. Maybe someone smarter than me can chime in on this topic.
@IamLeven interesting to read your experience with the trail casing. jkarasch tested the 2.4 Race Casing in the rapid compound to be almost as fast as the old, fast RaceKing 2.2 on Cat2 gravel. No data points for cat1/3 for RK 2.2 unfortunately
2 Likes
Agree, but people have weight in their head regardless of the science behind it. And what’s in your head does matter. I’ve convinced myself that the weight of my ~23lb gravel bike doesn’t matter, so it doesn’t for me. I’ve got a teammate who is a complete weight weenie and he swears that an extra couple lbs on his bike dramatically affects his performance in races. And it probably does since he feels that way.
5 Likes
Yeah to paraphrase Henry Ford: “Whether or not you agree that rotational weight matters, you’re right”.
The problem for your body is that he has to train harder or smarter to go as far as you do.
So maybe this is just a cheat code for us? 
1 Like
Not to mention it is 2.4… One might argue that if you need a tire that big a MTB might be a better choice.
The fact that it is seemly slower than a 2.35 fast trak isnt a good indicator
1 Like
There’s only so much a shop is going to put into this. Could they do a double blind perfect test that is 2 hours runtime that no one would watch until the results? Probably. I didn’t take their video as any more than a fun experiment.
Why don’t you do a better test?
2 Likes
Great, then we agree that it was only for entertainment purposes. I figured that out quickly and fast forwarded to their results because the entertainment wasn’t all that high.
4 Likes