I’ll be using this set of wheels for crits and road races locally (VERY few hills).
Which would be faster:
Zipp 303 with Vittoria EVO CX TUBULAR
OR
DT Swiss 1.2 (or some other roughly 30mm deep rim) and Pro Race 2 CLINCHER
This will be a set of wheels built on a PT 2.4 rear hub and a Zipp front in the case of the 303 or another nice front on the DT wheel set.
From what I can find, the PR2 has a lower RR, but the 303 should be more aero. Which one wins? I’m also open to other clincher suggestions, but I already have the 303 tubbie set, so if I go tubbie it’ll be on the 303 rims.
That is a good question. But, for crits and road races, I’d give the nod to the DT Swiss 1.2 with ProRace2s and Aircomp latex tube since aero doesn’t matter as much in packs and both rim weights should be about the same for quick accelerations.
From what I have gathered in crit racing it si not really the Crr that will get you (the Crr between the P2R and a Good tubie like a Veloflex carbon is really small) but the multiple accelerations that are involved in crits. Thsi is an application where rotational mass will impact your finishing position. I woudl think that with this the 303 will be ‘faster’.
Yeah, I know the 303 is a very light rim (didn’t think it was THAT light). Also, I was thinking the 1.2 was around 400g or so (but I think that is the 1.1).
I think tires would be equal with the ProRace2 at 220g + tube + rim tape about the same as a 270g tubular with glue.
So, would the Crr of PR2/Latex off the weight penalty? Crit, No? RR, yes? Price wise there is certainly no contest since you can buy, what, 3 DT Swiss 1.2s for 1 303 rim? LOL!
If the evo cx tubulars are anything like the clincher version they are VERY similar to the pr2 in rolling resistance(if not a hair better), at least from testing of them.
You’re right, no contest when it comes to price! The whole reason I am in this conundrum though is because I got a killer deal on a set of tubbie 303’s.
So for the set, I think the 303’s will be about 300-400g lighter and more aero. But, how does that factor against the Crr of the PR2?..hmmmm.
Eh, eff it, I’ve been leaning toward the 303 for a while. Plus, I’ll probably re-glue this wheelset in the fall and race 'cross on it (nothing beats a nice, light tubbie in 'cross season, right?). Either way, I got the 303’s pretty cheap, so if I kill 'em in a couple years I can always re-lace the PT hub to a different rim.
If the evo cx tubulars are anything like the clincher version they are VERY similar to the pr2 in rolling resistance(if not a hair better), at least from testing of them.
Clincher? Sure - pretty equal with the PR2 having a better “feel” and slightly more flat resistant. This is actually my combo: Evo CX 21mm on Hed Jet 90 clincher front and ProRace2 23mm on a clincher disc rear - both the Michelin Aircomp Latex tubes. Best of all worlds to me (speed/Crr, comfort, tire/rim matching aero properties, flat resistance, etc.). But the tubular is no where NEAR as fast (see chart)
Clincher
Tire Model
Crr at 7 bar
(~101 psi) Rolling Performance
at 7 bar (~101 psi) Grip Value
(higher = better)
Actual Width
Weight
Puncture
Resistance
Deda Tre
Giro d’Italia
0.0038
26.4 Watt
0.44
24.0 mm
236 g
Very Low
Vittoria
Open Corsa Evo CX
0.0039
27.1 Watt
0.45
23.5 mm
229 g
Low
Michelin
Pro2 Race
0.0042
29.2 Watt
0.45
23.0 mm
223 g
Very Good
hmm it says the puncture resistance is lower for the evo cx? I hope thats not the case as i switched over to them for the purpose of training tires! Youre right though, pretty significant difference between the tubular and clincher versions.