It seems to me that the 21mm tubular Vittoria EVO Corsa CX when set on a the Stinger 60 and 90 needs at least 1 mm more width to fit perfectly. Maybe a Veloflex Carbon 22 mm will perfectly fit?
Can someone confirm that the 22 mm Veloflex Carbon tubular is really a bit wider than the Vittoria EVO Corsa CX 21 mm? Sometimes these sizes are just nominal.
Thanks.
Sergio
As posted in another thread (by me) and by quoting Josh at Zipp - Zipp suggests a 21mm tire for their wheels. I have not in my many years of racing and riding tubular tires ever heard so much about tires not fitting. When you say they dont fit - you mean that the glue line and the brake surface do not meet? You mean that the tire glued leaves a gap and ridge from the tire to the curve of where the brake track is? I can understand what you mean - and even fear that a tire will mount oddly and have some curve in its posture as it sits on the rim (that will no doubt cause a speed shimmy). At any case…what do you mean by not fitting well?
can tell you that we are recommending to our pro teams as well as pro-triathletes to run 21mm tires with both 808’s and 404’s, and NOT to run 18 or 19mm tires. We have seen no repeatable aero advantage in using 19 or even 18mm tires with these new rim shapes (though with the new 404, there was a slight tendency for increased drag with the 19mm tire, more here: http://www.zipp.com/...abid/60/Default.aspx), and feel that the increased ride harshness, reduced contact patch, increased rolling resistance and so on associated with narrower tires just can’t really be justified on either of these rims.
Now, if you are running an H3, old Zipp 440, Campy Bora or Reynolds wheel, then we have definitely seen advantages in the wind tunnel to running 18 or 19mm tires over 21 or 22mm tires, and I would strongly recommend them for those applications from a pure speed perspective, but with the newer Zipp rim profiles, I can honestly say use a 21mm at a slightly lower pressure, and save yourself the added harshness of the high tire pressure as well as gaining back some improved handling and still maximizing aero benefits. These latest generation wheels have been fully designed around 21-22mm tires, so you can be confident that you are not sacrificing any performance with them.
From Park Tool:
**
The tubular tire shape may not be a good match with the radius of a particular tubular rim. The tubular bond strength comes from the outer edges of the rim more than the center. If the tire is too small for the rim, there will not be good contact at the outer edges. In the cross section image below, there will be poor contact between tire and rim at the outer edges.
The mentioned tire fits OK but maybe 1 mm (or a bit less) wider would fit better.
Sergio
I have a Stinger 9 on order and Hed suggested the Vittoria Corsa CX 21mm. They also sell it in a 23mm wide tire…hmmm
IIRC, they recommended 22mm size tires for the Stinger 60/90. It used to be noted on their website before they updated it. You can always call / email and ask them. They are really good about that and I would expect a response very quickly.
So from another website:
http://www.trisports.com/hedst90fr.html
Looks like the 22mm is still in affect for the older Stingers 60/90 wheels.
From Park Tool:
**
The tubular tire shape may not be a good match with the radius of a particular tubular rim. The tubular bond strength comes from the outer edges of the rim more than the center. If the tire is too small for the rim, there will not be good contact at the outer edges. In the cross section image below, there will be poor contact between tire and rim at the outer edges.
The mentioned tire fits OK but maybe 1 mm (or a bit less) wider would fit better.
Sergio
Hmmm…so, does this imply that it’s not a good idea from a bonding standpoint to run a tubular tire width as narrow as the rim on these older rims? In other words, you can’t get the aero advantage of running a tire as narrow as the rim without compromising the bond strength?
I guess that’s one more reason to run clinchers, huh? 
Do you think Crr is more important than these differences between the clincher and tubular models? 
http://www.hedcycling.com/aerodynamics_technology/
Sergio
So from another website:
http://www.trisports.com/hedst90fr.html
Looks like the 22mm is still in affect for the older Stingers 60/90 wheels.
I got an e-mail from Andy at Hed and he confirmed to me that 22 mm is the best choice on the 69/90 Stingers.
Thanks to all for your comments.
Sergio
When I had Stingers a few years back, I used a 21mm on both 60’s and 90’s. The 21’s worked fine on the 60’s, but the sides would pull away on the 90’s when the tires were deflated. I ended up switching to a 23mm on the 90’s which worked great.
Do you think Crr is more important than these differences between the clincher and tubular models?
http://www.hedcycling.com/...dynamics_technology/
Sergio
In all honesty…there’s no way to judge the applicability of those differences shown on that site since there is absolutely NO detail about what tires where used with each wheel, or the conditions or protocol of the testing.
Your guess is as good as mine…
I wonder how much the “good” glueing procedure helps mitigate this. From what I’ve read the best procedure , from a rr standpoint, likely fills this gap pretty well.
Styrrell
I wonder how much the “good” glueing procedure helps mitigate this. From what I’ve read the best procedure , from a rr standpoint, likely fills this gap pretty well.
Styrrell
Dunno…but adhesive bond strength is usually best with the thinnest bond line that “fully wets” the 2 surfaces. Al’s multi-excess-coat gluing technique ensures the “fully wetted” part…but, I can’t think that intentionally increasing the thickness of the bond is going to be a good thing, either Crr-wise, or strength-wise…