A poster on wattage was doing a workout on his rollers riding a set of Zipps with Tufo S3’s. He noticed his wattage was way high for his speed. He put his campy clinchers on and lo and behold 80 less watts to ride the same speed.
Another posters asked, are you using tufo tape instead of glue? The answer was yes.
Take home lesson, if you ride tubulars you better work on you gluing technique.
greg
And I still will:).
While it may well be that the tape adds rolling resistance, I have to believe that there is more going on here than just the tape.
By and large, sew ups have more ‘hop’ than clinchers. I’ve got to believe that this adds significant rolling resistance, especially in a controlled environment such as rollers, where rolling resistance is isolated as the largest single resistance factor, and you are riding on a perfectly smooth, round cylinder. In fact, riding on a round cylinder likely exaggerates the rolling resistance. If it weren’t for the varying aerodynamic contribution of the spokes (you’d need to compare wheels with the same number of spokes and spoke shape) the rollers would be a great way to do home tests of rolling resistance.
My clincher Ksyriums with Vittoria CXs mounted have no more than .010” hop, I haven’t bothered to remove the tires to get an accurate measurement of the rim, but the rims have very little hop. My recently acquired sew up race wheels (Zipp 404 front, Hed 3D rear) are a different story. Without tires, the front wheel has about .015” of hop and the rear wheel about .010” of hop. With Tufo S3 Lite 215 tires mounted, both have about .040” of hop. (I’m measuring with a set of machinists calipers, to really do this right you need a dial indicator.) This is a substantial difference from the clinchers. And the Tufos actually have less hop than lots of other sew ups. I’ve only had them out on the road once, but to be honest they didn’t seem nearly as fast as I expected, I’ll need to do further testing before I draw any firm conclusions. Tires were glued on traditionally. Frankly, the only reason I got sew ups was because of the killer deal I got. I hope I didn’t make a mistake.
I’d be curious to know how much hop other folks are experiencing in their sew up wheels. (Of course, to know how much of the hop is from the tire you would also need to measure the wheel, which is very difficult to do with the tire mounted, but if there is a lot of hop it shouldn’t be too hard to tell if most of the hop is from the tire, not the wheel.)
Wouldn’t the take home lesson be that you should work on your taping technique?
How was the rider measuring wattage? SRM I assume?
Here’s a link to the thread on wattage so anyone who is interested can follow it there.
http://lists.topica.com/lists/wattage/read/message.html?mid=911893169&sort=d&start=33849
Yes, you may be correct about the taping but it seems like there would be an inherent give in the tape that may increase rolling resistance that you would not have with glue.
greg
greg
I don’t get what you are trying to saw Yawg.
Explain. Thanks!
Don
The tape increases rolling resistance. Use glue instead if you use tubulars.
no offense but it seems like you are drawing an invalid conclusion from a test
The test was between products A and B (tufo tape vs clinchers) but then you draw a conclusion between A and C (tufo tape vs glue).
Also there were so many different variables between the tests (tire type, tire pressure, wheel type and trueness, age/wear of tire, calibration of power meter) Plus I’m not a firm believer of drawing conclusions from a single isolated incident/test…
Maybe Im missing something but it seems to me that it is a little premature to make such claims…
Thinking a little bit more about this, it could be caused by a number of factors that have nothing to do with gluing vs. taping, such as tire pressure, tire tread, hubs, et cetera. I think singling out Tufo tape as the offending variable is quite a stretch in this case.
Now if the rider produced the same 80 watt difference with two sets of Zipps with Tufo S3s - one taped and the other glued - then we’d have something scientifically interesting to talk about.
Haha. We’re on the same wavelength.
now I am really up in arms. i just built a PT Sl (some problems with those) onto 404 rims (tubular), with S3’s and tape. I need to get these on a bike and ride them asap!
Kurt
Oh, you used tape? Don’t expect to ever go faster than 15 mph on those wheels 
yeah you dont want them anymore they’ll only slow you down
Tell you what…I’ll give you 20 bucks for them 
.
yea, you guys are right. I just tossed those pos’s into the dumpster out back.
Kurt
DAMN…thats alot of watts, due to just the glueing/taping method. I find that very difficult to believe.
I’ve been using Tufo tape for over 2 years. It works great!! I love it…although I really had no problems with the glue either.
I’ll start an auction on your wheels with the tape…I’ll give you $$20.50 but you’ll need to pay shipping since the wheels aren’t worth much with all that junky tape on them.
Ok… so this guy is cruising along on his rollers putting out say 250 watts at an indicated speed of maybe 25 mph. (just guessing because I don’t have anyway to measure watts on my rollers) He thinks that this is out of whack so he changes wheels and now he is using only 170 watts at an indicated 25 mph. So the tufo tape somehow eats up an astonishing 32% of his power output. To put it another way at 250 watts 32% of his effort is being lost into the tape. If this were true the tape would be getting damn HOT from dissipating all this energy. I have a set of Reynolds (low profile carbon rims) with Tufos taped on them. If they were eating up 32% of my power then my times on all of my training routes would be all messed up and that is just not the case.
Just because he is using 80 more watts on the rollers doesn’t mean that he will use 80 more watts on the road. Remember, rollers isolate rolling resistance as the main resistance factor. On the road, rolling resistance is a vastly smaller component of overall resistance compared with air or gravity. I also would speculate that the small diameter of the roller would exaggerate rolling resistance. OTOH, that doesn’t mean that the test isn’t revealing a cause for concern with the rolling resistance of his tires that bears further investigation. Even if that 80 watts on the rollers only translates to, say, 8-16 watts on the road that would be of significance.
yea, the rollers will exaggerate the power loss for sure. I just talked to John Verhuel and he recommends the “hardest” glue you can find, this will help stop deflection on the rim.
Kurt
Hello All,
I am the guy that got this all started with my ride last night.
I am testing more wheels today and will do so on the road as well, It could be tape or the tires. It also happens on the trainer.
did anyone ever consider that tire pressure or the surface of the tire wasn’t the same. Wow. you guys must be like english majors or something.