you need to put on some weight Bob. I recommend multiple sets of full squats, 20 reps, 3X weekly. Lots of protein powder, shakes ... ice cream if need be.

Cadence is easy. Force is hard :-)

Maybe you should buy a new disc ;-)

I think the zipp disc I have is quite stiff actually I'm suprised it doesn't flex more. But as said I don't think sub9 and 900 model differs in flexibility.

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http://www.nasvik.se

hey guys how bad is the sub 9 rubbing on the cercelo's I just purchased an 08 pc3 and sub9. Also are the adjustment screws on the cervelos on the back were the skewers go are they supposed to be out the same length and how far in or out is everyone running on the bikes. I put the wheel on and yes its close to rubbing the frame about quarter in. I hope I can use this frame and wheel combo.

Yeah. -And sell my Sub9 to... you? ;-)
Having ridden both the 900 (tubular) and the Sub9 I get the impression that they are equally flexible. There's just less room with the Sub9

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I'm racing tomorrow morning, so I just went out and set up the bike with the race wheels for the first time since this thread began. I've raced a number of times now with the P3C/Sub-9 and have not given frame clearance a moment of consideration before. Last week I shattered the best 40k TT time I've ever done by minutes with this combo (though I must give a major nod to the fantastic course I got to race, too).

Looking at the clearance just now I'm guesstimating about 2 to 3 mm of clearance on each side between the bulge of the wheel and the chainstay. It looks like plenty to me. I'd bet that if the wheel is going to flex and rub anywhere, it's only going to be under very heavy torque on an out-of-saddle effort and it's going to rub at the brakes before it rubs at the chainstay area.

I've got a pretty strong TT start and I don't recall hearing the rear wheel rub. Neither my wheel nor my chainstays show any signs of rubbing. I'm only about 150 pounds, though. Maybe that's a key factor.

As for messing up the decals, what decals? You don't need them. Why put decals over a dimpled wheel? Completely and utterly pointless except for advertising for Zipp ... and for what the wheel cost, they can pay me if they want me to advertise for them!

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Bob C.

The "science" on any matter can never be settled until every possible variable is taken into account.

I took mine out for it's first ride yesterday, it took some work to get it on my p3c. I had to ride with the break lever open and the adjustment all the way down even after I loosened the cable. I don't have a problem with chain rub, but had to change my limiter screws and shift points. Then the flex hit as soon as I stood up. I could hear the disc rubbing from one side of the break pads to the other. I'm pretty disappointed in the sub 9.

This is also my second sub 9. the first was defective and had a few dents in it and zipp told me not to ride it. I had to wait 3 months to get another.

Yes I would love to no how far to set the screws on the rear frame of the pc3. Mine are not set to equal distance are they suppose to be please help

make sure that the wheel is even on both sides. If one screw is recessed more than the other the wheel will wobble and not run straight.
It's also a good idea to get the tire close to the frame without having it rub.

It is rubbing bad enough that I have rubbed some of the paint off on one side.

As for the adjustment screws; I don't think that it is important that they are even, which is what I was doing to begin with - looking at the screws, not the wheel, but it is apparently important that the wheel is even. Just as a note, I had to put loctite on them to keep them from moving. By the end of my first two rides the wheel had moved itself forward so that it was rubbing against the seat down tube.

I'm not 100% certain, but I think that officially there needs to be 3mm of clearance between the tire and the frame - you should be able to slide a credit card in there or something like that.

Thanks for the info thats what I thought I just have never owned a bike with a rear triangle like that. I hope my sub 9 doesn't rub when I ride it. I do see that I am going to have shave the brake pads. I would love to hear from more cervelo and sub 9 owners what they think about the combo

I haven't done anything to the rear brakes except open them up as much as possible. I am using Campy Record.

Nothing done to the brakes. I Experience no rubbing against the brakes, only the chainstays.

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The average human uses 10% of his brain power.

Find nine other people

Yet to ride the sub 9 does anyone on here feel that the sub 9 is better than just the regular zipp disc. The reason I ask is I may sell my sub 9 since I am yet to ride it and get a regular disc. Thanks love to hear people's comment. THe combo looks fast as shit.

No Sub 9 for CSC - http://forum.slowtwitch.com/...McGees_P3C_P1788741/

And I am about your weight and mine rubbed on the chainstays when I got out of the saddle . . . but I only tried it for one short ride as I did not want to damage the disc or the bike.

First race on my sub 9 disc. I was a minute slower than were I was last year using a corima on the same course. And 30 seconds slower than a race 2 weeks earlier using my corima. When I got out of the saddle for my sprint I could feel and hear the disc rub on the break pads (or chain stay). I'm pretty sure it was the pads.
So far I'm not happy with the purchase. Maybe the sub 9 is slower than the other disc when it's on the bike and not tested by itself? Maybe Zipp screw up and made a flimsy product. It wouldn't be the first time they made poor products, does anyone remember all of the hub problems they had in wheels in '02-04 (give or take a year)?

I asked a guy I know with a Sub9 who is not exactly small and is able to push on the pedals REALLY hard...his nickname rhymes with "uber" ;-)

He said he hasn't noticed any flexing whatsoever. Take that FWIW.

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I don't know if it's any more flexible, but I suspect it's wider at the rim, which is probably the issue. The clincher disc is based on a 404 clincher rim, which is only 22 or so? The 808 tubular rim (on which the sub 9 is based, or so I think) is pretty darned wide, 27mm or so--so I'm guessing that's why it doesn't play well with certain frames.

I am running a P2C with a sub 9 (upgraded from 900 Disk in Jan) and I have had very bad rubbing on the chain stays...

Cervelos stock dropout limiter screws are normally quite loose and never stay where they are supposed to (This said they are not designed to be load bearing you have to make sure your rear skewer is nice and tight as it is meant to hold the wheel in place) however a good application of teflon tape and they firm up.

I have tried to adjust the rub out of the Sub 9 and I just cant manage it. Under load it rubs. I am 6"4' and 190 pounds but that should not matter..... I have had no rubbing problems with my rear 808...

My bike is cosmetically damaged and I have had to remove the stickers from the Sub 9..... Not real happy....

Josh@Zipp..... anybody at Zipp..... anything to say???

IMO the 900 is stiffer but the Sub9 downhill with a slight tailwind is awesome.....

There is the brake track width, and then the rim width at the widest point, made it a challenge to select an appropriate tire, I went with a 21mm Vittoria vs a 23mm because the brake track measures 21mm and the tire and brake track are the same width

I had to change brake pads to get my 1080 from rim to fit my Hooker brake

I haven't read through the other responses to this thread yet but I am using a sub 9 rear on a P3C with SRAM Red. I just raced it at St. Croix 70.3 and had no rubbing issues even on a hilly course when I was using the crossover gear several times.

Be sure your dropout screws are adjusted correctly. Remember, one benefit of a sub-9 is runnning the disk as close to the frame as is possible for optimal aerodynamics.

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Tom Demerly
The Tri Shop.com

I wonder if there is a link to rider/frame size/Running Gear....

I am on a 61cm P2C 6'4" and 190 pounds on DA 180mm cranks...

What are the others with rubbing problems stats???

I have emailed Zipp and am awaiting a response...

51 cm P2C
5'10" and 155lbs
172.5mm Zipp Vuma Quad Cranks

I guess that puts me at the other end of the spectrum

I'm in the same boat - New P3C and Sub 9 and now i am wondering if this was a wise combo :( My first race is Sunday so I will be spending Friday on a shakedown run to see if it rubs.

I received an internal email from the zipp email system about this yesterday regarding the rubbing on a cervelo...this is the first major complaint we have had on a cervelo frame that I'm aware of. We know that both the Giant Trinity Alliance and Scott Plasma just don't have enough room to reasonably run the sub9 and we are working with both companies to ensure adequate clearance in the future.

As for the wheel rubbing any frame, there are 2 primary factors at play: clearance and frame stiffness. The way a wheel is loaded during out of the saddle efforts is such that the primary axis of bending runs very near parallel with the chainstays, this is why some wheels will hit the brake pads or seatstays during hard effort, the wheel is bending about the fore-aft axis of the bike, and shows very little deflection at all near the chainstays. The bike, however, is deflecting almost entirely in this plane, which is why chainstays seem to be so wide these days as they attempt to counteract this force. We worked with Cervelo and other companies during the nearly 14 month development of the sub9 and 1080 wheels (which are nearly identical out near the tire bed), and were confident going into production that we would not have issues, and other than the 2 frames mentioned above we know of no outstanding fitment problems in any frame thus far. We also attempted more than 30 layups to tune the stiffness/ride quality relationship of the wheel and found very little difference in deflection of the wheel as measured at the chainstays with increasing wheel stiffness...in fact doubling the lateral stiffness of the wheel reduced deflection in the chainstay plane by less than 10%...

Ultimately I ask that you call our customer service line and we will see what we can do to solve this incompatibility and your unhappiness with the product. Unfortunately, even if we could build customer super stiff special discs, the problem will not be alleviated. The only other option from the wheel side would be to make the wheel narrower, but that defeats the 80 hours wind tunnel time... Please call our customer service line at 1.800.472.3972 or contact your local shop where the wheel was purchased and we will try to find the best solution
Regards

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Josh,

Thanks for taking the time to respond. There seems to be a few of us that are expeiencing rubbing on P2Cs and P3Cs.

I am the one that logged the question on the Zipp email system.... I would call but I live in Australia so cant access your 1800 number.....

I will work with the Zipp team offline to try and resolve the issue (Disk was purchased from Competitive in the USA)

Thanks

OZJester