Zipp 404 hitting brake pads.

shaunbear said:

I'm not sure if this is normal but i just purchased the Zipp 404 which i love but every time i get out of the saddle and peddle hard the rim walls hit the brake pads. The distance from the pad to the rim are normal and actually the same distance as my other rims when its all set up. I spoke with Zipp and they told me to adjust the preload which i did but either im not doing it correctly or that is just not the problem. I love the wheels and its a shame i cant use them in races since i have this problem until i fix it. Any suggestions are welcomed and since this is my first post on this forum i glad to be here and love all the info i have read for some time now.

First, as it happens, I'm a certified Zipp Independent and Unaffiliated Wheel Tester, so you're best bet is to ship those wheels immediately to me.

........or not. How much do you weigh? From a the point of view of specs, the Zipp 404's should be pretty laterally stiff because of the tall rim; however, that doesn't mean they came out of the factory with even spoke tensions or maximized spoke tensions. It'd be worth having someone check the spoke tension to see how it compares to max and to see if it can be increased at all.

To be clear, you did increase the bearing pre-load, right? Your QR isn't slipping in the rear, is it?
What kind of frame are you using?

Well i spoke with the shop i purchased them from and they said the same thing which i guess i'll bring it to them to check since i just purchased them. As for the frame and QR, I'm using a litespeed vortex frame and the QR didnt slip at all. I weight 160lbs. I doesn't make sense to me that it should be hitting the rim since i only used the rim a few times, how would the tension of the spokes have loosened up so quickly?

shaunbear said:

Well i spoke with the shop i purchased them from and they said the same thing which i guess i'll bring it to them to check since i just purchased them. As for the frame and QR, I'm using a litespeed vortex frame and the QR didnt slip at all. I weight 160lbs. I doesn't make sense to me that it should be hitting the rim since i only used the rim a few times, how would the tension of the spokes have loosened up so quickly?

It's possible that the wheel wasn't tensioned properly in the beginning. It's also possible that they didn't stress relieve the spokes. The spokes may not have even tension. All of those things could lead to spokes loosening or to excessive lateral movement in the rim.