Really basic / naïve disc weel question

MattAaronson

So I bought a disc wheel off of ebay, a Zipp clincher.

I had the bike shop set it up with rim tape, a tube and my Vittoria Open Corsa tire.

Two totally basic questions:

1. The bike shop put a wheel magnet on the disc - they used a quarq cadence magnet and the quarq putty to sick it on. Is this normal? Doesn't look too aero to me. I have a Garmin Edge 500 with GSC-10, so I assume it is only using the GPS for speed anyway. Thoughts on removing it??

2. The wheel has a cutout where you can see the valve of the tube, and where you use the "crack pipe" adapter to fill the tire. The cutout doesn't look too aero either...do people cover this up with a cover or electrical tape, etc?

Thanks much, Matt.

 

Cary Blanco

1) If you don't need the speed magnet on the wheel, feel free to lose it. I don't think it's going to make a lot of aero difference either way. There are magnetic stickers out there, I don't have one so I can't comment on their effectiveness.

2) Wheelbuilder wheelcovers come with a "cover" for the "valve hole", it's basically a sticker like your bike race number sticker in the shape of the valve hole. You can try electrical tape of see if you can find some black sticker material and cut it down to size. I forgot to put the sticker cover on at eagleman and IMLP last year, not sure what I gave up without it on.

Cary Blanco

Also, I was also assuming you've got a crank based PM (Quarq or SRM), which means that you probably don't need the GSC-10 for cadence and if you're not using it for speed either, it can probably go.

kevhill

I got a roll of wide black thread tape for the valve hole, is just the right width and sticks pretty well (also easy to rip if forget the scissors). Just be careful of the braking surface, you don't want the tape on there...

mattsull

I use packing tape.

Chris G

i dont bother or care enough, if I ever lose by a tenth of a second I will know that I should have run a little faster or actually learned to swom

MattAaronson

Thanks everyone. Sounds like covering the hole is typical.

@ Cary - I do have a quarq PM...actually I've wondered if the GSC-10 is necessary, i.e. I never knew for sure if the quarq cadence was read only by quarq for power calcs or if it actually transmits that to the Edge 500 which would then use it in lieu of the GSC-10 data it receives. Also I've always wondered if it uses the wheel magnet info or if it is 100% GPS. I know my Forerunner only uses GPS and ignores the footpod even when the GPS signal is lost, but thought the Edge 500 operated a little differently.

Cary Blanco

I think if you've got the Quarq Cadence Magnet next to your bb it should be transmitting that cadence to the Edge. (I could be wrong on that). Turn off the GSC-10 on the edge and give it a try on your next ride.

mancona

Hey Matt, a few thoughts...

- As you pointed out the cadence/speed sensor is not needed with a quarq. The gps gives you speed and the quarq gives you cadence.
- With a zipp 900 clincher you do not need rim tape. I confirmed that with zipp and ran mine over a rear with out it. Rim tape is to cover spoke holes... the disc doesn't have any
- It may not look pro, but i think the blue painters tape works the best for covering the valve hole as it is really easy to remove but also stays on during a race. I put a nice Zipp sticker on the drive side (for pictures, etc) when I got it and never took it off. I cover/uncover the nds at every race with the tape.

MattAaronson

Cool, I guess I'll ditch the GSC-10 on my next ride and see what happens.

As for rim tape, truthfully I didn't pay much attention to what the LBS did, perhaps they did not put it on...I gave them the wheel and the tire and asked them to set it up, and they charged me $20 including the tube. I assumed it required rim tape or I would have done it myself...crap - another $20 to the triathlon powers!!!