Hello dear wheel experts
I just built me a set of Powertap hubs on a set of NOS Colnago Carbon Rims.
Hubs and Rims are 28holes, Build is made full with DT Competitions and Sapim allow internal inverted nipples. Radia Front, 2 cross rear
The set is now built and I just went for a short ride on still not glued tubulars, to let the spokes set in, so I can do a last truing before gluing the tubies.
Problem is the spokes rub on the derailer on the small chainring/largest cog combination. It only rubs when I am sitting on it and climbing a steeper hill, If I dismount and roll the wheel there is no rub.
Off course it is due to more tension and hence flex on the spokes on that particular combination. that is clear to me, however I have built many other wheels and I never experienced rub.
The wheels are not fully centered, but they are setup exactly as my set of Boras that are slightly off center ( very little though ) from the factory.
So I would like your opinions on what to do, I thought on several options
1. rebuild the rear drive side with all heads out to minimize the offset of spokes on that side.
2. tension more the wheel so they flex less ( not so fond of this one )
3. put a thin spacer on the cassette and setup the derailer a bit more outside.
4. recenter the wheel more to the NDS to give more space to the derailer.
maybe you have other ideas or some recommendations, the wheel spokes are build with "lowish" tension, but I don't really know because I don't have a tension meter, I have always built my wheels ( more than a dozen ) on feel and never had this problem before....
here some pictures of the wheels and details to help on the diagnose
thanks so muchColnago Powertap
, en FlickrOn new Wheels
, en FlickrPowertap Detail
, en FlickrDSC04716.jpg
, en FlickrDSC04717.jpg
, en FlickrDSC04720.jpg
, en Flickr