Joined: Mar 2007
Posts: 3,908
Likes: 320
From: Greer, SC
Bikes: Holdsworth custom, Macario Pro, Ciocc San Cristobal, Viner Nemo, Cyfac Le Mythique, Giant TCR, Tommasso Mondial, Cyfac Etoile
Maybe the instantaneous reading is +/-15% but the error integrated over some distance would be much less - worth looking into.