Shimano has found that there is a greater likelihood of a puncture in DURA-ACE clincher tyre wheels WH-7850-C24-CL and WH-7850-C50-CL. This is due to the surface texture of the rim in combination with the use of spoke-hole plugs.
The phenomenon can be very easily eliminated by replacing the spoke-hole plugs with genuine 18 mm high pressure Shimano rim tape.
At the website http://cycle.shimano-eu.com an instruction can be found about replacing the spoke-hole plugs by rim tape.
All Shimano clincher wheel sets will be delivered with Shimano
rim tape as of now. Dealers are instructed to supply Shimano rim tape free of charge to consumers affected by the problem, for which a refund will be available from Madison who have been sent replacement stock.