All of Honda's 1988 model NX650 motorcycles are being voluntarily recalled to repair a defect that could cause loss of front-wheel braking, the company announced. American Honda Motor Co. Inc. said Tuesday that its dealers would replace front wheel hubs free of charge on all 2,032 of the motorcycles sold. This is the first year the model has been produced. Under severe use, one or more of the bolts securing the front brake disc assembly can loosen, the company said, posing a potential danger of front brake failure. The rear brakes are unaffected and Honda hasn't had any reports of accidents blamed on the defect, the company said. Owners of the bikes will be notified, or can take the machines back to their dealers.