For dirt/jumping, there are three-piece cranks and there are Profile three-piece cranks. Since 1979, Profiles have been the benchmark products in this hard-fought category. The arms are made from tapered 4130 chromoly steel, the 48- spline axles are 4140 chromoly, and the washers and bolts are all aircraft grade alloy or chromoly.
Everything is made in the USA, and the high quality construction is reflected in the way it all fits together with Swiss watch precision, the arms sliding accurately on to the axle splines.
A wide range of arm lengths, from 140 to a gargantuan 190mm, is available, and fitting chainrings and chain guides is as easy as sliding them on to the axle and doing up two bolts. Because the Profiles are made from tubular steel they’re rock solid and good for harder hitting riders who break conventional aluminium alloy cranks. Needless to say, our test ones never budged an inch. We’ve used these cranks on dirt jump bikes and downhill rigs without any problems other than occasionally catching the insides of our ankles on the arms. If you’ve got the money, one of the best ways to make your bike more durable is to fit Profile cranks.