R CLIP / SPLIT PIN

 

An R-clip, also known as an R-pin, R-key, hairpin cotter pin, hairpin cotter, bridge pin, hitch pin or spring cotter pin, is a fastener made of a springy material, commonly hardened metal wire, resembling the shape of the letter "R". Hence the name “R-Clip”!!!

 

R-clips are commonly used to secure the ends of round shafts such as axles and clevis pins and are completely reusable.  In terms of racing they are often found when using “tire wire” to secure front axle bolts, engine oil filler plugs, etc…

 

The straight leg of the R-clip is pushed into a hole near one end of the shaft until the semicircular "belly" in the middle of the other, bent leg of the R-clip grips one side of the shaft resisting any force removing the R-clip from its hole.  To assist insertion the end of the bent leg is angled away from the straight leg.  This angled end rides the side of the shaft and opens the "belly" mouth enough to pass the widest part of the shaft as the R-clip is inserted.