Safety Wiring Techniques
Safety wiring is not mysterious or difficult. It really only takes some time and practice, and will soon become second-nature for you at the track. Safety wiring should always be done to keep bolts or nuts from backing out. That means always wire in the direction that will tighten the bolt. Safety wiring is also done to prevent any part that does come loose from falling onto the track and causing damage to another bike or rider. It never hurts to safety wire any critical part of your bike, such as controls, beyond the requirements in the rulebook.
Now that you know what you need to safety wire, you're probably wondering how to do it. First, go out and get the following items:
Safety wire pliers. Just buy a pair just like the ones in the picture. These are available at larger bike shops, racing supply companies, and even Wakula Racing. Some people might suggest that you can use a "twirl tool" or a pair of needle-nose pliers, but you will be much happier with a pair of real safety wire pliers. Borrow a pair if you must.
A can of stainless steel safety wire. Some racers use ½ to a full pound can per season. The best overall size to buy is .032" diameter, although having a can of .028" and some .050" can be handy for tight spaces or damage repair. Safety wire is available at most motorcycle shops.
A variable speed drill and a dozen 1/16" drill bits. If you have access to a drill press, that can make the job faster. The tiny drill bits will only last 4 to 6 bolts. They will break often, even if you're careful, and dull quickly. Pick up a few 3/32" bits also. Be sure to keep the bit lubricated while drilling.
How to drill
Except for a few places on your bike where bolts are already drilled for a cotter pin, the nuts and bolts on your bike will have to be drilled before they can be wired. There are various ways to do this. It is best to use a drill press and a small vice to hold the fastener or part. Whether you have a press or a hand drill, here are some tips. First, go easy with those little drill bits. It takes very little force to break one. Lubricate the drill bit periodically with light oil. This helps it cut faster and also cools the bit. When the bit is about to clear the far side of the item you need to be careful that you don't snap the bit. Many nuts and bolts are surface hardened and that last section takes the longest. Throw out a drill bit when it gets dull.
Most bolts can be drilled straight through the hexagonal head, as in the first figure. Drill from flat to flat, and keep the hole centered. For the studs of some mounting bolts where a portion of the threads protrude, you might opt to drill through the shaft and wire in the fashion of the cotter pin found in most rear axles. If you do this, put a nut on the bolt first so that you can clean up the threads by taking the nut off. Banjo bolts (used on brake and oil lines) are hollow and cannot be drilled straight through. These must be corner drilled, as shown in the next figure.
Hexagonal nuts are drilled across one of the corners. This is a three step process. The drawing shows the drill bit pointed at the flat of the nut. Drill straight in until the bit is in about 1/16 inch. Then turn the nut in the vice about 15 degrees. Continue drilling until the bit is in about 1/8 inch. Finally, turn the piece again so that you can drill all the way through the corner.
Allen head bolts may be drilled through either one or both sides. Be sure to drill though the flats of the allen or you will weaken the grip offered the allen wrench. Drilling through both sides will make wiring the bolt easier.
How to wire
Once you have the nuts and bolts drilled and reinstalled, you need to wire them in place. You should first ensure that everything is torqued properly. Over-torquing a fastener will weaken the threads, and repeated over-torquing can lead to failure. Your bike's manual will have the torque and thread treatment specifications for each fastener. If appropriate, loctite or lubricate the threads first. You then need to wire the item as an insurance procedure.
When wiring nuts or bolts, there are several techniques used. The first is to wire the nut or bolt to a convenient fixed object, such as the frame or a fork tube. Another common technique is to wire two or more fasteners together so that none of the fasteners can back off. A third approach is to wire the head of a bolt to the nut on the other end. The figures show the first two of these techniques. Most drain or fill plugs will be wired to a frame member or engine part. Brake caliper nuts and bolts are usually wired together. Fork pinch bolts can be wired together or to a fixed item. A muffler mounting bolt is usually wired to its own nut.
The figure on the left shows a nut wired to a fixed member. It is best to start by looping the wire around the member and twisting the wire together. Continue twisting until the twisted part reaches just short of the nut or bolt. Thread one piece of the wire through the hole on the nut or bolt. Pull the wire tight and then continue twisting the wires together. Leave about 1/2 inch of twisted wire and cut off the rest. Throw the ends in the garbage can immediately. Tuck the end around so that you can't cut yourself on it. Tension should be kept on the nut or bolt in the tightening direction. The diagrams here show the wire in a loose fashion so that you can see the idea. Your completed wiring should be neat and tight.
Always discard your excess wire in a trash can. Those little pieces of wire can flatten a tire in no time. Always use caution when working with safety wire. The ends are very sharp and can easily cut your fingers. When you have finished wiring a nut or bolt, bend the end of the wire so that it doesn't protrude and create a hazard.
This figure shows two nuts wired together. The procedure is similar to wiring to a fixed object. Loop the wire through the hole of one of the nuts (or bolts). Twist the wire and maintain tension on the wire in the tightening direction of the nut. Continue twisting until the twisted wire reaches just short of the hole for the second nut and wire that nut. The wire should pass between the nuts to maintain tension on both nuts when the job is done. This process may be continued to wire additional nuts in succession, such as an oil filter cover, sprocket nuts, or water pump.
If your bike has a spin-on type oil filter, it can be wired in place by placing a hose clamp around the filter, then running a piece of safety wire from the clamp to the frame or another fixed object.
Another area which requires special techniques is fuel and water lines. You can use the spring loaded clips that come stock on most bikes, or use small hose clamps. If you use safety wire, be careful because you can cut through the hose by using too much tension. Small zip ties will also work.
Water lines are usually clamped with standard hose clamps. One precaution you can take is to thread same safety wire through the slot on the screw of the clamp, then attach the wire to the clamp. This will keep the hose clamp from loosening.