Looking for brake mounting bolt predrilled
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The factory bolts are "button head socket cap screws" - really hard if not near impossible to drill. Remove them, take them to your local hardware-type place and buy a couple "socket head cap screws" same size/thread/length.
Try to get the exact length if you can or go a bit longer and grind/cut them to length. Too long and bolts will hit brake rotor. Too short and your brake caliper may fall off. A little long is preferable to too short. Don't remember exactly what they are, probably M8 or M10. Get a couple of nuts too. Thread the nuts on your bolt (tightly) and use them to clamp the bolt in a vice or vice-grips so the bolt doesn't try to rotate while you're drilling it. Drill the bolt head so that the hole goes through the socket flats. Clean up the burrs in the socket so you can get your wrench in there later. If you need to shorten the bolts, thread a nut on first - it'll help clean up the threads after. You may go through a couple of bits and bolts before you get two good ones. You end up with something like this:
Safety wire bolts are common in the aircraft industry, so you can sometimes find them under 'aircraft parts' or 'aircraft fasteners', but for me it was just easier to make my own. Don't forget Loctite.
Try to get the exact length if you can or go a bit longer and grind/cut them to length. Too long and bolts will hit brake rotor. Too short and your brake caliper may fall off. A little long is preferable to too short. Don't remember exactly what they are, probably M8 or M10. Get a couple of nuts too. Thread the nuts on your bolt (tightly) and use them to clamp the bolt in a vice or vice-grips so the bolt doesn't try to rotate while you're drilling it. Drill the bolt head so that the hole goes through the socket flats. Clean up the burrs in the socket so you can get your wrench in there later. If you need to shorten the bolts, thread a nut on first - it'll help clean up the threads after. You may go through a couple of bits and bolts before you get two good ones. You end up with something like this:
Safety wire bolts are common in the aircraft industry, so you can sometimes find them under 'aircraft parts' or 'aircraft fasteners', but for me it was just easier to make my own. Don't forget Loctite.
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I was going to mention loctite after you said they may be a bit short. Then I realized that with safety wire, wouldn't it be impossible to actually rotate them loose if done properly? Loctite definitely wouldn't hurt but with safety wire properly done you may not even need it.
Edit: if you have access to a proper stil press with a vise, it's very easy. I drilled oem R6 caliper bolts at work with no problems.
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The plate the bolts thread into is not very thick and the bolts were just long enough to end up flush with back side (toward rotor) of the plate. If you go much shorter than stockers, I'd be concerned about not enough thread when you torque it - resulting in stripping it out - you only get two or three threads of purchase as it is, so....safety wire AND Loctite was my call.
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Remove one of the rotor mount bolts and look at it - because it's a button head:
http://www.mcmaster.com/#97763a362/=11ide38 , it will be much more difficult to drill than this:
http://www.mcmaster.com/#90152a342/=11idby4
Safety wire routing shown in photo posted - I used a drilled banjo bolt to 'tie it off'. There's a ton of on-line resources for 'how to' safety wire. Not much else I can offer. Good luck.
http://www.mcmaster.com/#97763a362/=11ide38 , it will be much more difficult to drill than this:
http://www.mcmaster.com/#90152a342/=11idby4
Safety wire routing shown in photo posted - I used a drilled banjo bolt to 'tie it off'. There's a ton of on-line resources for 'how to' safety wire. Not much else I can offer. Good luck.
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Oh yea it looks clearer now. Cant the wire link only betweeen the 2 mounting bolts? Is it enough for the wiring standard? My bike is stock and never had experience loose bolt in stock. I hope they lighten up the requirement.
I am going to the Australia R3 cup btw.
I am going to the Australia R3 cup btw.
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Refer to the applicable tech rules for your race organization. You may also need to safety wire radiator cap, oil filler and drain plugs (predrilled ones readily available - see oil drain plug thread), oil filter, water pump drain screw, axle nuts, etc. My current race rules do not require securing banjo bolts, but I still do it anyway.
You may want to track down Aufitt - he would know what's required for R3 cup rules.
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If you break or burn up a bit part way through, you may be better off starting with a new bolt or at least abandoning that hole - chances are, you'll immediately burn up another bit if you keep trying to drill the hole you just burned up a bit in. Get the cobalt bits - usually good for about twice as many holes as HSS.
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Probolt
https://www.probolt-australia.com/
Costs a Kidney and a Testicle, but as said the button heads are hard to drill. (Even though Im a Mech fitter and can do it)
Saves the originals for when you sell the bike stock, and can use the Probolts on the next build.
https://www.probolt-australia.com/
Costs a Kidney and a Testicle, but as said the button heads are hard to drill. (Even though Im a Mech fitter and can do it)
Saves the originals for when you sell the bike stock, and can use the Probolts on the next build.
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It can work against you as well. People who see safety wire will typically think " Oh safety wire, it was probably a track or race bike" and those bikes, at least in California, seem to fetch less money than just a regular old street bike.
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