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Looking for brake mounting bolt predrilled

6812 Views 24 Replies 11 Participants Last post by  petrole
Hi guys & vendors,

I am looking for brake mounting bolt predrilled for both brakes. Can someone tell me where to buy, or sell one? I can't find it in ebay. For racing.
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I get all my fasteners from Pro Bolt USA.

I'm addicted to titanium and carbon fiber.
Google: 'wire lockable metric bolts' and I think you'll find several vendors. Also, aircraft parts or milspec parts vendors will have them - they'e out there if you do a bit of legwork.
Or just buy some 1/16" or 3/32" drill bits and make your own.
im in australia so the shops are different. will try to find those aircraft, or do you know the specs of oil bolt and both brake bolts?

i'm going to drill i think, can the torx bolt for the brake be drilled? it is concave model.
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.

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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.
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.
Can you post photo of the wire line, where to tie it to? Is stock bolt really that hard? Yamaha said to just drill it.
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.
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.
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.

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.
Just finished drilling 2 brake bolts. Just knew drill bit can go dull. Cost me 5 drill bits.
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.
i just kept going on. was tempted to start a new hole.
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.
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I think having the hole can increase bike value, it is for safety anyway.
I think having the hole can increase bike value, it is for safety anyway.
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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They tell you to look out for that sort of thing in second hand bike guides and give them a wide berth unless the price is right.
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But then, bikes are revved. Hard to see if engine is in good condition. However i like seeing my lockwire. Recommend to wire oil bolt, brake bolts.
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