broken brake caliper bolt

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FatNakedGuy

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well damn.. caliper bolt just snapped while using a torque wrench at 29lbs. The other three went in fine. Snapped in two where the two caliper pieces joint, and was able to remove the caliper

I searched the threads here and found people saying to use an easy out? what is that, and what brand/where to buy?

thanks!

p.s.

why are the brake bolts hollow?

<a href="https://imgur.com/2iVFyts"><img src="https://i.imgur.com/2iVFyts.jpg" title="Hosted by imgur.com" /></a>

 
Just one example, there are dozens:

https://www.amazon.com/Easy-Out-Screw-Extractor-Set/dp/B0002SDAIY

You drill the broken end, then screw the tool in "backwards" ... They work well if you do the first bit carefully.

I imagine the bolts are hollow to reduce un-sprung weight ... If they are broken at a "hollow" part, you might need to carefully select your extractor, and there would be no need to drill

 
...I imagine the bolts are hollow to reduce un-sprung weight ...
EZ Outs do work. They are hardened metal that is reversed threaded, the act of screwing in backwards (should) unthread the bolt. Be VERY careful, if you snap the hardened metal you will be looking for a machine shop for recovery.

Perhaps the bolts are hollow to help shed heat from the brake parts.

 
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As one who broke an easy-out and had to drill it out, by hand. You DO NOT want that to happen.

 
Looking at the picture, there sure seems to be a LOT of corrosion in the threads, or maybe a previous mechanic wrapped the threads with teflon tape (?)

Forget what I wrote...I thought I was looking at (in the smaller version of the picture) white corrosion around the threads. Now, looking at the original sized pic, I realize I'm seeing reflection of the flash off the visible threads.

Regardless, if it were me, I'd soak the threads voluminously with somethng like "Blaster" to dissolve/loosen ANY corrosion before I'd go after it with an EZ-OUT.

2iVFyts.jpg


 
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No Howie, that's Yamaha's bullshit thread locker that is on every inconvenient bolt on the dammed bike. You may be onto something with the pentrating oil. May dissolve that shit.

 
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Warming that gently with a butane torch will help break the bond, if it refuses to come out easily ... but to be honest, it looks like an easy one.

 
I just had to replace a caliper bolt on the '05. Why are the bolts hollow? I ordered 2 of them and asked the parts guy the same question.

He muttered something about "Cooling", then said "Perhaps to lighten the bike". I have to think it must be for the better cooling effect for the simple

thought of the amount of weight saved (?)

 
If the threads are cut all the way through the caliper then that broken piece of bolt should turn freely now that there is no tension. Have you tried to turn it with a tool that fits snug in the hole, like maybe a phillips head screwdriver? If it is stuck, then I'd try some heat, like Twigg suggested. That will loosen any thread locker that may be on it, and it will actually expand the hole so the bolt can break free. Apply the heat to the caliper, not the bolt.

 
I wonder if a complete flushing of the brake fluid from at least that caliper would be a good idea after heating the caliper to break the Loctite bond.

 
Reading the original post, this thing sheared while being installed so the OP knows if there is any Loctite. My 'guess' is there isn't but............

 
no locktite, just light grease and was tightening it like i did the other three.. this one didn't feel right, just spun... should have stopped but was waiting for the click of the torque wrench.

partshark.com

$2.36 for the part, and $9 shipping.

BOLT, WASHER BASED for 2004 YAMAHAFJR1300ABS FJR1300ASC/FJR1300AS 90105-105A7-00

is there anything else i should pick up to make that $9 shipping worthwhile?

 
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no locktite, just light grease...
Grease will change torque requirement by 30% or more, you need to reduce the torque by at least that much because the grease lubricates the bolt so it turns more easily. Anything that lubricates the threads will change the torque that should be used.

Torque is not a good measurement to determine clamping force because the condition of the threads of both the bolt and receiving threads will affect the true clamping force. Oxidation creates drag so torque will be too low; wax, oil, locktite, etc. will lubricate the threads and lead to over torquing.

 
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yikes.. i did not know that. thank you

is it bad practice to add a little grease to bolts then?

 
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Unless otherwise stated, torque values are 'dry'. If you use anti-seize or grease just be aware that it changes torque value and clamping force.

 
I broke one and it came out with no special tools. I just gave it a spray of WD-40, left it for a while, jiggled it with a screwdriver and it backed out. I didn't trust the others after that so I bought a full set of solid Titanium bolts off ebay.

 
I broke one and it came out with no special tools. I didn't trust the others after that so I bought a full set of solid Titanium bolts off ebay.
Not every metal does well, in contact with other metals. The farther apart any two metals are on the Galvanic Series list, the more quickly they will corrode, seize, or fail. Titanium does not like Aluminum at all. Moisture (humidity, cleaners, or rain) will make things worse. Racing parts are not intended to live long without frequent maintenance, or complete replacement. The correct anti-seize compounds for any use will have "intermediate" metals in them, to ease the transition between dis-similar metals. A copper-based anti-seize compound would be good where Titanium contacts Aluminum. See chart (scroll down there):

Galvanic Series Chart

Titanium bolts may be stronger initially, but galvanic corrosion can cause totally unexpected failures later.

Infrared

 
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