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Nothing here
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Well, take off three bolts ride around and let us know what happens. I'm sure they have figured out how much stress those bolts would have to take for them not to snap off and that 6 was the best compromise between strength and weight.
 

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Elitest thrill junkie
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7 minute abbs.
 

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Mr. Scary said:
Geoff Kabush only uses three Ti bolts on race day, you haven't stumbled onto something earth shattering. AMP's bolt pattern for their disc brake was three bolts. Cannondale used four. Hayes used six, Hayes disc brakes worked the best (at that time), so guess how six bolts were adopted as the standard?
well said!
 

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Engineering

Well, if yur bolts do manange to break apart and lead you into a horrendous crash, then you won't be able to sue. Being an engineer student, 6 bolts are built in with a safety factor and for the heaviest of people. Trying to stop a 150 lb person vs a 300 lb person is quite a bit different. Engineers designing it need to account for all sorts of variables, including the stupidity of the operator. So six bolts is probably a balance between all that and cost.
 

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Because it is just 7.2 grams

Some Guy said:
While moving a rotor from one wheelset to another, I got to wondering why rotors are held on with six bolts. Wouldn't three do the job perfectly well?
in titanium ... want to save 3.6 grams? ;)
 

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Some Guy said:
While moving a rotor from one wheelset to another, I got to wondering why rotors are held on with six bolts. Wouldn't three do the job perfectly well?
And the Darwin award winner is..... Some Guy!!! :D

Seriously - at least put some Al bolts there - washing your bike will probably save more weight.
 

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Some Guy said:
Considering the lengths people will go to save half a gram, I'm just curious why I haven't seen people using less than six bolts.
I'd vote for the fact that most people decided that the weight savings isn't worth the possibilty of thousands of dollars in dental work/medical bills. Try the Ti bolt suggestion and use 6 instead :)
 

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Cleavage Of The Tetons
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I am an advocate of using 3.5 bolts on race day, and 4.5 bolts for training. I also shaved all of the lugs off of my shoes, and shortened the arms on my sunglasses by 10mm.
 

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No known cure
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weight<bling

rideit said:
I am an advocate of using 3.5 bolts on race day, and 4.5 bolts for training. I also shaved all of the lugs off of my shoes, and shortened the arms on my sunglasses by 10mm.
Ti bolts definately do have more bling regardless of weight. ;)
 

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Faller - Expert Class
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Ugh...

...so NOW you guys tell me that velcro won't work!!!... :D
 

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Doesntplaywellwithmorons!
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3 bolts works fine, we're stopping bicycles not motorcycles here. The earliest for bicycle disc brakes of the modern (post-war) era used thread-on rotors for the most part until the mid-90s when bolt-on's took over because it made for faster/easier rotor changes, mainly on bikes being raced. When rockshox bought the amp brake design, they kept the 3 bolt format though in a different bolt circle diameter, even for the front DH setup on the boxxer forks (albeit with an undrilled 7.5" diameter rotor). If it was good for a 6" travel Pro DH bike in the late 90s, its good enough for most riders today.

Hayes didn't start with a clean slate of paper in making bicycle disc brakes like oh, Amp did. Instead they motorcycle disc brake designs, and most motorcycles had gone to bolt-on rotors with 6 bolts to hold them in place at the time.

When the biggest hub maker around (shimano) decided to settle on one design of bolt pattern, and went with the hayes pattern, it basically spelled the end for all other patterns unless the other disc brake manufacturers wanted to keep their customers locked to only a handful of available hub choices. That's why ChrisKing had their discotech hubs originally which used replaceable adapters to fit the different brands of disc rotors.

Cars which have a LOT of weight to deal with usually don't even have 6 bolts unless they're race cars. The disc rotor is usually held in place on most cars by the lug bolts that also hold the wheels in place. Why? Well if you happen to break the bolts, your wheel tends to come off first and that in most cases serves to stop the car just fine. The lack of a disc rotor kinda becomes moot then.
 

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Less bling with centerlock

bhsavery said:
centerlock rules.........

No kidding, its heavy but really its a more elegant solution (shimano propreity notwithstanding)
I guess one could get a King Ti lockring and tiodize it. Hmmm
 

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Has anybody ever heard of anybody shearing rotor bolts? Are 250lb guys getting away with only 6 bolts? As always for those of us who weigh less than 150, normal kit is overbuilt, and it's possible to save weight by cutting down without compromising safety. Having said that I still have 6 steel bolts on mine, but must switch sometime. I've heard 3 ti, 3 alloy works well?

I agree with the centrelock theory though. With good hub / rotor design it's possible to go lighter this way, and it's a lot easier to use too. IIRC a DT 240 centrelock plus adapter is lighter than a 6 bolt and bolts.
 

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wanna save some g´s just put 6 tit bolts and cut down as you may see the bolts have a little lenght not used ;)

"Cars which have a LOT of weight to deal with usually don't even have 6 bolts unless they're race cars." I like to feel it secure! i always use 6bolts becase my bike is always racing ;) every day is a race day :D

Bee Cool and ride safety!
 

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Got Mojo?
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Short stature rulz!

rideit said:
I am an advocate of using 3.5 bolts on race day, and 4.5 bolts for training. I also shaved all of the lugs off of my shoes, and shortened the arms on my sunglasses by 10mm.
And five toes? Come on, what is with all those digits? It is not like we need toes at all, we are not an apes, we don't pick stuff up with our feet.

And toes are rotational weight.

After removing my toes I could purchase smaller shoes. I would have to give my feet the appropriate time to heal though....

I am not sure all that time off the bike would be worth it.
 
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