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SthFRider

Monkey
Apr 16, 2008
218
0
Atlanta,Ga
So i've heard some people say they don't run all 6 rotor bolts. I've heard some of the WC guys unly run 3 or 4 per wheel. But i guess it doesn't matter for them because they have a gazillion back up parts. Just wondering if anyone uses less than 6. If so how many and what kind of set up. Just curious. Cheers
 
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Tootrikky

Monkey
Jul 31, 2003
772
0
Mount Vernon
I've been running 3 bolts/disc since I started racing in 2001 (saw a picture of Nico with only 3). They do come loose a little more often, but never caused me any major issues (yet!).
 

ALEXIS_DH

Tirelessly Awesome
Jan 30, 2003
6,147
796
Lima, Peru, Peru
i run 3 in the front, 2 in the back.

i think saving 6 grams is absolutely worth the risk of fatal injury or a wheelchair bound life.

you know what 6 grams means when you ride at my stiff-knees, stiff-elbows rear-wheel-brake-dragging, 32% body fat level? man, am sure i could qualify for the WC if could only run with 2 ti bolts on the front.
 

roel_koel

Monkey
Mar 26, 2003
278
1
London,England
you wanna save weight on your rotor bolts whilst staying safer with no bolts snapping or coming loose?

run good quality titanium rotor bolts (6/4 with rolled threads) and blue loctite


1/2 weight of steel so you can run all 6, and have properly secured rotors....


I don't run them for weight savings on my all-mountain bike, I just hate rusty bolts ;)
 

Tayrob

Monkey
Jan 3, 2008
105
0
6 on my DH and trailbike.
3 on my XC and slalom bike.
Dunno why I do it.I just do.
 

wood booger

Monkey
Jul 16, 2008
668
72
the land of cheap beer
I used to run three, and I would check them all the time. The rear rotor came loose on a ride and almost caused disaster.

I wouldn't run any less than 6 on a rotor bigger than 160mm.

The main reason WC DH mechanics do it is to cut down on rotor swapping time.

Like stated above, run 6 Ti bolts if weight concerns you.
 

NoUseForAName

Monkey
Mar 26, 2008
481
0
Hmm, i think i am going to invent a new way of fixing rotors onto hubs. Maybe one big nut that threads onto the hub and makes rotor changes super quick.

Oh wait, Centrelock. That would have been a cool name huh.


Maybe now that SRAM is giving in on 15mm axles, they can give in on centrelock VS 6 bolt.
 

Sghost

Turbo Monkey
Jul 13, 2008
1,038
0
NY
I used to run three, and I would check them all the time. The rear rotor came loose on a ride and almost caused disaster.

I wouldn't run any less than 6 on a rotor bigger than 160mm.

The main reason WC DH mechanics do it is to cut down on rotor swapping time.

Like stated above, run 6 Ti bolts if weight concerns you.
If roadies are ditching the TI bolts on stems, TI on rotor bolts probably isn't the wisest course of action.
 

bdamschen

Turbo Monkey
Nov 28, 2005
3,377
156
Spreckels, CA
I wouldn't run any less than 6 on a rotor bigger than 160mm.

The main reason WC DH mechanics do it is to cut down on rotor swapping time.
Just wanted to re-quote this for the n00bs.

I still don't see the point of that either, hasnt anyone heard of a cordless screw driver?
 

gemini2k

Turbo Monkey
Jul 31, 2005
3,526
117
San Francisco
I've been running 4, front and rear, all my bikes for several years. I'm a big guy and I've been told I overuse the brakes. 4 is just fine as long as you're not a moron and use loctite and torque it down enough. I've never had 1 come loose, ever.
 

TomBo

Monkey
Jan 13, 2004
300
0
Calgary,Alberta
3 Ti Front, 3 Ti Rear, 3 full seasons of riding over the last 5 years, saved at least 3 mins of of race time, over the seasons. Jeebus only knows how much time of "freeriding".

Really did run this, then swapped to a different bike, that must weight 5lbs more. Times are the same... I wasted a lot of money on a sub 40 bike.

P.S. never did have a mechanical with the 3 and 3.
 

16v

Chimp
Oct 7, 2009
46
0
thread derailment, but how did the standard rotor bolts end up being torx head when virtually everything else on the bike uses hex bolts?

oh, and i run all six bolts. I dont see a reason to take off any...
 

Tootrikky

Monkey
Jul 31, 2003
772
0
Mount Vernon
I've been running 3 bolts/disc since I started racing in 2001 (saw a picture of Nico with only 3). They do come loose a little more often, but never caused me any major issues (yet!).
I am pretty sure my post is like on of those "Social Networking" announcements that keep you from getting jobs and so forth, and therefore it would be wise to delete it...Screw it I live life with only 50% of the torx installed...dangerous
 
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Udi

RM Chief Ornithologist
Mar 14, 2005
4,915
1,200
Yeah in theory, except in practice they don't need that much torque, and torx heads suck in general thanks to a notoriously shallow head depth (especially on the button head screws used for rotors).

I have been running 3x Ti per rotor (red loctite, never had a loose bolt) for the last 4 years with no dramas. The only issue you run into is getting them back out again without wrecking the torx heads because the loctite is brutal, thankfully I've used the same hubs about that long as well.

I'd recommend loctite for people having them come loose, because in my experience, 3-4 bolts per rotor won't fail (given that they stay there), while an arbitrary number of tight bolts between 0 and 6 thanks to loosening would be quite dangerous.
 

Sghost

Turbo Monkey
Jul 13, 2008
1,038
0
NY
Cannondale and Magura ran 4 steel bolt systems for years, but with 3 bolts there is little room for failure. I certainly dont know anyone whos mechanic sends them home in the off season with 3/6 bolts though. XC or DH.
 

DhDork

Monkey
Mar 30, 2007
352
0
Hell, AZ
thread derailment, but how did the standard rotor bolts end up being torx head when virtually everything else on the bike uses hex bolts?
I actually have a friend, a lifer in the industry, who runs Torx for pretty much all of his bolts on his bike. Claims it was actually really cheap and easy to switch them all over, and never rounds out a bolt head.
 

RMboy

Monkey
Dec 1, 2006
879
0
England the Great...
I just use 6 quality steel bolts front and back.....you know to be different. we dont have titanium on the island yet ;-)

Maybe focus my time on saving weight on bigger items, like wheels.. :-D
 

gemini2k

Turbo Monkey
Jul 31, 2005
3,526
117
San Francisco
but i can save 15 grams!!!!:cool:
I think for most of us who run fewer than 6 its mostly about convenience, not weight. There's really no reason to have 6. It's a HUGE margin of safety. Much bigger than other "over engineered" parts of your bike Personally, I'm more concerned about something the likelihood of the 4 bolts clamping my handlebars coming loose.
 

IH8Rice

I'm Mr. Negative! I Fail!
Aug 2, 2008
24,524
494
Im over here now
I think for most of us who run fewer than 6 its mostly about convenience, not weight. There's really no reason to have 6. It's a HUGE margin of safety. Much bigger than other "over engineered" parts of your bike Personally, I'm more concerned about something the likelihood of the 4 bolts clamping my handlebars coming loose.
how much time are you really going to save by not installing 2 more short bolts? do you switch wheelsets that often?
if time is of issue, why not have a small cordless drill to spin them out faster?

i know having only 4 bolts isnt a huge safety factor. i was using 4 bolts back in 2000 when Foes used a 4 bolt hub on their F1 fork.
 
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MarkDH

Monkey
Sep 23, 2004
351
0
Scotland
I drilled out my hubs and now run 12 bolts per rotor. When you ride at the speeds I do, 6 just doesn't cut the mustard.
 

Pslide

Turbo Monkey
I think for most of us who run fewer than 6 its mostly about convenience, not weight. There's really no reason to have 6. It's a HUGE margin of safety. Much bigger than other "over engineered" parts of your bike Personally, I'm more concerned about something the likelihood of the 4 bolts clamping my handlebars coming loose.
I'm guessing the force on those rotor bolts is a few orders larger than the force on the bolts on your stem. And the rotor bolts are smaller. And in shear.
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
21,031
5,921
borcester rhymes
um, i may be mental, but it looks like that actually could have been prevented by running six bolts vs. three. Each bolt location (which is missing) is where the rotor appears warped. Is that just an optical illusion?
 

OGRipper

back alley ripper
Feb 3, 2004
10,647
1,116
NORCAL is the hizzle
um, i may be mental, but it looks like that actually could have been prevented by running six bolts vs. three. Each bolt location (which is missing) is where the rotor appears warped. Is that just an optical illusion?
No, I think you're right, and I think that's the point. Pretty crazy, haven't seen that before, but it's another reason to run six bolts.
 

yuroshek

Turbo Monkey
Jun 26, 2007
2,438
0
Arizona!
me neither...

here is a pic of a Formula rotor that completely wrapped under heat - snapped this pic after a shuttle un up in Ashland this summer:

Why so hard on the brakes? Lay off them a bit and you wont have this problem :thumb:

Oh and for the record I dont know how many bolts I run.