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8" rotors.

tubs26

Chimp
May 12, 2011
65
0
so on my bike I have 6" rotors and i always liked the look and feel of 8" i understand they have more braking power and take longer to heat up so you can use them longer and not get brake fade. what I am trying to figure out is, is it worth it to get 8" rotors or should I just stick with my current mechanical brakes or buy something new, like bb7's and have 8" with those. my current brakes are hayes mec. idk what model or anything. when I first got the bike the back brake was good! but when I got home. (it was rubbing a lot because the rotor was bent so I messed with the brakes and screwed it up. But I was able to get the rotor back to straight) I have been tinkering with them every night and I thing i need to clean the pads and rotors.

So in other words what are your guy's opinion on 6in vs. 8in, what do you recommend, stuff like that.
 
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Yeti

Monkey
May 17, 2005
877
0
yeti cave@the beach
Like Quo Fan said, first upgrade to hydraulic brakes. If you do long technical downhills and you're heavy, then 8" rotor in the back might make sense. If power is not so much the problem, but the fading, then I'm pretty sure you're not braking right and you're dragging the brakes. Brake when you need too and then let them be.
 

jonKranked

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Nov 10, 2005
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Unless you are downhilling, 8" rotors are overkill. Decent hydraulic brakes will work better than any mechanical brakes.
agree with this about 95%... 8" rotors might not be a bad idea for a trail bike if you are a clydesdale or if you live in an area with long, long descents.

fwiw i know some smaller dudes that DH run 7" rotors
 

tubs26

Chimp
May 12, 2011
65
0
I pretty much ride a hardtail bike, i kinda do XC, freeride, and DH. I usually have to ride to my local trails since I dont drive, I was not saying I get brake fade (at least not on my usual trail I ride) but what I am trying to accomplish with 8" rotors is I want a bike that can really do any type of riding, i hate being limited to your equipment. what I mean by that is say I go out riding and go on some trails I've never been on, i dont want to be like "this hills too steep i wont be able to stop, I cant ride this trail." etc. I would feel more comfortable with 8 or 7" rotors because I know I can trust them and wait to brake until I really need them, instead of grabbing 3 fingers worth of brake and having to guess when to start braking and be a slow poke because I dont know what's behind that next turn so I want to have brakes that can be responsive and forgive my mistakes. if all that makes sense.
 
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HardtailHack

used an iron once
Jan 20, 2009
2,260
163
Yeah I'm a fatty and anything under an 8" brake is a waste of time for me(except for DJ bikes), I don't know if you need an 8" on the rear of a hardtail as if the trail is rough you can't really use the back brake all that much, however I guess if it's steep, smooth and you drag your brakes an 8" rotor may help.

Running DH tyres may reduce how often you need to brake as you can corner at higher speeds, it all depends on your riding style I guess.
 

tubs26

Chimp
May 12, 2011
65
0
oh and btw I'm probably going to keep my brake choice mechanical. I know hydraulic are a lot better at performance, but I like mechanical brakes because they are cheaper, easy-er for me to understand and adjust myself, and you can do cool colored brake cable for like $14 instead of hydraulic brakes, the cables are like $30-$40, and you have to consistently get them bled. not to mention on mechanical brakes you dont have to worry about boiling your fluid.
 

jonKranked

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Nov 10, 2005
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FWIW you'll get better performance out of hydraulic brakes with 6" rotors than you will with mechanical disc brakes and 8" rotors.
 

tubs26

Chimp
May 12, 2011
65
0
that's true, but for the cost one one brake you can buy 2 mechanical brake AND rotors. not to mention my shifters are brake and shifter combos,therefore I would have to buy 2 new single shifters too, and they run like $30+ each so for front and back hydraulic brakes i would be paying like $250 when i only really want to spend $100 at most.
 
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lovebunny

can i lick your balls?
Dec 14, 2003
7,237
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San Diego, California, United States
for a quality mechanical brake like the BB7, you will spend like 70-80 for one caliper. then you ad another 50 dollars each brake for an 8" rotor. where as you can get an inexpensive hydraulic brake like the magura MT2 for 110-120 and they come with 6 inch rotors.

then all you have to do is cut the brake lever off of your shifter and youre good to go. thats what we do on a lot of old mountain bikes with canti brakes but blown out shifters. its cheaper to just cut the shifter off the brake lever and put a 15 dollar shifter. this would be the same just opposite.
 
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smittybit

Chimp
May 15, 2013
9
1
Parry Sound, ON Canada
I hate 8" rotors, my buddies ride had a 8" front rotor (for a month anyways ;)), was super annoying at speed on pavement or hardpack. Shing shing shing-aling-aling shing shing. At speed they tend to vibrate. Buddy started riding with fronts ever so lightly applied to get rid of it, replaced it pretty quick.

Agreed with earlier, no downhill or hercules braking needed, skip the 8s.
 
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jonKranked

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Nov 10, 2005
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I hate 8" rotors, my buddies ride had a 8" front rotor (for a month anyways ;)), was super annoying at speed on pavement or hardpack. Shing shing shing-aling-aling shing shing. At speed they tend to vibrate. Buddy started riding with fronts ever so lightly applied to get rid of it, replaced it pretty quick.

Agreed with earlier, no downhill or hercules braking needed, skip the 8s.
some of the worst arm chair engineering i've ever seen. rotor was either out of true or his calipers weren't properly aligned. plenty of people have been using 8" rotors for years without experiencing "high speed vibrations" :rolleyes:
 

smittybit

Chimp
May 15, 2013
9
1
Parry Sound, ON Canada
some of the worst arm chair engineering i've ever seen. rotor was either out of true or his calipers weren't properly aligned. plenty of people have been using 8" rotors for years without experiencing "high speed vibrations" :rolleyes:
Rotor was true, calipers were aligned, but thanks.
Seen plenty of 8" rotors without 'high speed vibrations' have you? ~ thanks, glad to hear it. This one had high speed vibrations.

This is the second rude-ass reply to me in under an hour, are you the local 'I'm a dick, and everyone loves me for it, so let me introduce myself' person? Have fun with that. Post count doesn't equal more knowledgeable buds.
 

jonKranked

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Nov 10, 2005
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Rotor was true, calipers were aligned, but thanks.
Seen plenty of 8" rotors without 'high speed vibrations' have you? ~ thanks, glad to hear it. This one had high speed vibrations.

This is the second rude-ass reply to me in under an hour, are you the local 'I'm a dick, and everyone loves me for it, so let me introduce myself' person? Have fun with that. Post count doesn't equal more knowledgeable buds.
i can't control my laughter at the "high speed vibrations". must be magic. if there's pad rub, somethings out of alignment. plain and simple.

and you're the "noob possibly a spambot" that keeps bumping dead threads. that's a quick ticket to banhammer.
 

tubs26

Chimp
May 12, 2011
65
0
what are you talking about? back when i had my actual DH bike the disks vibrated ALL THE TIME! (on concrete and gravel) it annoyed the hell out of me! no rubbing was heard, proper spaced calipers and it rang all the time! like a damn phone lol