what size disc brake rotor to get???

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ocho ninja

ocho ninja

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Jan 14, 2012
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Search up hope floating disk.

A lil pricey but combined with a good hydraulic caliper it provides very good stopping power.

Or if looks at agk.com under motorized bike parts they sell mini bike calipers that stop as good as some of the really high end mountain bike stuff
 
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5-7HEAVEN

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mrfubs said:
so i am putting a disc brake on the front wheel of my cruiser, can anyone that has had experience using disc brakes tell me what size brake rotor would be best for speeds up to 50 mph.

so far i have this rotor in mind 203mm.

http://www.ebay.com/itm/290780405903?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l264

Also could i get away with using just a cheap caliper? or a get a Shimano?
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For speeds of 50mph, you might need more than a single 203mm front disc brake. I'm using that size disc brake front and rear, and I usually ride less than 35mph.

It's those downhill stops @ 35mph that REALLY pushes my brakes to their limits.

One of my projects involves retrofitting Suzuki motorcycle 240mm front hydraulic disc brake with rear 203mm bicycle mechanical disc brake onto a cruiser frame. However, I wouldn't recommend it to normal MBers.

But then again, riding @ 50mph isn't normal, either.

If you're going 203mm disc brake, consider Avid brakes. That's what I use on my commuter bike..bld.
 
ocho ninja

ocho ninja

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I use a regular 160mm on my 99cc fourstroke build and it stops me with my 250+ arse pretty good with a moped drum In the back.

If its going to be your only brake I recommend the 203 with a good hydraulic... Some of the racing guys sware by the mini bike calipers though.

However no matter how good your brakes are, always give your self appropriate room to react
 
mrfubs

mrfubs

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awesome! i really appreciate the help! I rather buy the right stuff "do it once do it right"

The coaster brake will bring me to a stop but thats only riding in my neighborhood and not the road where i may need to stop a lot sooner in some cases.
 
Venice Motor Bikes

Venice Motor Bikes

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Mar 20, 2008
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I've used 160s on most of my bikes without any problems, (even on my race bikes)... But the old saying of 'Bigger is better' definitely can't hurt when it comes to stopping. ;)
 
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5-7HEAVEN

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I'd advise buying ONE 203mm disc brake first. Trial-fit for clearance problems, especially in the rear. On one of my frames, there is only 1mm-2mm clearance between the front edge of the disc and the frame. On my other cruiser frame, there is quite a bit of clearance.

If you have clearance issues, you can use a 203mm in front and a 160mm-185mm disc in the rear.
 
mrfubs

mrfubs

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I think if I where able to put a disk on the rear that would be sweet! but its a cruiser, unless I can do some sort of back wheel conversion to allow me to attach a disk?
 
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5-7HEAVEN

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mrfubs said:
I think if I where able to put a disk on the rear that would be sweet! but its a cruiser, unless I can do some sort of back wheel conversion to allow me to attach a disk?
Click to expand...
They sell bolt-on frame adaptors to mount front and rear disc brakes. I use one on my Diamondback cruiser frame. However, my frame was made to accept a multi-speed internal hub.

Your rear dropout might be too narrow to use a disc brake.
I say "probably", because I don't remember trying to fit a rear disc brake into a narrow cruiser frame.

Others might know for sure. What frame are you using?
 
F_Rod81

F_Rod81

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It just depends on your riding style and specific needs. I ride pretty rough and fast most of the time. I've had great success and no problems with Avid BB5 or BB7 mechanical disc brakes. Most versions come with weather proof pads. I have a dual disc setup on my 2 stroke bike. 185mm rotor on the front and a 180mm rotor on the back, using a dual pull lever. Great balance and unbelievable stopping power. As previously mentioned, your tires play a role in this as well. Good quality rubbers will benefit you in many areas.

Don't just buy that rotor and slap it on and think you cool. If you set it up wrong and attempt a sudden stop you're likely to go over the bars and have more problems.
 
mrfubs

mrfubs

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F_Rod81 said:
It just depends on your riding style and specific needs. I ride pretty rough and fast most of the time. I've had great success and no problems with Avid BB5 or BB7 mechanical disc brakes. Most versions come with weather proof pads. I have a dual disc setup on my 2 stroke bike. 185mm rotor on the front and a 180mm rotor on the back, using a dual pull lever. Great balance and unbelievable stopping power. As previously mentioned, your tires play a role in this as well. Good quality rubbers will benefit you in many areas.

Don't just buy that rotor and slap it on and think you cool. If you set it up wrong and attempt a sudden stop you're likely to go over the bars and have more problems.
Click to expand...
I ended up getting a Shimano Hydraulic BR-m446 set for $38 i Bought a 203mm rotor and still need to buy a 203mm adapter and either am going to buy a MTB suspension fork with disc tabs on it or TIG weld some tabs on my fork. Iv been looking at the RST capa fork is interchangeable 1" steerer tube or 1 1/8.
 
F_Rod81

F_Rod81

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mrfubs said:
I ended up getting a Shimano Hydraulic BR-m446 set for $38 i Bought a 203mm rotor and still need to buy a 203mm adapter and either am going to buy a MTB suspension fork with disc tabs on it or TIG weld some tabs on my fork. Iv been looking at the RST capa fork is interchangeable 1" steerer tube or 1 1/8.
Click to expand...
Check this out...

Disc adapter
 
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5-7HEAVEN

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I bought one of those adaptors. Unfortunately, the smallest size (16mm) was still too big for my 12mm dropout. I guess I'll have to shim it a bunch.

Other than that, it fit well enough, and a 203mm disc will fit my 130mm wide frame.
 
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