ST1100 brake rotor diameter

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I need to know the inside diameter and the outside diameter for a non-abs front brake rotor for any year ST1100?

I am doing a brake project on one of my other bikes and need to know if the rotors will fit. But I need to know OD and ID first.

Thanks
 
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'97 ST1100
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687
I need to know the inside diameter and the outside diameter for a non-abs front brake rotor for any year ST1100?

I am doing a brake project on one of my other bikes and need to know if the rotors will fit. But I need to know OD and ID first.

Thanks
OD is easy, 315mm

ID depends on what you're referring to

inside diameter of entire assembly 145mm
inside diameter of brake swept area 250mm

I've got a pair off the bike, I can measure anything you need.
 
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Grabcon
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dwalby. That is exactly what I asked for thanks. But since you have a pair that are off. what is the bolt hole circle diameter?
 
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687
That appears to be 166mm (center-to-center of the holes).

The bolt holes themselves are 10.5mm with a dial caliper, which I would assume is a nominal 10mm bolt hole. Also, there's a recessed area around the bolt hole that measures 17mm diameter and is 2-2.5mm deep.
 
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687
If you have any other questions about dimensions I can take a picture of one of the rotors with a tape measure in the picture. Then you could zoom the picture in something like Photoshop until the tape measure in the picture matches your actual tape measure, and you'd have a full size on-screen model to measure from.
 

Uncle Phil

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All discs are interchangeable between models as far as the bolt pattern/size is concerned. The ABSII discs are actually smaller than the standards but will bolt up to a standard wheel and vice versa. I'm running standard discs on an ABSII front rim on my 97 standard (so I could run the wider 120 tire). If you put ABSII discs on a standard wheel, the discs will not 'reach' into the standard calipers (BTDT for testing purposes! ;-))
 
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Grabcon
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I am working on a 1976 CB750F that I have built over the last couple of years and I am doing a front brake caliper and possible rotor upgrade. Not enough brake on the bike at the moment. I just pickup a set of Tokico 4 piston calipers and now I need to remove the front wheel and get some rotor measurements to see if the ST rotors will fit. The ST rotors are 19mm larger than what I have and with the new calipers the braking should be much better.

Existing brake setup. Factory 1981 CB900F brakes. Trying to move to the 21st century technology.

Fred Front right wheel.jpg
 
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Grabcon
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Thanks for all of the help. I found out exactly what I needed to know. I most certainly can use the ST1100 non ABS rotors on my project. They are a direct bolt on to my wheels.

dwalby. let me know if you are interested in parting with the rotors you have via PM.

Thanks again.
 
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