Author Topic: which rotor is which...  (Read 812 times)

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Offline alacrity

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which rotor is which...
« on: March 12, 2015, 07:04:15 PM »
Sorry if I missed it, but a search didn't turn up a nice single list of all the front rotors on our various CB bikes.  I picked up a rotor at a swap meet a while back and it's a "smidge" bigger than a cb550 rotor.
I am gonna put it up for sale and wanted to check a reference or two to be sure which bike(s) it fits before hand.

ANyone got a link?

thanks
I recently restored and sold a 77 cb750f, and am nearly finished with a (former basket case) cb750k5.  This is a place to share, learn and enjoy.  I am grateful to and for 99+% of this site's membership.

Offline scottly

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Re: which rotor is which...
« Reply #1 on: March 12, 2015, 07:09:20 PM »
What's a "smidge"? ;)
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Offline 754

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Re: which rotor is which...
« Reply #2 on: March 12, 2015, 08:12:45 PM »
750 rotor is about 1.6 smidges bigger than 500 rotors..
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Offline mrfish2

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Re: which rotor is which...
« Reply #3 on: March 12, 2015, 08:45:13 PM »
I believe the 550 rotors have a 270mm or 275mm diameter (can't remember which) while the 750 rotors have a 295mm diameter.
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Offline scottly

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Re: which rotor is which...
« Reply #4 on: March 12, 2015, 09:15:10 PM »
750 rotor is about 1.6 smidges bigger than 500 rotors..
Hmm, then 1 smidge equals 12.5 mm, or .492"??! I always thought a smidge was much less, but thankfully I haven't had to deal with the Smidge system since selling the '53 BSA. ;D
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Offline alacrity

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Re: which rotor is which...
« Reply #5 on: March 12, 2015, 10:11:17 PM »
A smidge falls between a tad and a bit, as described in the rare 7side bolt head wankworth system


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I recently restored and sold a 77 cb750f, and am nearly finished with a (former basket case) cb750k5.  This is a place to share, learn and enjoy.  I am grateful to and for 99+% of this site's membership.

Offline alacrity

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Re: which rotor is which...
« Reply #6 on: March 12, 2015, 10:14:41 PM »


Y


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I recently restored and sold a 77 cb750f, and am nearly finished with a (former basket case) cb750k5.  This is a place to share, learn and enjoy.  I am grateful to and for 99+% of this site's membership.

Offline alacrity

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Re: which rotor is which...
« Reply #7 on: March 12, 2015, 10:18:59 PM »
Ok so it's for a 750. Thanks dudes.  296mm. And 7.07mm thick.  I don't need it.. Gonna put it in the classifieds here


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I recently restored and sold a 77 cb750f, and am nearly finished with a (former basket case) cb750k5.  This is a place to share, learn and enjoy.  I am grateful to and for 99+% of this site's membership.