Author Topic: Total Caliper Confusion CB750f  (Read 3138 times)

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Offline Sdsbassist

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Total Caliper Confusion CB750f
« on: August 25, 2018, 08:24:40 AM »
So, I've been trying to research the correct items for myself here but I am falling misrably short.

I have a 750f model. From what I've read there was a few discrepancies between the F and K front calipers of that year.

My last attempted ended up with the rotor hitting the arm.

Can anyone help me with interchangeability of the calipers and arms for the early model Fs?

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Gus, Austin, MN.
Current Bike:  75 750F

Past bikes: 76 750K - "Iowa Blue",78 750K Craigslist find - "Black Beth;" 77 CB750K Basketcase, with a 75K engine; 1970 Cb750 K1, "Rosa Luxembourg"
74 cb750, 75 cb550, 77 kawa 650, 81 virago 750, 83 virago 920, 80 Honda Twinstar 200, 71 Honda CT70, 1971 Honda CB750 Rat Project "Black Dahlia Bitsa"

Offline scottly

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Re: Total Caliper Confusion CB750f
« Reply #1 on: August 25, 2018, 08:36:08 AM »
That's a 550 caliper. They look similar to the F0,F1,K7 and K8 calipers, but are smaller and fit a 275mm rotor instead of the 750 295mm rotor. The 550 has a 38mm piston, while the caliper you want has a 42.8mm piston. You can use a K3-K6 finned caliper and matching arm, but they have a smaller 38mm piston.
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Offline Sdsbassist

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Re: Total Caliper Confusion CB750f
« Reply #2 on: August 25, 2018, 08:37:49 AM »
Amazing. I dug through my pile and found an arm that clears the rotor.

Success!

I'm guessing the caliper you describe is going to be tough to find. What other models is it interchangeable with? With the a model?

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Gus, Austin, MN.
Current Bike:  75 750F

Past bikes: 76 750K - "Iowa Blue",78 750K Craigslist find - "Black Beth;" 77 CB750K Basketcase, with a 75K engine; 1970 Cb750 K1, "Rosa Luxembourg"
74 cb750, 75 cb550, 77 kawa 650, 81 virago 750, 83 virago 920, 80 Honda Twinstar 200, 71 Honda CT70, 1971 Honda CB750 Rat Project "Black Dahlia Bitsa"

Offline scottly

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Re: Total Caliper Confusion CB750f
« Reply #3 on: August 25, 2018, 08:46:06 AM »
The A model *may* have also used the larger caliper. The arms are not interchangeable between the different 750 calipers. Post a pic of the arm.
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline Sdsbassist

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Re: Total Caliper Confusion CB750f
« Reply #4 on: August 25, 2018, 09:42:40 AM »
The A model *may* have also used the larger caliper. The arms are not interchangeable between the different 750 calipers. Post a pic of the arm.
See

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Gus, Austin, MN.
Current Bike:  75 750F

Past bikes: 76 750K - "Iowa Blue",78 750K Craigslist find - "Black Beth;" 77 CB750K Basketcase, with a 75K engine; 1970 Cb750 K1, "Rosa Luxembourg"
74 cb750, 75 cb550, 77 kawa 650, 81 virago 750, 83 virago 920, 80 Honda Twinstar 200, 71 Honda CT70, 1971 Honda CB750 Rat Project "Black Dahlia Bitsa"

Online Don R

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Re: Total Caliper Confusion CB750f
« Reply #5 on: August 25, 2018, 09:57:29 AM »
 I'm a big fan of the double F0/1 front disc. I even cut up two rotor fenders and made a right side fender.
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Offline scottly

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Re: Total Caliper Confusion CB750f
« Reply #6 on: August 25, 2018, 10:28:54 AM »
That is the correct F0/F1 K7/K8 arm; it's thicker in the area where the caliper halves mount, while the early arms are flat. If you look at the 550 caliper, you'll notice the mounting bolts are closer together than the 750, so that's one way to identify which caliper you're looking at.
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline bryanj

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Re: Total Caliper Confusion CB750f
« Reply #7 on: August 26, 2018, 08:06:03 AM »
The F1 caliper is the rarest and most difficult to find but I believe Dave Silver has had some replicas made
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline Sdsbassist

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Re: Total Caliper Confusion CB750f
« Reply #8 on: August 26, 2018, 09:12:42 AM »
Think I found one...

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Gus, Austin, MN.
Current Bike:  75 750F

Past bikes: 76 750K - "Iowa Blue",78 750K Craigslist find - "Black Beth;" 77 CB750K Basketcase, with a 75K engine; 1970 Cb750 K1, "Rosa Luxembourg"
74 cb750, 75 cb550, 77 kawa 650, 81 virago 750, 83 virago 920, 80 Honda Twinstar 200, 71 Honda CT70, 1971 Honda CB750 Rat Project "Black Dahlia Bitsa"

Offline Sdsbassist

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Re: Total Caliper Confusion CB750f
« Reply #9 on: August 27, 2018, 02:44:36 PM »
On the correct caliper, what should be the distance bolt hole to bolt hole?

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Gus, Austin, MN.
Current Bike:  75 750F

Past bikes: 76 750K - "Iowa Blue",78 750K Craigslist find - "Black Beth;" 77 CB750K Basketcase, with a 75K engine; 1970 Cb750 K1, "Rosa Luxembourg"
74 cb750, 75 cb550, 77 kawa 650, 81 virago 750, 83 virago 920, 80 Honda Twinstar 200, 71 Honda CT70, 1971 Honda CB750 Rat Project "Black Dahlia Bitsa"

Offline scottly

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Re: Total Caliper Confusion CB750f
« Reply #10 on: August 27, 2018, 05:31:09 PM »
The center-to-center distance of the 750 caliper bolts is 50mm, or about 1.97". The 550 caliper spacing is 42mm, or about 1.65".
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline RAFster122s

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Re: Total Caliper Confusion CB750f
« Reply #11 on: August 27, 2018, 05:48:06 PM »
You should be able to sell the 550 caliper easily along with it's mounting hardware/brackets.
David- back in the desert SW!

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Total Caliper Confusion CB750f
« Reply #12 on: August 29, 2018, 06:34:52 PM »
This Honda 45100-392-003 CALIPER ASSY. (TOKIKO) fits the following models and components:

Honda Motorcycle 1976 CB750A A - 750 HONDAMATIC FRONT BRAKE-CALIPER

Honda Motorcycle 1976 CB750F A - 750 SUPER SPORT FRONT MASTER CYLINDER + FRONT BRAKE CALIPER

Honda Motorcycle 1977 CB750K A - 750 FOUR K FRONT BRAKE-CALIPER

Honda Motorcycle 1978 CB750K A - 750 FOUR K FRONT BRAKE-CALIPER

Honda Motorcycle Models with no year CB750F A FRONT MASTER CYLINDER + FRONT BRAKE CALIPER
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Sdsbassist

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Re: Total Caliper Confusion CB750f
« Reply #13 on: August 30, 2018, 06:36:31 PM »
I just snipped this lot off ebay for a cool 40 bucks. Looks promising... definitely 2 inches between bolts. Figure between that, the arm and the switch and cylinder I'm bound to come out ahead.

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Gus, Austin, MN.
Current Bike:  75 750F

Past bikes: 76 750K - "Iowa Blue",78 750K Craigslist find - "Black Beth;" 77 CB750K Basketcase, with a 75K engine; 1970 Cb750 K1, "Rosa Luxembourg"
74 cb750, 75 cb550, 77 kawa 650, 81 virago 750, 83 virago 920, 80 Honda Twinstar 200, 71 Honda CT70, 1971 Honda CB750 Rat Project "Black Dahlia Bitsa"

Offline Sdsbassist

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Re: Total Caliper Confusion CB750f
« Reply #14 on: September 01, 2018, 09:47:10 AM »
Local yard found these.....they look smaller?

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Gus, Austin, MN.
Current Bike:  75 750F

Past bikes: 76 750K - "Iowa Blue",78 750K Craigslist find - "Black Beth;" 77 CB750K Basketcase, with a 75K engine; 1970 Cb750 K1, "Rosa Luxembourg"
74 cb750, 75 cb550, 77 kawa 650, 81 virago 750, 83 virago 920, 80 Honda Twinstar 200, 71 Honda CT70, 1971 Honda CB750 Rat Project "Black Dahlia Bitsa"

Online seanbarney41

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Re: Total Caliper Confusion CB750f
« Reply #15 on: September 01, 2018, 02:34:46 PM »
the smaller ones are 500/550 and will not fit or function on a 750
If it works good, it looks good...