Topic: Cb750 k1 to f1/k7 front brake caliper and bracket differences

[Svrides]

Probably an old question, but I can't find information I'm looking for. I am sitting with 2 different later type caliper brackets and one type allen screw type caliper which only fits one bracket properly. Anyway what I'm looking for is information and or pictures showing/explaining which goes where per model as shopping for replacement parts is confusing suppliers nevermind myself. The thicker caliper bracket I was of impression was for later models but my existing caliper fits it correctly on the thinner arm. Can anyone enlighten me on where to search for this info or perhaps send me some pics on correct combination of parts? Thanks in advance

[newday777]

Welcome to the forum Svrides
I don't have pictures nor could I find them in a search. I'm going to notify a mod to move this to the SOHC Bikes section as there might be more traffic of members to see this there.

BTW, rather than saying 'later' say what year as there is too many changes possible when you say later years.

[Svrides]

Thanks for welcome msg, my confusion with the calipers and brackets stems from the 1975/6/7 bikes seemingly have different parts altogether from 1970 to 75 K's. The f1/0 & k7/8 (1975-77) seemingly use same calipers and brackets. Or maybe I should say caliper arm as mounting hardware to fork slider appears to be only 2 variants  'c' & what I call 't' type. If I'm not mistaken only 69 and some 70 bikes used early 'c' type. Now the calipers themselves varied more it seems depending on arm/caliper bracket fitted. The thinner arm is also different length,  can't remember which one is the longer although All

[newday777]

Are you sure that you don't have some 500/550 calipers and brackets mixed in? 🤔

[newday777]

A few threads to read through to help you find the information

http://forums.sohc4.net/index.php?topic=1594.0

https://www.sohc.co.uk/index.php?topic=4211.0

[scottly]

The "C" brackets were used from K0-K2, then the mounts on the fork changed to accept the "T" brackets from K3-K6 with early style finned calipers and also the K7-K8 F0-F1 smooth calipers. The arms are specific to each of the three versions. You simply can not fit the K3 and up calipers to early forks, or vice-versa. I've tried.    

[newday777]

The "C" brackets were used from K0-K2, then the mounts on the fork changed to accept the "T" brackets from K3-K6 with early style finned calipers and also the K7-K8 F0-F1 smooth calipers. The arms are specific to each of the three versions. You simply can not fit the K3 and up calipers to early forks, or vice-versa. I've tried.

So the second picture is the C bracket?

[Svrides]

Thanks scottly for some clarity, so to complete my F1 I will need to obtain a smooth caliper. On top of that concern I will have complete my K's forks to do trial fit as sliders length is different to the F1, they shorter and use different internals. In theory the complete finned caliper assembly I have should be fine there. What I figured out is the shorter sliders(about 1inch)forks would be correct for my K although not model correct, it's being built as a form of "gentleman express" so I won't get crucified for that lol.

newday777, yup already checked that I'm using correct size caliper as 550 caliper,  although smooth, is different size bolt mount distance. Thanks for the threads I will go check them out.

Thanks gents I now have direction to get at least one set of front brakes operational.

[Svrides]

Further thanks to newday777,  read threads you mentioned and now between those and replies from you two gentlemen I am suitably informed and can get done,  hopefully I get chance to take F1 for quick spin before packing for my impending move next month. Happy times ahead

[bryanj]

I think the piston diameter varies as well allong with the seal, you can check on line parts lists like cmsnl to see what changes when

[newday777]

Thanks scottly for some clarity, so to complete my F1 I will need to obtain a smooth caliper. On top of that concern I will have complete my K's forks to do trial fit as sliders length is different to the F1, they shorter and use different internals. In theory the complete finned caliper assembly I have should be fine there. What I figured out is the shorter sliders(about 1inch)forks would be correct for my K although not model correct, it's being built as a form of "gentleman express" so I won't get crucified for that lol.

newday777, yup already checked that I'm using correct size caliper as 550 caliper,  although smooth, is different size bolt mount distance. Thanks for the threads I will go check them out.

Thanks gents I now have direction to get at least one set of front brakes operational.

You are welcome.
The 750 K7 and K8 have a lot of different parts from the K6 and earlier, longer fork sliders than K0-K6 as well as the smooth calipers with different size piston, seal, brake pads and bracket. I didn't know of the bolt spacing difference, so I learned that now.

K7/K8 brake caliper fiche
https://www.southsoundhonda.com/--xpartsstream#/Honda_Powersports/CB750KA_(78)_750_FOUR_K%2c_JPN%2c_VIN%23_CB750-2800001/FRONT_BRAKE_CALIPER/14cf52cd-d282-42e1-9a4b-99870811a8c4/bc6e78ec-dc4a-441f-843d-bd302d83a644/y

You never told us until now what you have for a bike, so it's is a F1, 75 or 76? Please let us know what you have when asking for help. That helps save some confusion.

Go to the new members section and introduce yourself and your bike. Pictures are always good.

http://forums.sohc4.net/index.php/board,58.0.html

[newday777]

Here are some identifying charts, where you are from South Africa(according to your profile input)? That could make a difference in what you have too depending on where the bike was imported from later lin it's life or if it was a direct import for original sale.

And a couple pictures showing the fork legs of the k2-K6 fork sliders(left- shorter) and K7/K8 slider(right- taller). The K2-K6 have a 341 raised stamp between the bolt bosses.

[newday777]

The F0/F1 sliders, caliper w/ hex head bolts, and the caliper mount are different part numbers from the K2-K6 models. So without pictures from you, and you saying that you have a F1, your caliper and mount most likely are the 392 F1, and are the same part numbers as the K7/K8 according to the fiches.

K7/K8 front caliper
https://www.southsoundhonda.com/--xpartsstream#/Honda_Powersports/CB750KA_(77)_750_FOUR_K%2c_JPN%2c_VIN%23_CB750-2700009_TO_CB750-2729534/FRONT_BRAKE_CALIPER/488d4742-027b-4b51-a833-a0b6f2ea4cd6/bc6e78ec-dc4a-441f-843d-bd302d83a644/y

F0/F1 front caliper
https://www.southsoundhonda.com/--xpartsstream#/Honda_Powersports/CB750FA_(76)_750_SUPER_SPORT%2c_JPN%2c_VIN%23_CB750F-2000003_TO_CB750F-2022317/FRONT_MASTER_CYLINDER_%2b_FRONT_BRAKE_CALIPER/e65ffa8d-6805-4211-95ff-c44dded3b19c/da651074-0703-43a9-8a61-19432a2f8ac5/y

[newday777]

I'll try to remember to look and measure the brackets this afternoon when I get back in the shop(it's 6am here north of Boston). I have K models from K4-K6 and a K8 so I can verify thickness and length differences.

[Don R]

 I've swapped the complete F0,1/K7,8  brake and bracket to a late 341 shorter fork leg. The 341 lower was also used on some 550's with a shorter chrome tube.

[bryanj]

341 also fitted to disc brake 450 twin with 500 tubes