New to riding

[recda4th]

Hello, forgive me if I'm breaking any rules or I'm asking a question that's already been answered. I'm new to riding and the forum. I bought a 1982 cb750 custom a month ago before I started riding. And I just realized that there was no front brakes at all. Not a master brake cylinder, not a disk, even the junction block wasn't on there. I'm trying to install them all on my own. Here's what I bought and you can tell me what I'm missing or if I should be all good to fixing it.

-non OEM master cylinder from ebay
-non OEM front disk rotor from NICHE motors ebay (says it should fit)
-OEM right front caliper bracket (45210-MA5-006)
-OEM right caliper assembly (45200-461-751)
-a brake valve junction block (45127-461-003)
-a steel braided brake line kit from eBay (says it should fit)

One other thing I was missing was the screws that hold the right rotor I think. I'll attach a photo. Aside from if that's all I need because I'm really hoping it is.
-What is the part number for these screws that are missing?

-do I also somehow need to get a left caliper assembly and rotor?

-if I need to post this somewhere else please let me know
Thank you.

 

[mrtwowheel]

One brake caliper and rotor is better than none. It's your choice to use one brake or two on the front. If you use only one you will not need the junction block, instead use one longer brake hose without a junction block. You will also need a brake light switch, usually incorporated in the master cylinder and lever. Rotor bolts.....measure the depth needed and thread size and pitch, OEM is not necessary, I would prefer stainless. Good luck, get ready to ride. Any more questions, post them on this thread with pictures.

 

[recda4th]

Thank you so much for your reply. I'll return the junction box then. I could've swore I saw somewhere that the brake was a single disc somewhere but it's all good. Couldn't find another left brake caliper even if I tried

 

[recda4th]

Noob question again. How do I go about measuring the bolt size on the rotor?

 

[mrtwowheel]

A set of plastic calipers works good for that. Do you have any spare metric bolts around? Find a metric bolt that easily fits, that would be your bolt dia. and thread pitch. You have an aftermarket rotor, better for you to measure the depth for your bolt length, may not be the same length as OEM. Cheap plastic calipers work good for measuring bolt diameter and depth too. It's handy to have a metric thread gauge, but not totally necessary when working on these metric bikes. Figure it out, that's a skill you're gonna need again when choosing hardware.

 

[mrtwowheel]

I steered you wrong, those bolts go through the hub and the hub is NOT threaded for the bolt. Go to Partzilla website it should give you the bolt size, washers needed and nuts. You should still check your length as you are using an aftermarket rotor and only one, may make a difference in length. Bolt Depot is a good source for hard to find hardware.

 

[recda4th]

I see so because the rotor is aftermarket I should shrink the size of the bolts to match up?

 

[mrtwowheel]

I see so because the rotor is aftermarket I should shrink the size of the bolts to match up?

Didn't say it would be shorter, I said it might be different, but yeah, probably shorter.

Check out #12 in the parts fiche, damping shim, pretty sure you should have two of those. those will change the bolt length too, and probably put your rotor in the right perspective to your caliper.

 

[mrtwowheel]

Notice, those are "flange" bolts and "flange" nuts. Flange, meaning they are shaped different than regular bolts and nuts but still readily available at hardware sources. Nylon lock flange nuts too, or at least use flange nuts and loctite. I don't see any washers used.

 

[mrtwowheel]

Not sure from your pictures if you have the damping shims and the dust seals, would have to be there hands-on to verify that.

 

[mrtwowheel]

Have you looked at the parts fiche at Partzilla? Most of your questions can be answered by comparing the parts fiche to the parts you have or don't have.

 

[recda4th]

Think I found the dust seals. And I bought a right caliper it looks like it has everything. Ill ask the seller. Here's the dust seals

 

[recda4th]

I think I saw what you're talking about about for the damping. Is this it? I don't see it on my bikes wheels

 

[recda4th]

Scratch the first one. If we're talking about the wheel then IDK if I have the dust seals either after looking. Is this what you're talking about?

 

[mrtwowheel]

I see you already have the dust seals in your last pictures of your wheel. You will only need one of those damping shims on the right side. The damping shims are kind of like gasket material. No need for one on the left side because your bolts would be bearing against it, that would not be good. On the right side the damping shim would be between the hub and the rotor.

 

[recda4th]

Got you. So I'll have to get one. I should put the damping shim on before I put the rotor right?

 

[mrtwowheel]

Got you. So I'll have to get one. I should put the damping shim on before I put the rotor right?

Yeah to that. I can measure the length for your 5 bolts later tonight, early morning. Taking for granted that your rotor is the same as stock thickness at the bolt area the other critical areas are subtracting one rotor and how much thread needs to be on the end of the bolts. Not able to do pictures right now.

 

[mrtwowheel]

What is the thickness of your rotor at the bolt/hole area?

 

[recda4th]

Hm... I'm not home right now to check. But looking at the rotor I bought. It says that it's a Direct Replacement For: 452A5-438-305, 45251-MK7-670, 45251-MF5-000, 45251-MA1-000, 45251-KW9-970, 45251-460-700, 45251-422-010, 45251-422-000, 45251-413-941, 45251-413-940, 45251-410-305, 45251-410-000, 45220-MB9-870, 45120-393-780.

I'd imagine if it's a replacement like this that fits so many wouldn't that mean it's sort of a universal size if it fits that many sizes? A better question I should say is there a basic universal width for a rotor already?

 

[recda4th]

A picture for a better representation*