GPz550 Communication 10/28 Issue. Recently? Brake master is “HONDA OEM horizontal mount” – achieving both performance and cost efficiency! Perfo

Good morning – it looks like we’re in for another rainy week.
While the heat is unpleasant, the rain is worse because it keeps me from going outside.

The GPz550 Communication that everyone loves is progressing steadily.
We’re working on it during breaks, so please rest assured.

When you buy a used bike, you definitely want to get the brakes, tires, and other chassis components sorted out first.
I’m planning to install my favorite Honda OEM horizontal-mount brake master that I’ve been using since the Zephyr 550.

I recently sold my CB1100 SC65 through KatieX.
The transaction isn’t completely finished yet, but it’s a “revolutionary motorcycle sales estimate and sales method.”
As a seller, there’s no personal information or fees involved, so there’s absolutely no burden.
I’ll report the details in a blog post later. *Even just the estimate is free!

Lever position adjustment is extremely important.

Obviously, the farther away the lever is, the harder it is to grip.
Everyone has different hand sizes and preferred positions where they can apply force most easily.

Even small adjustments to fit your personal preferences make riding more enjoyable.
Of course, the closer the lever gets, the more the stroke decreases,
so balance is necessary.

Of course, with radial brake masters,
even minute position adjustments are possible, so they’re definitely racing spec.

5/8 inch (approximately 16mm) Honda OEM Front Brake Master (Nissin)
45510-MFM-C01

Here’s my favorite 5/8 inch (approximately 16mm) Honda OEM Front Brake Master (Nissin) 45510-MFM-C01

It’s not a complete assembly, so you need to purchase the “body/lever/pivot pin” separately.
*The brake light switch is included though.

There are also 11/16 sizes and others, which surprised me a bit.
You tend to choose brake masters based on piston diameter, but there are actually many things you won’t know until you install it.
That’s because
“piston diameter + lever pin ratio + lever shape and position adjustment” all work together to change the touch feel.
Since it’s a part where you can’t afford to make mistakes, it’s best to actually grip a bike that has it installed.

45510-MFM-C01 5/8 Master Cylinder Body
This comes with a brake switch included, so it’s very reasonably priced.
What I really like about this master is that the reservoir cap is slightly rounded, which looks nice aesthetically.

Also, the mirror holder is attached to the body with an M10 right-hand thread.
This is really useful when the mirror positions don’t match left and right.
And since the mirror holder is on the body itself, vibration is reduced slightly, so mirror visibility shouldn’t be compromised.

I think it’s a well-thought-out OEM quality part.

53170-MEJ-016 Lever

It offers 6-stage adjustment and is slightly hollowed out with a more modern shape.
But this master is used extensively on Honda bikes.
In other words, you won’t have trouble sourcing small parts in the future, making it a great item.

The grip feel is also quite enjoyable.

90114-MA5-671 Lever Pin
You can probably find black ones if you search, but the plated version resists rust well.
OEM parts are usually fixed with either a lock nut or a flanged nut.
To improve lever operation, I basically use a lock nut for fixing.
*Tightening too much can make the lever action stiff on some units.

Common OEM parts reuse issue: surprisingly, things don’t always fit together as-is

I’m reusing the brake hose as-is.
Since I’ll be replacing the front fork and surrounding components later, I want to remake the brake hose at that time.
But this particular bike has a mesh hose I’ve never seen before,
which looks pretty cool, so I decided to keep it.

As shown in the image, the brake hose retainer is making contact, so I’ll protect it and cut it off.

When I suddenly looked at the throttle cable… it has a very unusual layout.
By the way, the GPz550 throttle cable is discontinued.
I’m not sure if it will work, but I’ve already ordered the reproduction parts from the GPz400/F.
I want to share this kind of information with all the GPz550 owners out there.

In the old days,
I would have immediately wanted to swap the handlebar switch to a push-cancel type,
but now I’m starting to see the appeal in this clunky handlebar switch.
As you get older, things become more bothersome, or rather
“you find value in things that don’t exist in the modern world.” I recently realized that’s what it is.

You might think “Wait, you changed the brake master?” but
brakes are in a different category.

Time passes and installation is complete *Air bleeding still pending

The handlebar is drooping slightly, which is a bit concerning, but it’s fine.
The handlebar switch is large and it’s a handlebar clamp type, so there’s not much layout flexibility.

There’s no operational issue, but it’s less flexible than a bar-end setup.

The inspection window is barely visible… *Well, I don’t look at it that much anyway.
The mounting bolts are naturally steel! Flanged hex socket in tri-chromatic black looks cool to me.

The Zephyr 550 looks like this.
Looking closely, I see this one has a black lever pivot pin…

I really love these OEM customizations that nobody notices.
You need to keep a parts list for each bike or you’ll lose track yourself!