Alternate front brake master?

I was just wondering what would be a good alternate front master cylinder for my 82 GPz750. I have a KZ750L top triple clamp and drag bars. The original MC barely fits and I'd like to get a little more room on my bars. Is there a donor setup that works well? What about rigging up a 5/8 rear MC and mounting it down behind the brake junction and actuating it via cable? I would prefer to reuse a MC as opposed to going aftermarket just for the cost savings and I get some satisfaction out of repurposing. Especially if I keep it in the Kawasaki family.

No eBay APP ID and/or Cert ID defined in Kunena configurationNo eBay APP ID and/or Cert ID defined in Kunena configurationAftermarket will be the easiest and least expensive way.



If you don't want chinese

No eBay APP ID and/or Cert ID defined in Kunena configurationNo eBay APP ID and/or Cert ID defined in Kunena configuration

The_Proletariat wrote: Aftermarket will be the easiest and least expensive way.



If you don't want chinese

The reservoir is what is getting in the way.

The remote res is what I'm probably looking for. NISSAN Builds most the MC for our bikes so there has to be one from a Kawasaki that would work. I'm just trying to get info on what is known to work well for my application. I'm not very big on the plastic specimen cup perched on the bars though. That's why I was wondering abut the remote MC so I could put it below the bars on the forks.

I believe the reservoir must be above the master cylinder bore in order for the brake system to work and possibly so the reservoir doesn't leak (the KZ650-C1 reservoir cap is vented even though the vent isn't obvious). Ed

650ed wrote: I believe the reservoir must be above the master cylinder bore in order for the brake system to work and possibly so the reservoir doesn't leak (the KZ650-C1 reservoir cap is vented even though the vent isn't obvious). Ed

I think it's more about gravity feeding fluid to the cylinder. That's why I'm thinking about the remote MC mounted on the forks or triple tree so I can lower the res. Looks like Kawasaki didn't use any rear MCs bigger than 14 mm that I've been able to find yet and if I'm not mistaken I don't want go any smaller than the current 5/8" or 16 mm bore cylinder.

GPzMOD750 wrote:

650ed wrote: I believe the reservoir must be above the master cylinder bore in order for the brake system to work and possibly so the reservoir doesn't leak (the KZ650-C1 reservoir cap is vented even though the vent isn't obvious). Ed

I think it's more about gravity feeding fluid to the cylinder. That's why I'm thinking about the remote MC mounted on the forks or triple tree so I can lower the res. Looks like Kawasaki didn't use any rear MCs bigger than 14 mm that I've been able to find yet and if I'm not mistaken I don't want go any smaller than the current 5/8" or 16 mm bore cylinder.

It is going to be difficult substituting a rear master cylinder for a front. It is uncommon to see a rear dual brake setup. In fact I have never seen a bike so equipped.

If you know of a bike with dual rear brakes I would research what bore size that master cylinder is (if such a bike exists).

You may have to use HD parts.
www.fabkevin.com/shop/parts/brakes/remote-master-cylinder/

Add length to your handlebar. I've welded extentions to get extra room on bars. The welds were hidden under the grips and it looked great.

The_Proletariat wrote:
It is going to be difficult substituting a rear master cylinder for a front. It is uncommon to see a rear dual brake setup. In fact I have never seen a bike so equipped.

If you know of a bike with dual rear brakes I would research what bore size that master cylinder is (if such a bike exists).

You may have to use HD parts.
www.fabkevin.com/shop/parts/brakes/remote-master-cylinder/

It's not about how many calipers it WAS operating but how much pressure you can get out to where it needs to go. Since the original MC is 5/8 I figure that's a safe place to start give or take a mm.

That's pretty much the set up I had in mind...except the price. I just need to find the MC.

80B4 wrote: Add length to your handlebar. I've welded extentions to get extra room on bars. The welds were hidden under the grips and it looked great.

Well that's a option I'm also thinking I could go with replacing the specimen cup with one if those pretty aluminum eBay-special reservoirs.

GPzMOD750 wrote:

The_Proletariat wrote:
It is going to be difficult substituting a rear master cylinder for a front. It is uncommon to see a rear dual brake setup. In fact I have never seen a bike so equipped.

If you know of a bike with dual rear brakes I would research what bore size that master cylinder is (if such a bike exists).

You may have to use HD parts.
www.fabkevin.com/shop/parts/brakes/remote-master-cylinder/

It's not about how many calipers it WAS operating but how much pressure you can get out to where it needs to go.

It is also about, (and just as important as pressure), the volume of fluid displaced by the master cylinder piston.

Dual brake systems (front, in your case) use a larger bore master cylinder than a single brake system (rear) this is why you are going to have a hard time finding a rear master cylinder (smaller bore) that will work for your front brake (larger bore).

The_Proletariat wrote:
It is also about, (and just as important as pressure), the volume of fluid displaced by the master cylinder piston.

Dual brake systems (front, in your case) use a larger bore master cylinder than a single brake system (rear) this is why you are going to have a hard time finding a rear master cylinder (smaller bore) that will work for your front brake (larger bore).

Pretty much meant that in not as many words. As such that's why I am looking for the rear that matches the bore of the front. Apparently, HD uses one.

One of the purposes of starting the thread is to see if anyone had experience which would suggest another approach.

I thought of another issue. Rigging up a brake light switch. I think I'll be taking a trip to the bone yard this week.