83 GS1100E Front Master Cylinder Options

[KiwiAlfa156]

I've had very mixed results on Aliexpress. I have found it's a fantastic way to get ripped off or at a minimum get your funds tied up and require you to dispute charges UNLESS you're dealing with a reputable seller. Can you supply the specific seller you used?

Thanks,

Steve

Here you go Steve.

Letgoing Co., Ltd.(CHN.)


Just search for "PX1 16mm"

The only other thing to be aware of, is the banjo bolt (which it ships with) is 1.25mm pitch (stock Suzuki is 1.0mm) This is only important if fitting a switch type banjo for the brake light.

[snoobler]

The nice thing about Ed's solution is that it works fine, and appears to be a stock (unless one is truly a GS1100 expert) master cylinder.

And yeah, the anti-dive. I have block off plates on two of my anti-dive equipped bikes, and still functional anti-dive on the other. Oddly enough, I've gotten the mushiness out of the bike with the functional anti-dive units to the point it feels just as tight as the blocked off units do. By switching to stainless brake lines, and following the bleeding procedure outlined in the factory service manual to the Nth degree, you can get good results, if you want to keep the stock appearance.

Thanks. I hear you.

I didn't mention it, but I've had stainless lines on this bike (GS1) for 15+ years, and I have followed the Suzuki shop manual bleeding procedures multiple times. GS2 recently had stainless lines installed and an ebay aftermarket master cylinder that looks almost identical to the EX650 one pictured above, but it's performance is pretty mediocre. I'm hoping to find a better solution for both.

[Griffin]

The nice thing about Ed's solution is that it works fine, and appears to be a stock (unless one is truly a GS1100 expert) master cylinder.

And yeah, the anti-dive. I have block off plates on two of my anti-dive equipped bikes, and still functional anti-dive on the other. Oddly enough, I've gotten the mushiness out of the bike with the functional anti-dive units to the point it feels just as tight as the blocked off units do. By switching to stainless brake lines, and following the bleeding procedure outlined in the factory service manual to the Nth degree, you can get good results, if you want to keep the stock appearance.

[snoobler]

If you really want to improve your braking
performance with stock calipers, fit one of these.

It's made in China (like Brembo is) and the quality is superb. Cue the misguided comments on "Chineseium". Ordered on Aliexpress they land at my New Zealand doorstep for about NZD $90.00. Which is about USD $55.00, although with the tariff that 'somebody' pays.. it might cost you more. Lever feel is awesome and is fully adjustable. It allows confidence inspiring control. The radial master cylinder seems to convert more of the lever pressure to caliper squeeze. The one in the pic that I took 10 minutes ago is five years old and when I resurrected the Katana 750 a year or two ago, the choice to fit one to that bike was a no-brainer. The brand is Adelin.

I've had very mixed results on Aliexpress. I have found it's a fantastic way to get ripped off or at a minimum get your funds tied up and require you to dispute charges UNLESS you're dealing with a reputable seller. Can you supply the specific seller you used?

Thanks,

Steve

[snoobler]

You need a 5/8" bore master (or 16mm). Don't buy 14mm, or the lever will feel very soft and spongy.

I like the rectangular bore EX650 master. It has a proper threaded mirror post, with the same threads as common GS mirrors. And consider removing the anti dive junk, or at least disabling it. If you remove it, you need a block off plate, with a passage between the holes. Easy to make in your garage with a hunk of 1/4" aluminum plate, and a drill motor.

Any specific years? Does it have the brake switch as well? Both my GS anti-dive systems work pretty well, so I'm inclined to keep them as long as they do.

[KiwiAlfa156]

If you really want to improve your braking
performance with stock calipers, fit one of these.



It's made in China (like Brembo is) and the quality is superb. Cue the misguided comments on "Chineseium". Ordered on Aliexpress they land at my New Zealand doorstep for about NZD $90.00. Which is about USD $55.00, although with the tariff that 'somebody' pays.. it might cost you more. Lever feel is awesome and is fully adjustable. It allows confidence inspiring control. The radial master cylinder seems to convert more of the lever pressure to caliper squeeze. The one in the pic that I took 10 minutes ago is five years old and when I resurrected the Katana 750 a year or two ago, the choice to fit one to that bike was a no-brainer. The brand is Adelin.

[Nessism]

You need a 5/8" bore master (or 16mm). Don't buy 14mm, or the lever will feel very soft and spongy.

I like the rectangular bore EX650 master. It has a proper threaded mirror post, with the same threads as common GS mirrors. And consider removing the anti dive junk, or at least disabling it. If you remove it, you need a block off plate, with a passage between the holes. Easy to make in your garage with a hunk of 1/4" aluminum plate, and a drill motor.

P1010741 by nessism, on Flickr

[rphillips]

First of all WELCOME. Luckily I've not had the problems you've got, a rebuild of my orig. usually fixed my troubles, though the after mkt. kits are quite iffy. I do remember (I think, though I can't find it now), a front master from a Kawa. EX500 was recommended as a good replacement for our GS's, thinking needed to be from an early EX500 to get the threaded well for the mirror. Pretty dang confident somebody here will be along with a reasonable solution.

[snoobler]

Spent about 30 minutes searching - nothing definitive.

2X 83 GS1100ED - one with an aftermarket I'm not happy with, and the other with a stock master cylinder that needs a quick pump or two to perform. Yes. I have bled the living crap out of it. I spoke with Steve at Brake Crafters, and he concluded it sounded like the master cylinder was the issue.

Have already been down the rabbit holes in this thread before hitting a brick wall:

https://www.thegsresources.com/_forum/forum/technical-forums/tires-suspension-brakes/1709480-83-gs1100e-brake-system-rebuild-kits

At Steve's (Brake Crafters) recommendation, I tried the universal 14mm piston EMGO master cylinders:

32-37281

https://emgo.com/wp-content/uploads/2021/08/2019general_IN-2967-1.pdf

Got them from CyclesRUs since Brake Crafters doesn't offer them.

Unfortunately, their quality was COMPLETE garbage. There was paint INSIDE the reservoir, and the threads were so boogered, I couldn't start a bolt let alone the mirror post. Worst of all, it wouldn't build any pressure except during the last 10% of the pull after every form of bleeding known to man (bench, banjo, gravity, vacuum, pressure, manual).

I bought TWO, and they were both the same. They also behaved oddly - when the lever was pulled, a large jet of fluid exited the ports. When the lever was released, little to no fluid jetted back into the reservoir. I mucked with these things for about 4 hours - went through nearly 32 oz of DOT 4.

Videos/pictures: https://photos.app.goo.gl/rsSX6TEuBSZuCEMFA

Fortunately CyclesRUs gave me a full credit with evidence they had been rendered unusable.

I had the stock one re-installed, bled and fully operational in 15 minutes. I noticed the amount of fluid injected into the reservoir during pull was minimal with a large amount on the release. This suggests to me an issue with the port placing/spacing on the EMGO master cylinders.

Here's a link to the video of the stock master cylinder operation:

https://photos.app.goo.gl/NRfU54fTghU7qYAq6

If you compare the EMGO to the stock, it's notable the EMGO ports are notably closer together.

At this point I'm pretty desperate. Appreciate any help.

rphillips - I'm tagging you because I see that you have one in your sig and hope you've been down this road...