front brake troubleshooting

[MJ84]

Alright, let me set this up...

Bike is an 82 GS450L. My first bike that I still haven't been able to ride... Front brakes worked perfect before all this...

I had the bike up on center stand and jack while I was getting tires on the wheels, my dad walks past and somehow ("accidentally") knocks the jack out from under it so it lands on the front forks... (related??) Once I got the wheels back on I found the front brake didnt work. I open the fluid reservoir and find a gel gunk. I cleaned everything out, put new fluid in and got nothing. thinking the old line was clogged with the gel, (and it was the cheapest place to start) i replaced the brake line. still nothing.

Now - there is pressure at the master cylinder, but i don't know how much pressure there should actually be...
- there is very little fluid comes out of the caliper end of the line when i operate the brake. Shouldn't there be a fairly steady stream?

My question is basically master cylinder or caliper? Which is most likely causing my problems?

I am completely new to motorcycles, so any help, ideas, or suggestions you can offer will be great!

[Nessism]

You need to do a full system teardown and clean out all of that gunk. To take apart the master cylinder you need a pair of long nose circlip pliers. To get the caliper apart it's best to use compressed air to force the piston out. The service manual will provide details.

[Big T]

Your caliper is probably full of that gel as well

Unbolt it, remove the pads and old it over some kind of bucket. Squeeze the brake lever until the caliper piston pops out. Catch all that gel and brake fluid in the bucket

Get some Brake cleen and a scotch brite and clean out the caliper insides.

Check the piston for pitting.

Reassemble, bleed with new fluid and you should be good to go.

Do not use anything but brake fluid to lube the parts. Except for the slider pins, use silicone grease

And thank your Dad for saving you from a nasty crash.

What other systems haven't you checked as yet?

[BassCliff]

Greetings and Salutations!!

Hi Mr. MJ84,

There are very small passages in the master cylinders. These must be clean too. I think your Dad did you a favor by revealing a faulty brake system. That could have been disastrous. You'll find a caliper overhaul guide on my website along with lots of other GS lovin'.

Here's my "welcome thang"...

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[duaneage]

The Suzuki manual I have recommends denatured alcohol as a cleaner followed by brake fluid for assembly. Things need to be very clean. Get a new brake hose, small price to pay for your life.

The first time you stop a foot from a fender you'll be glad you did this right.

[Darkchyld]

I just had to do mine on an 82 1100 GL, did a full rebuild on the master and the calipers. Parts cost was more reasonable than I had expected.
Cleanliness is critical tho.. Mine had gelled up and the hoses were deterating from the inside filling the system with tiny bits of rubber and gunk. Once I had everything apart I used stoddard solvent to clean up, compressed air to blow everything out followed by a warm soap and water wash. Then I left the peices on the dash of my car in the sun for an hour or so. Surprising how hot they got but absolutly garranties they're dry. Lube up during ass'y with brake fluid then bleed...

DC