im having bad problem brakes

[jtrip]

hey im new here ,

im having troble with my gs850gl the front brakes keeps locking up and i have to release pressure so i can move dont know what is wrong with it i changed the fluid it runs clear. i just can use the breaks but . if i do it gets hard to pull then brake lockup can anyone give me some advice ?? or do i need to find a new caliper and where can i find one im saying its a 850gl but i dont know cause it just says gs850l so its my first bike and i just would like to ride please help

[BassCliff]

Greetings and Salutations!!

Hi Mr. jtrip,

I would suggest a caliper rebuild and new stainless steel brake lines, maybe even a master cylinder rebuild. When you add the fluid and bleed the lines, make sure there is no air or water in the system. Air and/or water in the system will expand with heat and lock up the brakes. Let's get on with your "mega-welcome". It has a TON of GS850G lovin'.

Anyway, I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", the Carb Rebuild Series, and the Stator Papers. Now let me roll out the welcome mat for you...

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[Big T]

Your seals are old and hard, the brake piston may be pitted with rust and there may be something else other than brake fluid in there, like crystallized brake fluid

Take them apart and post up some pictures

You'll likely need rebuild kits for all your calipers

[SqDancerLynn1]

At a minimum you need to rebuild the master cyl. The fluid return port is clogged

[Big T]

At a minimum you need to rebuild the master cyl. The fluid return port is clogged

Some times I forget the obvious

But, you should be have taken the calipers apart and made sure there is nothing bad in there after 25 years of who knows how much maintenance

[Nessism]

As the others have already said, it's time for a brake system rebuild. If you are not capable, I'd try to find someone who is - maybe someone around here will help you.

[jtrip]

thanks guys for the help im thinking if i could just buy a caliper i will but dont know where to buy one and what bike caliper would fit my bike as in another bike any ideas??

[BassCliff]

Hi,

There are at least 10 online OEM vendors listed in your "mega-welcome". And there's always ebay too. Plus there are "Parts Wanted" and "Parts for Sale" sections in this forum. Finding parts is usually no problem at all.


Thank you for your indulgence,

BassCliff

[TooManyToys]

.....
I'm having trouble with my gs850gl the front brakes keeps locking up and i have to release pressure so i can move don't know what is wrong with it i changed the fluid it runs clear. i just can use the breaks but . if i do it gets hard to pull then brake lockup can anyone give me some advice ?? or do i need to find a new caliper and where can i find one I'm saying its a 850gl but i don't know cause it just says gs850l so its my first bike and i just would like to ride please help

If releasing pressure by opening up a bleeder screw or cracking a banjo fitting releases the brake then you most likely either have a clog in the compensating port of the master cylinder, or you have a hose that has an internal tear that acts like a one way valve.

The hose(s) is(are) something that's not terribly hard to replace with some mechanical skills, but you also need to get new copper washers if banjo fittings and bolts connect the hoses.

The master cylinder would be to be disassembled, cleaned, an inspection of the master cylinder bore to insure that it is in good shape and the master does not need to be replaced, then new internal parts if available can be acquired.

While several people here can "talk" you tough it, the inspection of the bore and reassembly of the master is critical. If you are uncomfortable with that, it's best to take it to a dealer as a front brake is essential for good stopping ability.

If the bike has been in storage for a while or not well maintained, it's really a good idea to rebuild all of the brake components as they are the biggest safety factor on a bike.

[mike_of_bbg]

At this point, even if you buy another caliper, you're going to want to rebuild it before you use it. (can one still buy a new caliper?) So you might as well rebuild the one you have!

However, as pointed out, it's really probably the master that's at issue here. There's a tiny relief hole in your master cylinder which is plugged. As the brake fluid warms up it expands, and can't get back into the reservoir so just creates pressure against the caliper. Does your master cylinder have the rectangular reservoir or a round one?

The reason the hole gets plugged is because you have contamination in your brake system. Some reading suggests that happens because of the porosity of the rubber brake lines. Hence the suggestion to go with SS braided lines. You can build your own from raw line, buy parts and assemble, or buy a complete line (probably a kit actually if it's dual calipers, which I assume it is). That may help with the creation of new contaminants but you'll want to rebuild calipers and master to be sure any existing gunk gets out and isn't hurting anything. BassCliff sent you his mega-welcome, and their are links on his page demonstrating caliper and MC rebuilds I think. See the "Brakes odds-n-ends" section for the MC overhaul instructions.

Some have replaced their MCs with (usually much newer) ones from other bikes. You can use almost any master cylinder meant for a bike with 7/8" handlebars and dual calipers (IIRC all 850s had dual front calipers?). If meant for another line of bikes you will need to adapt the brake light leads to your bike.

If your bike has chain drive, then it's probably just an L (assuming the side cover isn't lying to you). If it has shaft drive, it's a GL. What model year is it? Most of us find it helpful to go click the "user CP" link and add a signature with our bike(s) in it so folks will have a clue what we're talking about when we forget. You can also put a location in and maybe somebody will see that and say, "hey, I'm not too far from you: I'll come by and lend a hand".

[jtrip]

its the round master cylinder i only have one caliper on the front i see in the master that there is a hole where the fluid goes to the break line but i dont see another hole there how small is it ?? and if i find it how deep does it go

[tukn20s]

I have an 1978 GS750 with dual fronts and my bike is doing the exact same thing. The brakes will work fine for a while (as in driving around for a little while) and with use, the brake lever slower gets firmer and firmer until the calipers start to hang up. If I loosen a bleeder or banjo bolt the calipers will let loose.

I suspect a bad line or MC to be the problem. I hope to get to it this weekend. If you find the cause of your problem, please let us know as I will do the same. Good luck.

[mike_of_bbg]

its the round master cylinder i only have one caliper on the front i see in the master that there is a hole where the fluid goes to the break line but i dont see another hole there how small is it ?? and if i find it how deep does it go

It's quite small, and it's under the reservoir. Only a few mm deep. You'll need to bleed the brake fluid out of the master and remove the reservoir: there should be two philips head screws inside holding it down. Use care with the reservoir because they can get somewhat brittle after a few decades. You'll probably need a small, firm wire or needle to clean out the hole. Replace the reservoir (a new o-ring is recommended), fill and bleed the system, and give it a test. If successful, please don't let that success make you complacent about overhauling the rest of the brake system!