After a lot of work and money...it's official--no front brake at all

[mrbill5491]

Okay 5 pages, go buy a new one lol.

[oldrookie]

Okay 5 pages, go buy a new one lol.

I would, but which part do I buy?

Caliper? (Not available--and visual inspection shows a nearly pristine surface on all moving parts) MC? Brake line? Banjo bolts? Gets expensive just throwing money at it until it is solved. All of those parts can't be faulty at the same time, can they?

At this point, I have replaced the piston and cup set in the original MC twice, replaced the brake line with a stainless line (which is when this all started,) replaced the MC with a newer MC off a 2006 GS500, spent the money to repair the sight window in the newer MC, and have purchased 8-9 bottles of brake fluid. Not to mention what Suzuki dealer gets for the crush washers. Bwringer gave me some of the crush washers last spring or it would be even worse.


The bleeder was closed in the last video. It does move fluid when the bleeder is open, but not much. Mostly because it doesn't do anything until the lever has very little travel left.

Considering selling the bike. I haven't had the brakes right since March. Brakes are high on my list to have working correctly. Need to be working on the base gasket--but if I can't figure out how get brakes to work...do I really want to tear the heads off an overhead cam bike? It is a great little bike, but apparently I'm not much of a mechanic.

Going to reinspect the original MC and probably will reinstall it tomorrow to see if it works better. It was giving more power than the ebay replacement.

Will pull the caliper off again this a.m. before work and try hanging it above the MC.

[oldrookie]

Well, that seemed a bit whiney after I posted it, but whatever.

Here is the piston at rest:



Piston movement Click for video

[mrbill5491]

I would, but which part do I buy?

Caliper? (Not available--and visual inspection shows a nearly pristine surface on all moving parts) MC? Brake line? Banjo bolts? Gets expensive just throwing money at it until it is solved. All of those parts can't be faulty at the same time, can they?

At this point, I have replaced the piston and cup set in the original MC twice, replaced the brake line with a stainless line (which is when this all started,) replaced the MC with a newer MC off a 2006 GS500, spent the money to repair the sight window in the newer MC, and have purchased 8-9 bottles of brake fluid. Not to mention what Suzuki dealer gets for the crush washers. Bwringer gave me some of the crush washers last spring or it would be even worse.


The bleeder was closed in the last video. It does move fluid when the bleeder is open, but not much. Mostly because it doesn't do anything until the lever has very little travel left.

Considering selling the bike. I haven't had the brakes right since March. Brakes are high on my list to have working correctly. Need to be working on the base gasket--but if I can't figure out how get brakes to work...do I really want to tear the heads off an overhead cam bike? It is a great little bike, but apparently I'm not much of a mechanic.

Going to reinspect the original MC and probably will reinstall it tomorrow to see if it works better. It was giving more power than the ebay replacement.

Will pull the caliper off again this a.m. before work and try hanging it above the MC.

The MC unit, thought that was where the problem lies?

[oldrookie]

Mrbill, Could be an MC issue. Not sure of anything anymore.

Can't get the original MC for a GR650 anymore. I'll scout around and see how much a new one from a GS500 might run.

[mrbill5491]

Mrbill, Could be an MC issue. Not sure of anything anymore.

Can't get the original MC for a GR650 anymore. I'll scout around and see how much a new one from a GS500 might run.

Might want to look at Dennis Kirk, they have MC units, maybe you can find that works for you there.

[oldrookie]

Okay, thanks.

[oldrookie]

Went back to the OEM master cylinder. Got at least as much pressure as the brakes had all summer.

If I had to guess--the '06 MC from the GS500 I bought from ebay wasn't as "ready to go" as the seller stated. (I know, let me show you my shocked face.)

68 degrees here today and I'm going to take it out for a while. Hoping that it at least retains the pressure I got out of it this a.m.

Doesn't appear that the original suggestion--air leaking around the caliper piston--is accurate either. Took a fair amount of air being compressed into the caliper to get it out.

[chuck hahn]

Once the seals are seated properly and theres no corrosion in the grooves ETEC ETC ETC..then they should push in without much force at all. If it took a LOT of air to get them to come out..and they were coming out real slowly..then if it was my calipers i would be investigating that like looking for fly crap in pepper. I have done a lot of these and ( to me anyways ) that dsecription is very telling.

[oldrookie]

" i would be investigating that like looking for fly crap in pepper."

LOL! Haven't heard that one!

I'm going to have to find someone who has worked on brakes around here to take it on. I'm just not getting anywhere with this. Too many variables and I don't have the experience to know what I'm looking for.

Took it out for a ride---just got back, as a matter of fact---and they aren't any worse, but not any better either. Brings to a stop with planning, but better not have to do an emergency stop.

Frustrating, because it it running like a top.

[oldrookie]

I HAVE BRAKES!

Bwringer got it done! Went up to his place and rode it home a few minutes ago. Like an entirely new riding experience when you can trust your brakes!

Many, MANY, thanks to a very generous GS'er.

[Agemax]

so what was the solution in the end?

[chuck hahn]

Yes..do tell what Brian found!!!!

[tas850g]

I'm waiting for it too!

[oldrookie]

He said he'd post up what he found and how he fixed it.