Mushy brakes on an 82GS750E ?

[Guest]

I just got done going through the brakes on my 82 with antidive and have been bleeding the brakes. Used the prescribed order for bleeding from antidive left to caliper to antidive R and caliper. Rebuilt calipers, and master cyclinder, also redid the top end of the antidive units.
I haven't done the new lines yet but even so, the feel on these brakes is very mushy compared to the feel on my 450 and the 750T which have old lines as well(I know, I know, I have a new SS 450 line all ready to go and will be ordering new SS lines for this bike soon). Is it the antidive units? I have read that the feel is different on the antidive equipped bikes versus those without.

[spyug]

I think you are right and its a reason many of us block off the anti-dives. My Kat and 750 both came with them blocked off and they were a snap to bleed. On the other hand, my 550 anti-dives were still working and I had a bitch of a time trying to get things to firm up. After a week or so I gave up and deactivated the a/d.

As soon as I had done it, the lever firmed right up.

They can be done successfully, I know. Our bud Gatekeeper did his. Maybe he'll chime in and give you some pointers.

Good luck,
Spyug

[Cdnpt1]

So it sounds like that is normal operation then. My concern is taking it out on the road if things aren't right but if this is how the system normally operates then I will just have to get used to it. Or block off the AD. My main ride was an Aprilia Tuono so I expect a completely different feel and necessary change up in riding style but this just doesn't feel right.

[GateKeeper]

Prior to my rebuild, the brakes on the bike felt just fine, I had no issues, front or back and anti dive was active

Now, I have rebuilt the bike, I did add new SS lines, and I did keep the Anti Dive units, I had no issues in bleeding the system, doing just as you did and in that order, I did feel though that the front could be a bit tighter, so I pumped the lever multiple times, and tied it back and left it overnight, in the morning I released it, and now it seems to be much better and gets hard after only about a half pull of the lever

I don't know how good that is, as I have not taken the bike on the road, is it enough to work correctly or not, this I will only be able to tell once the bike is actually moving on the road, and hopefully I don't end up doing a Fred Flintstone and having to use my feet to stop....

I did a full overhaul of the calipers, new pads, new SS lines, new brake oil, only thing I did not overhaul was the MC on front or back, they were OK visually, I did clean them out and they were spotless, this was on front and back

[Cdnpt1]

I tied mine off over night as well, then did a rebleed because they just didn't feel great, got some tiny bubbles out of the left, right seemed pretty good. I tied them off again last night so I will see when I get home tonight. I was having to put 9 to 10 pumps in them to get a firm feel but it was improved after the first night tied off. I can see the calipers shift with one pump though so I know there is pressure in the system even though the feel is mushy. I have a rebuilt master cylinder on there and I see fluid onthe handle in the area of the piston, but I figured that was residual from some slop when I was bleeding. I wonder though.
When I was bleeding, as I let the handle go to it's resting position, fluid would on occassion literally shoot back out of the reservoir from the return port. I have never seen that before. A bit of ripple but not a jet of fluid. Also, I know the two fluids are seperate in the AD unit, but I currently have the forks drained as well. That shouldn't effect anything though right?

[GateKeeper]

So I just squeezed the lever and before it got to the bar it was already good and hard...

Boy does that ever sound dirty......

and now if I pump the lever it gets to a point of being really hard and hardly any movement after about 2 pumps.

get all of the brake fluid cleaned up, if you have a leak this will not be good and will cause you loss of brakes, ruined paint job, and you could get hurt if they fail all together.

forks with out oil, should not have an effect, I at least hope not.....

and maybe the stream your getting on return is or could be a cause because the system is so clean now.....it's actually working ?

.

[Cdnpt1]

Lol, i wasn't going to touch that line, too easy : ) I will take a look again when i get home and if no joy then I will order up a new master cylinder rebuild kit and SS lines and go from there.

[mrbill5491]

Buy the block off plates for the antidives and be done with it then use a little heavier fork oil. Matter of fact I use 30wt in mine to help prevent the fork dive some, seems to work fine.

[Cdnpt1]

Well, I got in touch with Rennsport and he put a complete set of six SS lines in the mail the same day for $129 total, and then I ordered a set of the 1.10Kg springs from Sonic. I am looking at a set of used Hagons forthe back to keep things matched up. I am hopefull that after I get the new lines on things will firm up, and a thorough cleaning of the forks will help the anti-dives back to better operation. I considered the block offs for the AD units but I want to keep this bike and the T as close to original as possible. The extra E will get modded a bit in it's time.

[GateKeeper]

instead of the block off plate, you could just use a screw/bolt where the brake line goes on the AD unit, and then use a single banjo bolt on the caliper end with your one ss brake line.

Just a thought,,,saw Sypug do this on his 750......

Cheers

[Cdnpt1]

The new SS lines came in today, will switch those over tomorrow and if no change may try plugging the AD's