Brake Feeling - Problem or not?

[J_C]

Hey guys... so kind of a different take on the brake thing. The GS1100L is my first cruiser. My other bike is an SV650S sportbike which obviously has a much different feel. The brake lever on the SV is almost immediately firm, requiring very little travel. The GS, not so much.

The GS' lever does need to be brought nearly all the way to the grip. The stopping time is longer than what I think it should be. The question is whether this is just due to the feel of a cruiser with all the extra weight it has, or because the brakes from 27 years ago arent as effective, or if I have a problem with my brake line.

I double checked to ensure there were washers between all the connections, and I rebled the bike (both normally and with the front end raised with the wheel off the ground.) If there is a problem with the lines, I might be inclined to think it's because they are... (ahem) 27 years old. I can firm them up a bit by pumping them repeatedly, but within 5 -10 seconds its back to the way it was. Even when they're firmed up its still not nearly as responsive as the SV.

Any advice is appreciated!

[Nessism]

You might want to consider a braded teflon brake line to firm up the lever. Rubber brake lines expand under pressure which lead to a spongy feel at the lever - worse on bikes with long cruiser handlebars because the lines are long. Teflon brake lines, with exterior stainless braided covering, expand very little and provide a firmer feel at the lever.

[focus frenzy]

yes, braided stainless lines are the way to go, my 1000G has a firmer lever than the SV1000 I have here because it has braided SS lines on it.
a good flush and bleeding would make a big difference as brake fluid is hygroscopic and absorbs moisture out of the air and that causes mushy lever and eats the aluminum of the master cylinder and caliper.

[chef1366]

My front brake lever also has quite a bit of travel. It doesn't hit the grip but it is close. My braking is good though. It is the old M/C. If you want better "feel" try a later model E model that has an brake lever adjustment.
It's hard to compare a modern sport bike's brakes to 27 year old cruiser braking system. I have ridden a SV and they do "stop on a dime".
Did you fix the M/C leak?
Also braided stainless steel brake lines will decrease the "flex" of your rubber lines and stiffen up the lever.

[J_C]

Thanks for the fast responses guys! I don't really want to replace the MC, since those tend to be pretty costly. It sounds like the braided lines will need to be a purchase, for the front brakes anyway. I really want better stopping power than I currently have. Currently, it is impossible to lock my front tire. (I tried) I'd rather rely on my skill than the lack of brake power to keep that from happening.

As for the MC leak, I have no idea what the deal is. It hasn't leaked in 3 weaks, so maybe the o-ring just needed to expand or something. I'm keeping an eye on it.

[chef1366]

Cool, the mystery fix!!!

[nabrams]

Are you sure there's no fluid (or other oil) leaking onto the brake rotor itself. My old original brake was quite firm - then one day it got really mushy - still working but significantly less stopping power and more mush at the lever.
Turns out there was some oil puddle that I'd rode through and it got oil all over the brake rotor, but it wasn't really very visible.
Some brake cleaner and a bit of riding, and my lever was back to its immediate bite, firm feel and good braking.

[J_C]

I didn't see any but I'll double check. Thanks for the tip

[robertbarr]

The fact that you can 'firm up' the lever by pumping it up indicates there's a hydraulic problem. If there's also an issue of limited friction, that's another (important but separate) story.

I'd start by bleeding every bit of fluid out of the system and replace with a freshly opened container. It could also be a problem with the MC, but might as well start with the obvious / easy fix first. A squeeze - trigger bleeding / vacuum tool would be pretty helpful in doing this.

[J_C]

Thanks for the info. I should have clarified that I had just put the system back together after disassembling the entire bike. The fluid is all new from a brand new container. I don;t remember how it felt prior to disassembly, though I thought it might have been the same. That's what led me to suspect it might be the lines. I had not considered that it may be due to a bad MC. DOh.

[DimitriT]

It's not just the lines that are 27 year old. The master cylinder is also probably in need of service and the caliper piston seal (and the piston itself) could probably need replacing too. I went through a complete rebuild on the 750 and added braided lines from HEL. The lever now gets tight almost immediately and there's very little travel.

Getting the last air bubble out of the system is also a very tricky process. Did you compress the caliper piston while you were bleeding it? Use a small c-clamp to comopress it in. I found that I also have to rotate the caliper around a bit to get all the bubbles up near the bleeder valve. Another place where bubbles can get stuck is in the banjos. Apply brake pressure and crack open the bolts to flush out any bubbles.

Ofcourse, take extra care when handling brake fluid. Nasty stuff.

[tkent02]

Test the master cylinder...
pull the lever softly, tiny amount of pressure. Hold it a long time, if the lever moves slowly in under light pressure it is going bad.
Most likely you need the new hoses and more bleeding.
Should be able to lock the front wheel easy enough.

[KapitalKat]

Yep, had this problem with my 1981 GSX750S. To get good firm lever pressure, I have used the following with great success. Using a saw tooth type tie down clamp, by pumping the brake lever a few times and then tying it off around the throttle grip as in keeping the pressure on. If left say overnight when released the system seems to have gotten rid of those annoying little air bubbles which normal bleeding struggles to dissapate. I have used this many times and works great. Probally not 100% correct thing to do but hey it works!!:-D

[Surly]

Same "Problem" Exactly

Hey guys... so kind of a different take on the brake thing. The GS1100L is my first cruiser. My other bike is an SV650S sportbike which obviously has a much different feel. The brake lever on the SV is almost immediately firm, requiring very little travel. The GS, not so much.

The GS' lever does need to be brought nearly all the way to the grip. The stopping time is longer than what I think it should be. The question is whether this is just due to the feel of a cruiser with all the extra weight it has, or because the brakes from 27 years ago arent as effective, or if I have a problem with my brake line.

I double checked to ensure there were washers between all the connections, and I rebled the bike (both normally and with the front end raised with the wheel off the ground.) If there is a problem with the lines, I might be inclined to think it's because they are... (ahem) 27 years old. I can firm them up a bit by pumping them repeatedly, but within 5 -10 seconds its back to the way it was. Even when they're firmed up its still not nearly as responsive as the SV.

Any advice is appreciated!

My last bike was a Canadian-spec 2000 SV650S and the brakes were soooooooooooooooooooooooooooooooooooooo much better than those on my GS1000. But hey, the SV weighs what, 120-150 pounds less and is much more modern. Plus it is a fixed caliper system.

My GS does the same thing. Pumps up and feels really good, then crunches my fingers the next time I grab a handful. I've bled using a Mity Vac and a homeade pressure bleeder with identical results. Tried every tip on the forum and no change. I agree with the rest of the guys, stainless lines should firm things up and hopefull make for a more consistent feel. I'll put them on if I can chase down my carb gremlins. Otherwise, I'll add them to a new Bonneville.