Increasing Brake power - new front master brake cylinder??

[Guest]

Hi,

I have a GS550 with two front discs. I find the brakes poor - have bleed etc

Has anyone tried to upgrade the master brake cylinder to a modern system, but kept the original brakes?

I met a guy who said the modern master brake cylinders have a 19mm 'hole' & can push more fluid through.

thoughts????

[tatu]

Have you removed the pads and cleaned the white ally corrosion between the pad and holder?

GS1100 calipers are a good upgrade, the ones with square pads make a big difference, also new hoses ie goodridge or the like help a lot as the hose gets old it expands and much of your lever action is lost there.

[pete]

I've rebuilt my 450's caliper and am using a new 13mm M/C from Mikes XS. This is a different size to what's required for the dual discs though.

Between the new M/C, rebuilt caliper, and the new braided stainless line I'm really happy with the strength and feel of the brakes now, and it's only a single disc.

The stock M/C for the singles is a 14mm one, and going down to the 13mm means a little more lever movement but more power, so I have increased feel and increased power from the M/C.

So, my suggestion is a caliper rebuild if you haven't done it, braided steel lines, and maybe a new piston and cup set for the stock M/C to start with. You'll probably think it's a new bike just by doing those bits...

Alternatively, if they're compatible, there's always the Kawasaki twin pot/Salty Monk upgrade

http://www.thegsresources.com/_forum/showthread.php?t=185121

[willie]

Have you removed the pads and cleaned the white ally corrosion between the pad and holder?

While you're at it, clean and lube (with ceramic brake grease) the contact area where the caliper slides on the mounting bracket. The front brakes on the most recent G I bought felt like 2 blocks of wood gripping an oily disc. They were terrible! I cleaned and lubed the above areas and couldn't believe the difference.
Willie

[jwhelan65]

Brakes on mid 80's bikes are marginal in comparrison to modern day bikes. The best way to maximize what you have without re-inventing the brake system is to replace the old lines with new SS braided, flush the calipers, check the piston seals, grease the pins, new pads, M/C rebuild kit and bleed thoroughly. When your all done bleeding compress the brake lever and duct tape it to the grip and let it sit over night, this will allow all the air bubbles if any to surface. This should give you the best results without any major upgrades.

my .02

[Vmass]

Brakes on mid 80's bikes are marginal in comparrison to modern day bikes. The best way to maximize what you have without re-inventing the brake system is to replace the old lines with new SS braided, flush the calipers, check the piston seals, grease the pins, new pads, M/C rebuild kit and bleed thoroughly. When your all done bleeding compress the brake lever and duct tape it to the grip and let it sit over night, this will allow all the air bubbles if any to surface. This should give you the best results without any major upgrades.

my .02

Just reccently rebuilt my fronts.....I did grease the pins, should the pad slides be greased as well?

[jwhelan65]

Just reccently rebuilt my fronts.....I did grease the pins, should the pad slides be greased as well?

I usually apply a small amount to the slides as well..

[Nessism]

Suzuki used a 5/8" (about 16mm) bore master cylinder on dual disc bikes. Moving to a 19mm master will make the brakes feel firmer, but it will make the hand effort required increase. As Pete alludes, going down in bore diameter might help, but you should upgrade the brake lines to stainless to avoid the lever coming all the way back to the grip.

Cleaning out the system through a complete tear down, changing the brake lines, and changing the brake pads, is the logical place to start. If the brake performance is still not good enough, talk to Salty_Monk for one of his upgrade kits. A master cylinder change is the last thing I'd look at unless you need a new master because the old one is corroded inside.

Good luck

[hampshirehog]

Ditto all above. Thorough clean and try stainless lines first. The next upgrade (which is a bolt on) that I would go for is to fit GSX750 1983 onwards calipers (GS850 are the same but I can't remember what years - early years are not an upgrade) If your calipers need rebuilding fit new stainless pistons and only fit the rubber seal but not the protector boot.

[salty_monk]

All being well I might be coming to the UK in January so if you do want a set I can bring one over... save you some postage.

I did all the possible "GS" upgrades, new stainless lines etc before I moved to the Kawasaki brakes.. the difference is night & day.