Braided hose vs. master cylinder rebuild?

[FlightRisk]

My front brake on the CB500 is still not where I would like it to be after cleaning the caliper and replacing the fluid.
Despite doing the tie the lever overnight trick the brake is still a bit spongey and the lever comes back quite far before getting firm.

The pads are fine, the disc is worn and probably needs replacing soon but it's not warped, I see no signs of fluid leaking anywhere.

I'm wondering what to do next, I was going to order a HEL braided line but I don't want to be replacing bits for bling sake. For the same money I could order a master cylinder rebuild kit. I need a cheap fix really.
Any chance just stripping and cleaning the m/c and caliper might fix this?

What say the BCF braking team?
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Honda CB500S

[Itchy]

Re-bleed the master cylinder and the whole system.

A lot of people stop bleeding the brakes once the big bubbles are out of the system leaving it spongy.

You need to keep bleeding them until all the tiny bubbles are gone, meaning the overnight thing is not required.
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Spain 2008France 2007Big one 2009 We all die. The goal isn't to live forever, the goal is to create something that will. In the end, your life will flash before your eyes. Make sure it is worth watching.

[Busa1340R]

Have you a reason to suspect the master cylinder is at fault. Has the bike got high mileage or been used a lot for town work?

Does the lever come right back to the bar if held on for a while?

You may be suprised at how much difference a new disc makes, it doesn't necessarily need to be warped. A dished disc can also cause lever travel.

I suspect a braided line and maybe a pressure bleed may help, but could also mask the real problem.
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Current: 2010 Suzuki GSX1340R Hayabusa, 2013 Yamaha YP250R X-Max Sport - Previous: Triumph Sprint ST1050ABS, Honda XL600V Transalp, Honda NT650V Dullsville (don't ask!), Kawasaki ZX9R E1, Honda NX650 Dominator, Suzuki GSX1300RKZ Hayabusa, Honda CBR1000FM, Kawasaki GPZ500S, etc etc

[Kickstart]

Hi

How have you cleaned the caliper? Quick external wash out, or stripped down, seals out and cleaned out behind the seals, freed of the sliding pins, etc?

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[Major Doss]

Keith has it spot on again.

Strip it, get a trusted car/bike garage, engineers, someone clever to blow your pistons out, do not use pliers unless of the internal variety specific to brake piston removal (these are shit, anyway). I have dedicated piston pullers, but even these have had only limited success on cacked calipers. Not worth the dosh, for a one off.

I may be going against the grain on this forum, but use red rubber grease when installing your NEW seals, as brake fluid is hygroscopic, why attract moisture to where you least want it..? Get the braided hose, works wonders on shite brakes (like mine, which are now awesome). Clean, clean, clean. You may find the need for a bit of a rub down and a blow over. You will be amazed. Take your time, and enjoy it, don't break out heavy tools and check the many videos on youtube.

As amazed as I was when Itchy posted the above re; bleeding, and did not once mention China or HK! Good advice, there.

[davebike]

The calliper rebuild cannot here but you said it at the start :=

[steveh]

[FlightRisk]

[FlightRisk]

[MCN.]

Or as I once saw, drill through from the back of the caliper so you can drift the piston out, then tap the hole so you can stick a bolt in the caliper (with a copper washer under it mind you). Sickening

[Dalemac]

[RhynoCZ]

I might be late, but I had a chance to experience the difference between OEM brake hose and the braided one on a 98 CB500 (Brembo calipers on both wheels) and I say braided hoses are overrated, at least on that bike. The performance was worse, the lever got far too hard to be used sensibly and it gave you no real control of the brake.

If you want a ''proper front brake'' take MC and caliper from a sportbike, although I think the OEM caliper and MC on the CB500 is sufficient enough. Also having progressive springs will also increase the front brake performance.

It all comes down to your personal feel and taste.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[FlightRisk]

[FlightRisk]

[Taught2BCauti...]

Try gripping the brake hose tightly with one hand, whilst applying the brake with the other. If you can feel the hose swelling, you will definitely benefit from fitting braided hoses.
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[Kickstart]

[matto]

Any chance that the brake lever has been bent a little towards the bar? Is it roughly the same distance away as the clutch?

The reasons for these question is my own experience with this problem a few months ago when a re-build kit and braided lines failed to completely fix a problem caused by a subtly bent lever.

[Pete.]

[Dalemac]

[Kickstart]

Hi

While I can see where Pete is coming from, someone drilling and tapping a hole in the middle of an unsupported flat plane of a thickness I am unsure about (thinned even more to provide a smooth surface to seal the join) would worry me.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[Pete.]

[stirlinggaz]

[MattEMulsion]

How bad is the travel on your front brake in real terms? In my experience some are much sharper than others. For example the one on my R6 with standard lines is really sharp with little travel, where as the one on my missus's Hornet travels a proportion further and that is with braided hoses too. All of the brakes are in tip top condition, good pads, fluid changed, all cleaned and lubed etc - it just seems to be the way that they are.
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Yamaha YZF-R6