bleeding brakes, fluid change

[Hoblick]

im undecided yet if im gonna go for all braided lines or stay stock yet.

but either way im gonna have to flush and bleed the lines

so give me some pointers.

i have a mityvac i picked up from harbor frieght.

and need to know the technique to use.. in some detailed instructions.

anytime before i have had all the trouble in the world doign them. and i want to bash something.

tonight i tried helping a friend get the pressure back in hydraulic clutch on his VFR, and no dice.

he disconnected the line to put new heli bars on, and then after that no pressure at all at the lever. i spent a good 2 hours with the mighty vac, and still couldnt get a lick of pressure at the lever. so its making me think twice about jumping into it on my bike for the brakes.

so please enlighten me.

[Earache]

Might Vac's kinda don't suck enough. Might try installing some speed bleeder valves to help you. They keep air from getting in by using a small one way valve. They're cheap and work well. Here's a picture of one so you can see how it works: http://images.google.com/imgres?imgurl=http://www.raceshopper.com/images/speed_bleeder2.gif&imgrefurl=http://www.raceshopper.com/speed_bleeders.shtml&usg=__hw35lbEY6mgNnnwMYcw1hHyJFi4=&h=320&w=460&sz=20&hl=en&start=1&sig2=O-gBZeESNaeJ3JvOwLWtdg&um=1&tbnid=cFDYmbMspIy-aM:&tbnh=89&tbnw=128&ei=tXY6ScqEF536NPX-nLoF&prev=/images%3Fq%3Dspeed%2Bbleeder%26um%3D1%26hl%3Den%26rls%3DHPIA,HPIA:2006-09,HPIA:en%26sa%3DN These will set you back around $12 each and are available through any bike shop via Tucker Rocky - Parts Unlimited, etc.

If you have access to compressed air, get a bleeder like this one:

http://www.sandhillspowersports.com/sandhills/OnlineStore.do?DSP=200&PCR=1:70000:70034&IID=sbs_bsbacc_06

Beats the shit out of a Mighty Vac and will bleed lines in about 2 minutes. I have this exact model and it works well. Snap-On and others make one just like it. They run about $200. Price on this webpage is obviously wrong - must be on sale for $175.00.

When bleeding lines, the air is usually trapped at 90 degree bends - such as where the banjo bolts attach to the master cylinder. Mighty Vac often don't have the pressure to clear these areas. Tapping the 90 bends lightly with a screwdriver handle or some hard plastic will sometimes help jar the air bubble loose. Or use a power bleeder and be done with it ina minute.

And if you're just changing fluid, don't drain the lines - just keep adding new fluid as you suck out the old and the fluid drained becomes clear. It's much harder to fill and bleed an empty line than it is to run fluid through it. You use a bit more fluid this way, but it is much easier.

Good luck!

Edited December 6, 2008 by Earache

[John]

the problem with the MC and taking forever to get fluid through is because the MC can not pump air. when this happens, you can loosen the brake line bolt at the MC, and pump till fluid squirts through, then tighten it back up and build up pressure at the lever. put a rag under there too, as brake fluid is nasty shit and will eat your paint.

ive used a mityvac with minimal problems before. speed bleeders are better, but the mityvac works well. \

and +1 to not draining the lines if you are just changing fluid.

if you are going to change pads and stuff too, i would resist the temptation to just pop in the new ones and go.

whenever i change pads, i like to take the caliper off, take the pistons out and clean everything up nice and shiny and regrease the sliding pins. polish the pistons to remove dirt that will cause leaking or binding.

it takes a little bit longer, but IMO brakes are very important, and its cheap insurance.

[The King]

Hell, I have been successful just pumping the lever. I use the MV now and it is a breeze.

To be honest, the first time I changed my lines I assumed the lines would be routed the same as the stock (1 line from the MC to one caliper then from one caliper to the other). In case you didn't know, each caliper gets its own dedicated brake line. I noticed a huge difference on my TLR.

[Hoblick]

Hell, I have been successful just pumping the lever. I use the MV now and it is a breeze.

To be honest, the first time I changed my lines I assumed the lines would be routed the same as the stock (1 line from the MC to one caliper then from one caliper to the other). In case you didn't know, each caliper gets its own dedicated brake line. I noticed a huge difference on my TLR.

depending on what kit you get.. a race line kit has each caliper its own dedicated line, but they do have a stock line setup as well.

thanks for the tips all. keep them coming