Mityvac

[John712]

Pros and Cons.??

I just did a complete drain of fluid, new master cylinder, new SS brake lines, took the calipers apart (split in half) and claened the shit out of them. See thread if you haven't already ---> http://sportbikeaddicts.com/forums/s...ead.php?t=6792

I have the entire braking system together, poured fluid in, started to use the Mityvac. Sure it sucked the fluid through the lines faster then pumping the lever. But I kept getting air bubbles coming from the bleeder valve into the hose. I went through 3 Brake fluids only because I didn't want to use it again. I want everything NEW.

I was dumb founded, I checked the torque specs on the banjo bolts and they were fine, then checked the 4 bolts on each caliper that are there to hold them together and they were fine. So in a panic distress I made a call to a good mechanic, you may know him, his name is Joe from sportbikeaddicts.com and he told me it's sucking air from the bleeder valve threads and to try bleeding them the old fashion way.

Well 10 minutes later no air bubbles and i was done Does anyone else use the mityvac to bleed brakes, or do you use it just to suck the fluid through the system faster then do the old fashion bleed.?

[Jimmy]

Just use it to change the fluid. Bleed them the normal way.

[IrocRob]

I don't use a mityvac at all, for anything.

Did you pre-fill the calipers before you put the pistons back in?

[GinoE]

my 1st time using the mityvac & yeah, i saw the same bubbles - i ignored them (after re-filling the reservoir 3x each caliper). the brake lever was hard when i applied it (and the bike did stop).

guess i'll have to revisit my brake job & bleed them as suggested here.

[CBRBob]

I use a Mitivac or an air operated one to flush the fluid or pull fluid through with new lines etc. I always finish with the old pump the lever/pedal and bleed.

[John712]

Originally Posted by CBRBob

I use a Mitivac or an air operated one to flush the fluid or pull fluid through with new lines etc. I always finish with the old pump the lever/pedal and bleed.

This is what I will do for now on, after so many track days, do a complete tear down and cleaning and use the mityvac to draw the fluid through the lines

Originally Posted by ginoe

guess i'll have to revisit my brake job & bleed them as suggested here.

I would, my brake lever was spongy before bleeding the old fashion way.

Originally Posted by IrocRob

Did you pre-fill the calipers before you put the pistons back in?

I poured a little into the jets inside the caliper but it only came out when putting them back together. After calling Ron, it wasn't really suggested to do it.

Originally Posted by Jimmy

Just use it to change the fluid. Bleed them the normal way.

That's what I wound up doing. And I'm sure the whole job was done in half the time as if I were to do it by pumping the brake lever over and over.

[Jon FZ1]

Guess where he air bubbles usually come from when using the Mityvac...... they are coming from the threads for the bleeder itself.

[Cakes206]

Originally Posted by Jon FZ1

Guess where he air bubbles usually come from when using the Mityvac...... they are coming from the threads for the bleeder itself.

This happened to me a couple weeks ago...then when I would put the lil rubber caps on the bleeder, fluid was seeping out from the base of the threads...drove me nuts