I have read all the posts and tried pretty much everything, although I don't have a vacuum pump. Used the syringe from the bottom, took the master cylinder off the handlebars, tied the lever back over night etc etc. and still getting bubbles of air. I have done the radial calliper conversion so they are 08 calipers on my 99. Pulled the calipers down, had the calipers hydrablasted, then new seals. New Venhill brake lines, new banjo bolts, new pressure washers etc. Where else can air be trapped? Been trying for 3 days now! I'd take it to the bike place if I could, but I would be pushing my luck getting there with just a back brake - pretty tempting tho cos its really pissing me off! I am only bleeding one caliper at a time, so is it possible that air can travel up one line then back down the other when I change over? Both calipers are independently hosed back to the master cylinder, not the crossover system. Can you bleed both calipers at the same time? Would that help?
Any ideas?
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Sounds like you drained the whole system. As such you can try and bleed the system all day via the bleed nipples and get nowhere. You also need to crack open the banjo bolt on the side of the master cylinder and bleed the air off the top of the main flexible brake line. Same applies when bleeding the clutch. Same method as usual, hold brake lever in and briefly loosen banjo bolt. You will see and here the air escaping. Bleed nipples are only of value when the majority of air has been purged from the system. Have a blast, Paul.
Thanks fellas, I'll give it another go.
Otherwise no Busa to Phillip Island tomorrow and will have to go on the FJR which is not what its all about!
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It will work. Have plenty of clean cloth over the tank and cluster and rinse the whole lot off with fresh water when done. Turn the bars and lean the bike so as the banjo is near enough the highest point in the system. Paul.
Done and dusted!
Thanks fellas.
It seems that there was air still trapped exactly where you said, at the master cylinder banjo. I thought I had bled it OK, but when I tried again there was still plenty there. As soon as I bled that banjo again I pretty much got pressure straight away. I think the other mistake I made was topping up the reservoir with fluid collected from bleeding because when you look closely this used fluid is still aerated with minute bubbles. It seems to take some time to settle out. So I was actually topping up the reservoir with aerated fluid?
I bought a pair of speed bleeders which have a spring loaded non-return valve set up. They eventually worked really well, but weren't much use to start with.
Sure is pretty quirky compared to car brakes. I bleed my daughters race car brakes sometimes 5 times a day, so as to get rid of the overheated/dirty fluid before each race so got a reasonable idea, or so I thought!
Pretty sure they will need re-bleeding again after a run so I am hoping the speed bleeders will make this easy to do.
Thanks again!
yea the stock master cyl are shit to bleed.
you just got to keep going through the motions until its comes good. and then repeat the following few days!!!!
yea there that bad!
I put a set of brembo master cyl on my gen 2 and so easy to bleed up as there is a nipple at the cyl it self.
takes the piss out of the stock set up really.......
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if master cylinder was emptied bleed it first.if you get a half decent lever and tried every thing else cable tie lever over night.also make sure caliper pistons are moving freely