HELP struggleing bleeding Two line Venhil Braded Race Hoses

[seb421]

been at it all day, replaced the cush drive rubbers and sorted out the back now all neat and tidy like a new one, the old cush drive rubbers was shagged after the 20,000 miles and countless wheelies

fitted a two line braded brake line sytem on the front, can i bleed it....can i Fook!

i tried in vain four hours like my life depended on it... after dark i gave up!

what the hell am i doing wrong? do you need to do both nipples at the same time or somethig with a two line set up?

how many washes should be on the banjo's on the calipers first i tried two at the end then the banjo then another washer, bleeding with this didnt realy work...

then tried just one washer either side of the banjo.... nah nothing again!

all i got was a weeks worth of newspspers coverd in DOT 4 all over the floor.

now im not pants when it comes to bleeding, ive dont it countless times on the motocross bikes and ive also bled the original set up on the firestorm before....

so whats the deal with these two line race set ups! there is no leaks in the system but it just wont presurise at all wanted a ride today while it was remotley sunny here (bolton) but thats gone tits up and tommorw will be full of grandads, horses, plod and the odd boyracer on the wrong side of the road.

Please if you can help chip in with your info, i did a search btw but nothing on bleeding the two line showed up, just that it was hard the bleed the two line...

[Zakalwe]

OK, due to a botched attempt to fit Yamaha radial calipers on my blade, I am now an expert at bleeding brakes. :mad2 :mad2

Firstly, there should be a copper washer either side of each banjo (this means 3 washers at the master cylinder end- washer, banjo,washer,banjo, washer, and two at the caliper end- washer, banjo, washer).

Secondly, run the lines, tighten everything up, then bleed the master cylinder first. If you have a radial m/c then this is easy, as the cylinder has a bleed nipple. If you have a standard m/c, then just crack open the m/c banjo a tad, squeeze the lever, then tighten without releasing the lever. Repeat until fluid is being pushed out of the banjo. It helps if you rotate the m/c on the clipon until the banjo is at the highest point (keep an eye on the fluid reservoir though)......

Then move to the nearside caliper... crack the bleed nipple and bleed as normal (squeeze the lever, tighten the nipple, release the lever, crack the nipple and repeat).

Finally, the off-side caliper as above. Keep an eye on the fluid level as if you let it suck air, then you are back to square one.

Once you get pressure in the system, it can be worth tying the lever back to the bars, whipping the caliper off, crack the bleed nipple, then push the brake pads back with the bleed nipple held highest. Sometimes a bubble of air can get trapped behind a piston.

Finally, you will see some places recommending tying the lever back overnight with the resevoir cap off or loose. Please don't do this. Once the lever is pulled back, the master cylinder seals off the inlet port and the system from the m/c piston down is a closed system. By leaving the cap off or loose, all you are doing is allowing the fluid in the reservoir to absorb moisture from the air.

I always use the method above. I can probably bleed the blades system (2 line) in about 30 minutes....and that is starting with empty lines.

[Zakalwe]

Ohh.. and another thing...copper washers are crappy bits of shite. If you go to any place that does hydraulics, get some 3/8" dowty washers (these are steel with a rubber seal). Far better, they can be reused and they don't squash down like copper washers (which are single use only...throw them away after using them once.)

You can also pick them up on eBay...a pack of 10 should only be a few quid.

[sirch345]

+ 1 on the write up by Steve (Zakalwe) that's how I bleed mine too.

Steve,
Interesting about the use of Dowty washers

Chris.

[Zakalwe]

+ 1 on the write up by Steve (Zakalwe) that's how I bleed mine too.

Steve,
Interesting about the use of Dowty washers

Chris.

Thanks Chris....Dowty washers are far better as they dont squash down like copper washers. Having said that, the last time I did the brakes on the blade I had to use them as I had run out of Dowtys. The copper washers I had were very soft, and although they sealed OK, it felt like I was about to strip the threads in the caliper as the banjo wouldn't torque up (due to the copper squashing)

[Stratman]

copper washers (which are single use only...throw them away after using them once.)

Not really. Heat them with a blowtorch till cherry red then drop them in water and they will be re annealled and soft again.

Bleeding the hoses is a pain though and an alternative to the excellent method suggested is to use a vacuum pump.

[Zakalwe]

copper washers (which are single use only...throw them away after using them once.)

Not really. Heat them with a blowtorch till cherry red then drop them in water and they will be re annealled and soft again.

Bleeding the hoses is a pain though and an alternative to the excellent method suggested is to use a vacuum pump.

Yes they will be annealed, but once the banjo bolts have been tightened to the correct torque, the copper will be squashed (look at a washer when you take it off...you can see where it has distorted). Reusing them will make them thinner and thinner. For the sake of a couple of pence I would never reuse copper washers. It just aint worth it when you are dealing with brakes (especially not for pennies)...stick exactly to what the manufacturer says!

[Stratman]

It just aint worth it when you are dealing with brakes (especially not for pennies)...stick exactly to what the manufacturer says!

Honda also say that the caliper retaining bolts should be changed each time they are used but I never have in 9 years of ownership! Clean up the old ones and use Loctite.

[sirch345]

+ 1 on the write up by Steve (Zakalwe) that's how I bleed mine too.

Steve,
Interesting about the use of Dowty washers

Chris.

Thanks Chris....Dowty washers are far better as they dont squash down like copper washers. Having said that, the last time I did the brakes on the blade I had to use them as I had run out of Dowtys. The copper washers I had were very soft, and although they sealed OK, it felt like I was about to strip the threads in the caliper as the banjo wouldn't torque up (due to the copper squashing)

Steve, I appreciate the info on the Dowty washers. I've not experienced copper washers being that soft yet, but the Dowty washers certainly sound like a very good alternative

Chris.

[seb421]

thanks for the info guys, got the brakes sorted the day after the first post.

got a one way valve from halfords and stuck that on the nipple saved keep cracking it open and shut, there was so much air and sh1t trapped in the lines no wonder it was taking ages to bleed the old skool way.

ive used the washers as supllied but if i ever come to refit will use those other said ones.