Bleeding front brakes question from a noob

Hi all

Going to be changing my front pads on my K7 SV650S, and will need to replace the brake fluid after new pads are fitted...colour of the fluid in the reservoir indicates it needs a change. Have searched a bit but cant find the answers to my questions.

I checked the manual and it shows how to replace the fluid...but some questions, as I have not done this before:

1. It says keep the bike level...huh? With the std kickstand it comes with...now how must I do that - balance the bike and change the fluid at the same time? WTF?
2. It states to suck out the old liquid from the reservoir, and then bleed the brakes while topping up the reservoir. Wont the old and new brake fluid mix then?
3. I see both 2 front brake calipers have bleed nipples, does this mean I have to bleed the right caliper and then the left caliper after? So I have to bleed the brakes twice essentially?
4. The tutorials I have seen on YouTube, most guys use the tube and bottle trick...is it good enough or should I save the hassle and buy a bleeding vacuum kit?

Cheers

[NTECUK]

Paddock stand. They are so handy.
Keeping the bike upright and level
Less likely to suck air in the system.

Also look up reverse bleeding with a syring.

Vac bleeder you can DIY one from a vacuum cleaner .
Have a Google

[johnnyrod]

You can do it on the sidestand, and if it's just a flush out then it's quick and easy. Yes the fluid mixes a bit but don't worry. Turn the bars left, the right caliper nipple should be at the high point, attach your tubing and make sure the nipple actually turns (maybe use a socket first to crack it). top off reservoir, open the nipple a little, and pump the brake lever. If you open it too far it'll tend to suck back. When the level drops near the outlet of the reservoir, top it up and keep going until the good stuff comes out the bottom. When it is clean, do the thing of slowly squeezing the lever while closing off the nipple, so fluid is coming out slowly while you close it i.e. no air is sucking back. Next put bars to full right lock (cap the reservoir for this if you want) and repeat on the left side. Once you're done put a bit of fluid in the top so it's mostly full. As long as it doesn't run dry while you're flushing, you'll be fine. I've never used a vacuum bleeder in 25 years, they're really only useful if the master cylinder is totally dry, but you can work without one then anyway.

[Blapper]

+1 for reverse filling. Cheapest and easiest and foolproof providing you can get a LARGE enough syringe.

Once you've finished cable-tie the brake lever to the bars (ie. brake on full) and leave it overnight to remove any stray bubbles of air

[johnnyrod]

Can do - leave it on full left lock i.e. the master cylinder banjo bolt is pointing bolt-head down, so the bubbles collect at the m/cyl end. When you release the cable tie they'll suck into the reservoir. It also pushes the brake pistons out for a long time, so if they have been sitting back a bit in the calipers (which causes excess travel) then they'll get used to being in the right place.

[R1ffR4ff]

1:If you don't have a paddock stand you can get the bike up closer to vertical by putting a piece of thick wood under the side-stand but do this only of firm level ground(Concrete/Tarmac drive etc).Don't make it too thick for obvious reasons as you don't want the bike to go over.

If you have a garage you can use a ratchet lock strap to secure the bike to something.

I use,"Old School" methods for bleeding my brakes once I have pumped all the old fluid out.

A piece of 6mm internal diameter tubing into a jar on the floor and the other end on the bleed nipple.
I quarter fill the jar with new or old brake fluid and make sure the pipe is the right length to go under the top of the fluid by cutting it to the length required.This acts as a one-way valve disallowing air to get back into the system whilst bleeding.




Open right hand bleed nipple.Top up the M/C(Master Cylinder)with new fluid.Watch the level whilst pumping the lever and when it drops about half way top-up the M/C and repeat until you see the fluid and air bubbles go into the jar.

If for some reason you cannot pump the fluid through it just means the MC needs priming.Easy trick to this.Spit on your hand and spread it around and place it on top of the MC and press hard to form a seal and pump the lever again.You should get fluid though.

When you are happy with no or few bubbles coming through into the fluid tighten the bleed nipple but just firmly,do not over-tighten.

Repeat bleed for left hand side.
Come back and do right and side
and then do the left again.

Doesn't take long when you get the hang of it and you don't have to change the fluid that often compared with other maintenance jobs.

Might Vacs are good but expensive and I've never needed one.A syringe and back filling is a good way to go if as above you can find the right one.

HTH

Tip:
You can use old supermarket plastic carrier bags to cover the paintwork and parts of the bike that might get fluid on them.This is worth doing as brake fluid is very corrosive.I keep my old brake fluid as a rust and paint remover for small parts.Just let the bits sit in them for a few days.

Also a 50/50 mix of Brake fluid and Acetone makes a great rust release fluid.Way better than WD40 or similar.

[NTECUK]

Amazon etc sell syringes.
The fact your doing it one off your ok with a normal one .
Sealy do one that is ok with the brake fluid on the seals
Sealey VS404 Oil & Brake Fluid Inspection Syringe 200ml

The old cylinder vac and two strok

e oil container vac bleeder

[shiftin_gear98]

Pretty sure this is the one I use.
http://www.ebay.co.uk/itm/Brake-Blee...f0HOyGJM_BB-0w

[SV650rules]

This company sells a non-return valve, wonder what their returns policy has to say about non-return stuff LOL - Also I often wonder if you should ever buy a battery that is shipped free of charge.

http://www.ebay.co.uk/itm/New-Motorc...3D161657955017

https://www.youtube.com/watch?v=1iSN2vc5-b0


The problem I see with reverse bleeding, especially on ABS systems is that dirty fluid from slave cylinders and lines is being forced back into the system not sucked out, there should be filters in ABS system and these could get blocked by crud, which in any case may be pushed back into system once brakes are used again. The dirtiest most contaminated fluid is likely to be in lower parts of system.

IMHO maybe a combination is best, get clean fluid into system by sucking from the bleed nipples on calipers (or squeezing brake lever / undo nipple etc, or with non-return valve as in link above) and then use reverse bleeding as a more effective way of getting any remaining air bubbles out.

Getting air into an ABS system actuator is not normally good news as it can be devilish hard to get it out again.