Changing the brake fluid on a Yamaha YN50 2T

I want to replace my front brake caliper because one of the pistons is stuck and there are visible signs of heavy corrosion on both the pistons.
I toyed with idea of just changing the pistons and seals but worked out that there isn´t much price difference in changing the whole unit.

In doing this I want to change the brake fluid, I´ve learned that over time the heat generated by the friction of the brake pads on the brake disc, will burn the fluid.

My question is, how should I go about this?
I believe that when replacing the fluid it has to be done under a certain pressure.

If anyone has tried it, on a Yamaha or any other scooter, then I´d be grateful for any advice.

It´ll cost me about 30 quid for a garage to do it and the procedure apparently takes about 15mins.
I´d prefer to do it myself, to learn something new and save some money.

Cheers

 

All you need is a vacuum bleeder. £10 - 20 on ebay.

Connect your brake system back up and add some fluid to the master cylinder if needed. It's always easier to have someone else keep topping up the fluid. Connect the pipe from the vacuum bleeder (having read how to use it in the instructions!) to the bleed nipple on the caliper. Open the bleed nipple, let air then eventually fluid be drawn out under vacuum. Keep the master cylinder topped up all the time. Close the nipple. Open the nipple and repeat the process several times until the fluid comes out with no air bubbles in the tube to the vacuum pump at all. Finally tighten the nipple, remover the vacuum pump.

Job done.

 

Hi Gemma,
thanks for getting back to me so quickly.
I checked out the options on ebay and found quite a few relevant products I could use. Brilliant.

I actually went round to the Yamaha service center (I know them quite well now) and managed to get permission to do as much of the work I could (thus saving them time and me money).
The actual process of changing the fluid was done by a great mechanic called Steen.
I watched him carefully as he did it and basically learned exactly how it should be done.
I ended up paying 13quid for his time (it´s normally 55 quid an hour ) and a pittance for the fresh fluid and copper washers that he had to change.

Next time it needs to be done, I´ll do it myself.
I must admit he was a bit surprised when I saw the old fluid...it was BLACK.
I bought the scooter used 6months ago but I´ve done roughly 6000km on it so the fluid might not have been changed for possibly 10,000km.
I´m not sure when it should be changed as a rule, but I´ll keep an eye on it every 1000km to see when it starts to go brownish.

Thanks again for your sound advice,

Jools

 

Great to hear you are sorted! Best way, watch someone do it, then next time...

I change the fluid once a year on my bike, but it's probably more than really needed. Don't take long though with the vacuum bleeder.

 

When you say you change it once a year, what kind of milage are we talking about?

 

Depends, these days not that many miles at all. At one time around 100K! You should have recommendations in your owners manual, hard town riding makes a huge difference, compared to some leisurely cruising, so they generally recommend changing sooner in harsh conditions. Whatever the mileage you should change it at least every other year.