Can somebody on here talk me through brake fluid change thanks

bimota

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Right guys,
i have the brake fluid changed regular when the bike is in for a service, i have a gen 1 and know how to cycle the abs pump, BUT feed
up of taking the bike and paying to have this done, i can do a bit of maintaince as i have the front end off in my garage as the forks been sent away,
but would love to do the fluid change myself from now on so i can also cycle the pump more to.
So at the mo, please talk me through from start to finish how to change the fluid and on my own should i buy any bits that,ll help me, i have a rough idea but want to know exactly lol i know you guys do this blind folded

rob
 

bimota

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the vacuum pump above i got coming, is it a question of, connect it to the front caliper bleed nipple, open up the lid on the resouviour, open the bleed nipple, then pump away keeping an eye on the master cyclinder once the fluid gets low close the nipple fill the resouviour up again , open the nipple and carry on pumping, till you see clear then close nipple move to the other side

cheers

rob
 

bimota

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this video below. when he takes the lid off he sucks all the fluid out with a syringe, i thought wow never saw that done before thats how to get air in quickly i thought you pumped away and keep topping up surely that doesn, make sence

robt
 
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WJBertrand

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I noticed you said the front end was off. I don’t think I would try bleeding the brakes unless the calipers were mounted with the brake disk in place between the pads. There’s a chance to push the pistons out of the calipers otherwise.


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bimota

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I noticed you said the front end was off. I don’t think I would try bleeding the brakes unless the calipers were mounted with the brake disk in place between the pads. There’s a chance to push the pistons out of the calipers otherwise.


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it is off, but when i get the forks back i want to start bleeding my self not take it to mechanic this is why i,m asking cheers

rob
 

Sierra1

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this video below. when he takes the lid off he sucks all the fluid out with a syringe, i thought wow never saw that done before thats how to get air in quickly i thought you pumped away and keep topping up surely that doesn, make sence

robt
Harbor Freight has a vacuum thingy majig that sucks the fluid out through the bleeder. Still have to keep an eye on the reservoir. Just like the "normal" way, but you don't have to pump the pedal/lever. I have one but haven't used it yet.

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MattR

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Vacuum pumps are good for emptying the reservoirs and dragging the old fluid out but be warned, when the bleed nipple is slackened off, it can pull air in through the threads and make it look like you have air in the system. So I either wrap some plumbers ptfe tape round the threads to keep it sealed, or finish the bleeding in the normal way without using the vacuum


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bimota

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Mityvac MV8000 Professional... https://www.amazon.co.uk/dp/B00265M9SS?ref=ppx_pop_mob_ap_share

This is what I use. Similar type of thing


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if you don,t use a vacuum and you pump the lever, you still slacken the bleed screw off matt, the mechanic puts a hose on the bleed nipple and hose in a jar when your bleeding normal way still slackens the bleed screw off not heard of or had any issues there am i missing something

rob
 

tntmo

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I always start by using a syringe to remove the old fluid from the reservoir, no reason to start the process by pushing that old stuff through the system. I add fresh fluid before I pump the brakes, then just bleed manually. I have the vacuum pump deal, but I've accidentally emptied the reservoir too many times like that so I don't do it often unless I have a system that's giving me issues. Of course you have to cycle the ABS pump, it's not too difficult.
 

bimota

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I always start by using a syringe to remove the old fluid from the reservoir, no reason to start the process by pushing that old stuff through the system. I add fresh fluid before I pump the brakes, then just bleed manually. I have the vacuum pump deal, but I've accidentally emptied the reservoir too many times like that so I don't do it often unless I have a system that's giving me issues. Of course you have to cycle the ABS pump, it's not too difficult.
can you talk me through the none vacuum job then about the pumping the lever and opening the bleed nipple

rob
 

bimota

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i got all the time in the world to do it as i,m retired but just want to do it myself as i want to change more often and cycle the pump myself,
so i can do manual if thats easier for me as a novice can you just explain the correct manual way

cheers

rob
 

Saint rob

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if you don,t use a vacuum and you pump the lever, you still slacken the bleed screw off matt, the mechanic puts a hose on the bleed nipple and hose in a jar when your bleeding normal way still slackens the bleed screw off not heard of or had any issues there am i missing something

rob
I always remove the brake fluid from the reservoir first and clean the inside before refilling with fresh fluid. Be careful not to pull the lever when the reservoir is empty and before refilling with fresh fluid.
You then need to ensure that the end of the tube is always submerged in brake fluid Rob, then open the nipple and pump away (whilst maintaining the level in the reservoir) If the tube is not submerged you will draw air back into the system though.
I then finish it off by closing the nipple and give the lever a couple of pumps and hold it in whilst simultaneously releasing the nipple, you will feel the lever pull straight back to the handlebars, hold it there and tighten the bleed nipple before releasing the lever. I usually do this 5 or six times, then activate the ABS and bleed again.
Start with the left hand calliper and when done switch to the right hand calliper to repeat the process.
 
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I have always used a Vacuum pump like shown above. You do need to take the bleeders out and wrap a little bit of teflon tape as mentioned above. It's nice to have a helper put their finger over the bleeder hole in the caliper while you are getting the tape on and keep the lid on the reservoir as well. Wrap the caliper so no fluid gets on the pads or painted parts. Do this once and you are set. I put the pump on and pump it up to about -20 psi and then crack the nipple. Keep a close eye on the reservoir or you will suck wind and have to start over. Once again a helper's set of eyes may be good here. This is ESPECIALLY true with that forsaken tiny-ass clutch reservoir.
And good Dot 4 is fine unless you are doing track days. Just get lots of rags and keep everything covered up,
 
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