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hi on my 01 yz 250f i cant see any brake fluid in the front brake sight glass

so can i just unscrew the 2 screws on the master cylinder cover, take off the cover, and refill the brakes with dot 3 or 4 brake fluid and be done with it

how do i bleed the brakes properly because my front brake feels squishy

can i use auto brake fluid

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You realy should bleed all the old fluid out. Check out the TT tips for bleeding your brakes. You should bleed your system at least once a year. Use Dot 4, car, truck or bike its all the same. I would not recomend Dot 5 (its for high tech prure breed racing) unless you want to change it once a month. All brake fluid fails by heat and condinsation and Dot 5 is good for heat, but condinsation crystallizes into what looks like small little glass beads and dot 5 will not live as long as 3 & 4.

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I don't think MC brakes heat brake fluid like car brakes so DOT 3 would be OK.

The biggest contributor to brake fluid boiling is moisture in the system so frequent flushing is very important for fade resistance and to prevent corrosion damage.

I use ATE Super Blue Racing (DOT 4 from Bavarian Autosport (bavauto.com)) because I have it for my cars, and the blue color makes it easy to tell when all of the old fluid has been flushed out. The blue is also easier to see in the sight glass.

Next year I'll use a Super Gold.

If your brakes are mushy and you can't see fluid in the resorvoir here is a quick fix: Reposition the master cylinder on the bars until the cover is level, remove the cap and rubber dam from the resorvoir. Then use a screwdriver to pry the pad on the piston side of the caliper away from the rotor, this will backflush the system forcing the air back to the resorvoir. Top off the resorvoir and operate the handle to force the pad back to the rotor. Don't let the resorvoir get too low or you'll suck more into the system.

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i dont really understand what youre saying since i'am new to hydraulic disc brakes

is there any good thumpertalk instructions for this

can i just take of the master cylinder cover and pour some more fluid in

i thought the bleeder was on the actual brakes

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i dont really understand what youre saying since i'am new to hydraulic disc brakes

is there any good thumpertalk instructions for this

can i just take of the master cylinder cover and pour some more fluid in

i thought the bleeder was on the actual brakes

Yes, you take the master cylinder cover off and fill it to the top line on the sight glass.

Try pulling the brake lever in as far as you can, and tie it there with something. Leave it over night and sometimes it will help some.

You really do need to change the brake fluid completely if it hasn't been done recently. Do a search on the subject, there are probably 50+ threads on bleeding brakes.

Personally, I cheat and use a Mity Vac. Takes about 15 minutes to completely change out all the brake fluid in both front and rear brakes.

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i dont really understand what youre saying since i'am new to hydraulic disc brakes

is there any good thumpertalk instructions for this

can i just take of the master cylinder cover and pour some more fluid in

i thought the bleeder was on the actual brakes

You said the handle was mushy indicating air in the system.

Low fluid level would let air into the system, but it would be in the brake hose near the master cylinder, not down in the caliper. My suggestion was a quick method to get air out that got into the system because of a low resorvoir. By pushing the caliper piston back from the rotor fluid will be forced back to the resorvoir along with the air. topping off the resorvoir and pumping the brake handle will push the piston back to the rotor but without air.

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hi on my 01 yz 250f i cant see any brake fluid in the front brake sight glass

so can i just unscrew the 2 screws on the master cylinder cover, take off the cover, and refill the brakes with dot 3 or 4 brake fluid and be done with it

how do i bleed the brakes properly because my front brake feels squishy

can i use auto brake fluid

You'd best put back what kind of oil is specified on the master cylinder or manual .... I saw a guy once put his on brand back in and he had no brakes till he read what type was needed and when back to it...

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