dot 5 to dot 4

[trx450Rrider]

i need help! i changed my brake fluid and once i was done i looked at the bottle and it was dot five. i didnt ride. the next day i draing it out and put in dot 4 and i cant get the brakes to work now. i dont know whats wrong with them. ive been bleeding them for more than an hour. its the rear brakes. i just keep pumping and then crack the bolt and it comes shooting out then i shut it and pump some more. its not working

[MR.BIG]

Are you refilling the reservoir as you bleed them. You must have air in the line. You can try to gravity bleed them just crack the bleeder and let it trickle out. Are you sure you are bleeding them correctly.

you will need new brake system. your rubber expanded when you mixed dot 4 & dot 5. happened to me last year.

[2MuchChi450R]

Originally posted by MixMasterMike
you will need new brake system. your rubber expanded when you mixed dot 4 & dot 5. happened to me last year.

Ditto, you're going to need to replace all of the seals, caliper and master cylinder, and get a M.C. rebuild kit from your dealer. Then you'll need to flush everything out, I mean completely out. Just remember next time to triple check everything before putting it into or on your bike next time.

[BLAZE1]

Are you guys serious??
What is the difference between dot 4 & 5?
My brother & I just did his street bike & I thought we f***** something up because we bled the brakes for like two hours after changing to stainless lines and there was still no breaking power. We needed to prime the master cylider, which means either a vaccumm bleeder or a hell of a lot of manual labor. We ended up using a suction gun(like a super soaker but for auto fluids:D) to literally suck the fluid through the lines and out the calipers. once we did this we still had to bleed them regularly with another half a bottle of brake fluid to get the pressure all the way up.
I don't know if you just have air in the line or if there really is a chemical reaction when mixing dot 4 & 5, but the best of luck to you!
p.s. let us know what happens

[2MuchChi450R]

difference between dot 4 and dot 5:

Dot 4 is a petroleum based fluid

Dot 5 is a synthetic silicone based fluid

It's like mixing water and oil

[trx450Rrider]

what i did was i took out the dot 5 the next day andf didnt even rid the bike and i opened the bleeder and kept pressing the brake till nuthing came out. then i filled up the system with dot 4 and i kept pumping and stuff would come out when i cracked the bleeder and sometimes there was air spewing out and sometimes there wasnt. i hope its just air in the line because i dont think dot 5 could do that much damage in less than one day

[trx450Rrider]

o snap i bled the brakes like 3 minutes ago and they work. thanks for scaring the hell out of me and making my parents mad at me for screwing up another thing.
haha

your lucky you didnt ride it..i rode mine for like 2-3 days and then they strated to stop working and before you knew it the pedal would go really far down and nothing would happen...I bleed and bleed and nothing. Just bought a new system

[foolofsand]

actually dot 4 can also be a synthetic based fluid and the valvoline brand has it. it says it is completely compatable with other dot 3 and 4. when you mix the 2, it does seem to take longer to bleed and get to work, but it will work.once the fluids mix

[2MuchChi450R]

Originally posted by trx450Rrider
o snap i bled the brakes like 3 minutes ago and they work. thanks for scaring the hell out of me and making my parents mad at me for screwing up another thing.
haha

ROFL, sorry to scare ya kid. :D Just make sure you triple check everything from now on.