So any ill effects of using dot 5 brake fluid. I went to the Yamaha dealership where i bought my bike and ask for dot 4 they didn't have any but they had dot 5. i asked if its ok to use dot 5 inplace of dot 4. so I bought it. Now i'm debated wheater to change it back to dot 4. Didn't notice any difference but i'm worried it will screw up some of the seals on the calipers. Any ideas.

Don't do it! You must flush the entire system with alcohol and even then you could have seal problems.


http://en.wikipedia.org/wiki/DOT_5

From what I know, DOT 5 is NOT compatible with DOT 3/4. You must get every bit of the old DOT 4 out of the system or very bad things can happen. DO NOT ride the bike until you get this sorted out! If it were me, I'd be pulling all brake lines and replacing with stainless. That way, there is no chance of a reaction. If you already have stainless and don't want to replace your lines, you will need to flush the entire system. I'm not sure the safest way to do this but you must do it the proper way or you will have problems. I'd be getting some professional advice if I were you and I'd avoid the dealership at all cost based on the info they provided.

Mark
99 R1

Is it dot 5 or dot 5.1? If it's dot 5 and you've put it in your bike, it's brakes are fooked. Dot 5.1 will work with dot 3 and dot 4, but dot 5 won't.

wow. What i did is drained the Dot4 then added the Dot5 and just bleed the brakes until all the dot 4 was out and all that was left coming out is dot 5. I may take everything apart and clean with brake cleaner and reassemble and add the dot 4 back and just chunk the dot 5 at the dealer ship. what a tool over there i asked if it is compatible with dot 4 and he said "oh yeah the mix fine" dayum I am never going back there again. thanks.

wow. What i did is drained the Dot4 then added the Dot5 and just bleed the brakes until all the dot 4 was out and all that was left coming out is dot 5. I may take everything apart and clean with brake cleaner and reassemble and add the dot 4 back and just chunk the dot 5 at the dealer ship. what a tool over there i asked if it is compatible with dot 4 and he said "oh yeah the mix fine" dayum I am never going back there again. thanks.

Are you sure it's DOT 5 and not DOT 5.1?

Like someone else said, DOT 5.1 IS compatible with DOT 3 or 4, but DOT 5 is NOT.

If you've already put the DOT 5 in, remove it and flush your system with rubbing alcohol. Then you can use the DOT 5 if you want to, but it will probably have a spongier feel than DOT 4 (DOT 5 is silicone). IF you do use the DOT 5, be sure to get ALL the old stuff out of EVERY part of your brake system.

DOT 5 does have its advantages, including the fact that it is non-hygroscopic, and will not damage paint or plastic finishes. Also, it is more stable in extreme temps (according to Wikipedia).


Let us know how it turns out.

Its dot 5 and it does feel spongier on not really liking it to much. i guess I'll drain it and clean the entire system. and refill with dot 4. thanks for the help.

learned something new today. Thanks.

I put dot 5 in my bike back in january after i did the ss brake line install and have had NO problems at all. although in the bleeding it flushed out alot of brake fluid.

It says dot 5 and not dot 5.1

again i have had NO seal problems, the brakes work mint and i plan on using the same fluid for the rear next season when i flush all my fluids.

it wont happen streight away R1slowflyer, it will happen over time

well in that case a full flush is in order...

I do know that i flush the system out 3 times during the install.

if in fact it is an issue than i guess i already did the damage.

:dunno

lol, just keep an eye on it ;)

:thumbup

damn i used dot 5 also when the dealer said it was ok as long as flushed the entire system first. hmmmmm maybe should switch it but problem was couldnt find 4 at the time anywhere

oh i finally checked the other day and guess what

dot 5.1 baby

i was really starting to worry for a bit there...

bump for lots of good info.

I ran that 5.0 with zero issues as far as seals go. Only thing was the brakes felt spongy. I would have switched back to 4 but bike has been sold.

Yea I don't know why the named dot 5.1 the way they did. It only causes confusion.
Lesson you cant trust the parts guys at the dealership.

Sent from Motorcycle.com App (http://www.motorcycle.com/mobile)

DOT 5 is a silicone-based brake fluid (contains at least 70% by weight of a diorgano polysiloxane). Unlike polyethylene glycol based fluids, it is hydrophobic. DOT 5.1, like DOT 3 and DOT 4, is a polyethylene glycol-based fluid (contrasted with DOT 5 which is silicone-based). Polyethylene glycol fluids are hygroscopic and will absorb water from the atmosphere, which is necessary to prevent sheer and undiluted water in the braking system, which is very corrosive. Also, water droplets can freeze in the pipes, thus blocking the system.

Glycol based fluid absorbs moisture, and disperses the moisture throughout the system and contains corrosion inhibitors. Silicone fluid does not allow moisture to enter the system, but does not disperse any that is already there, either. A system filled from dry with silicone fluid does not require the fluid to be changed at intervals, only when the system has been disturbed for a component repair or renewal. The United States armed forces have standardised on silicone brake fluid since the 1990s. Silicone fluid is used extensively in cold climate, particularly in Russia and Finland.

With DOT 3, DOT 4 and DOT 5.1, moisture diffuses into the fluid through brake hoses and rubber seals and, eventually, the fluid will have to be replaced when the water content becomes too high. Because Silicone brake fluid does not absorb and disperse water throughout a brake system, if water does enter the system, (as in the system being disturbed for a component repair) the system can have pockets, or sections of corrosive moisture. Once moisture enters a silicone based brake system, corrosion is inevitable, although if the system is "not" disturbed, the system can go many years without service.



I'll stick with DOT 4