brake fluid

[eboos]

Has anyone had fluid boiling issues on a bike around here?

I haven't, but I've been using "good" stuff. $10.00 more per bottle seemed like cheap insurance to prevent problems. I did have brake issues this year, but that was due to a very flexy master cylinder, and crap pads. With both corrected, no issue with brakes.

[Expat]

My point is, the fluid is fine, from the replies so far, seals, (which should always be checked!) and "crap pads" (which IMHO are more critical than the fluid) have been the cause of the issue...

[eboos]

Loudon probably isn't the best track for evaluating brake fluids. There are only 2 heavy braking areas (or maybe 1 depending on who you are talking to). That, and how short our races are don't challenge the fluid as much as a different track would.

Then there is brake configurations to take into consideration and total weight of rider and bike. I was trying to stop a 650lbs total package with a single brake disk. This probably stressed the fluid somewhat, but I never had boiling issues.

The pads were certainly more important, as well as seals, but with both of them good, why not finish a proper package with good quality fluid.

[fjrrider RI]

Change it every 2 years, 5,000 miles or even more often, depending on use and temperature swings.
I do mine once every year on any bike that hits the track and every 2 years on bikes that are street only.

Thanks now I know why I blew my brake ABS system after 6 years

[Expat]

Loudon probably isn't the best track for evaluating brake fluids. There are only 2 heavy braking areas (or maybe 1 depending on who you are talking to). That, and how short our races are don't challenge the fluid as much as a different track would.

Then there is brake configurations to take into consideration and total weight of rider and bike. I was trying to stop a 650lbs total package with a single brake disk. This probably stressed the fluid somewhat, but I never had boiling issues.

The pads were certainly more important, as well as seals, but with both of them good, why not finish a proper package with good quality fluid.

Like I said, "devils advocate" however, people spend extra on the fluid then skimp on maintenance like seals and use "crap" pads. I would spend the extra on the pads every day!

[eboos]

Like I said, "devils advocate" however, people spend extra on the fluid then skimp on maintenance like seals and use "crap" pads. I would spend the extra on the pads every day!

The crap pads for me wasn't a skimping thing, just a bad choice, but I know and agree with what you are saying.

[fjrrider RI]

Is NAPA'S brand of brake fluid Johnsen dot4 any good? How would it rate?

[Doc]

Loudon probably isn't the best track for evaluating brake fluids. There are only 2 heavy braking areas (or maybe 1 depending on who you are talking to). That, and how short our races are don't challenge the fluid as much as a different track would.

Then there is brake configurations to take into consideration and total weight of rider and bike. I was trying to stop a 650lbs total package with a single brake disk. This probably stressed the fluid somewhat, but I never had boiling issues.

The pads were certainly more important, as well as seals, but with both of them good, why not finish a proper package with good quality fluid.

1, and 3 maybe 6... I must be doing something wrong.

[eboos]

I just wouldn't count 6 as a heavy braking area. No gear changes, just an adjustment in speed.

[Doc]

I just wouldn't count 6 as a heavy braking area. No gear changes, just an adjustment in speed.

Good point.

[Pittenger5]

1, and 3 maybe 6... I must be doing something wrong.

You need to carry more corner speed

[keeena]

Playing devils advocate, what makes one fluid better than the other?
Has anyone had fluid boiling issues on a bike around here?

Last few TDs I noticed brake fade near the end of my sessions; lever would almost come to the bar. The fluid was Prestone DOT4. After 40 minutes in between sessions, the lever would return to normal feel & travel. I just replaced with Motul RBF; will see how it goes at my next TD.

I assumed the sponginess was because the fluid was getting pretty hot. But its possible I had a little air in the system which wasn't noticeable when cool. Either way, I agree w/ others that said its cheap insurance. I was able to do a full bleed with empty lines/calipers/master using 3 reservoirs of fluid...about $6 worth of RBF; a $20 bottle should easily last a year. That's peanuts.

[Jim]

Last few TDs I noticed brake fade near the end of my sessions; lever would almost come to the bar. The fluid was Prestone DOT4. After 40 minutes in between sessions, the lever would return to normal feel & travel. I just replaced with Motul RBF; will see how it goes at my next TD.

i get brake fade near the end of every session. not to the point where the lever hits the bar, but i can feel it. i'm using Brembo high boiling temp fluid & it wont change anything. only solution really is to get a lever that you can reach the adjuster on the fly

[FireboltEric_MA]

I just wouldn't count 6 as a heavy braking area. No gear changes, just an adjustment in speed.

Go Faster

["Dangerous" Dan K]

i get brake fade near the end of every session. not to the point where the lever hits the bar, but i can feel it. i'm using Brembo high boiling temp fluid & it wont change anything. only solution really is to get a lever that you can reach the adjuster on the fly

[FireboltEric_MA]

[eboos]

Go Faster

Starting tomorrow, that won't be a problem.

[FireboltEric_MA]

Your Quitting?

[Kitt]

I just wouldn't count 6 as a heavy braking area. No gear changes, just an adjustment in speed.

I drop from 4th to 3rd, and in pics of most guys, their front ends are always slammed coming into the bowl.

I think Loudon is as good as any for evaluating brakes (but I think it's being wayyy overthought), as there's lots of trail braking and not many long periods with no brakes at all.

[eboos]

Your Quitting?

[CBR929RE]

Last few TDs I noticed brake fade near the end of my sessions; lever would almost come to the bar. The fluid was Prestone DOT4. After 40 minutes in between sessions, the lever would return to normal feel & travel. I just replaced with Motul RBF; will see how it goes at my next TD.

I assumed the sponginess was because the fluid was getting pretty hot. But its possible I had a little air in the system which wasn't noticeable when cool. Either way, I agree w/ others that said its cheap insurance. I was able to do a full bleed with empty lines/calipers/master using 3 reservoirs of fluid...about $6 worth of RBF; a $20 bottle should easily last a year. That's peanuts.

cooler ambient temps will also help because it will allow the fluid to cool even more between sessions.

I drop from 4th to 3rd, and in pics of most guys, their front ends are always slammed coming into the bowl.

I think Loudon is as good as any for evaluating brakes (but I think it's being wayyy overthought), as there's lots of trail braking and not many long periods with no brakes at all.

I must be way too slow because I don't use my brakes all that much really. 1 (I brake way too early), 3, 6, maybe a graze in 9, 11 but not hard and I think a bit at 12. everywhere else I'm completely off them.

[Chippertheripper]

Your Quitting?

i loled.
erik's brake problems stem from him dragging them. ALL the time.
and whatchu gonna rip tomorrow, mr man?

[eboos]

erik's brake problems stem from him dragging them.

Hey Chip, I think your motor's making noises. Better get that checked out.

[rice_rocket]

Just thought I'd put a quick post.

I've used ATE super blue and super red fluid on and off for cars over the years. It's DOT4 which is most compatible with everything. I'm about to flush my Subaru this year with it, and I got it at a price of $15 a bottle plus shipping. I am pretty sure I will have extra, so I'm going to put it into the bike most likely... never raced a bike, so I can't comment on it, but racing the car it worked pretty darned well.

Also to note about mixing fluid. I would personally fill with crap fluid, but DOT4, and then fill it with the blue stuff. The key is that it's BLUE.. so when you have flushed the system, the blue will be coming through nice and colorful, and then I'd put a little more in to finish it off.

Next time, buy the super RED stuff.. and you can see blue turn to red, and when it's all pure red, you're done bleeding.

One can is more than enough to push through a motorcycle probably 5 times over, so why not? If you're so concerned about it, I would buy even more expensive stuff.

I can't find the article here now though, but the gist was before: The more expensive "race" fluids actually suck up more water than the regular OEM fluids. So... if you're putting a lot of the fancy brake fluids, be prepared to change the fluids more often.

On my car I would probably do it 2X a year just to be safe, having a mightyvac is awesome.. that or always have a few beers to get someone to step on the brake. Even though I used speed bleeders too, in the end I always got someone to pump the pedal before I was done.

[UngaWunga]

I used Castrol 5.1 fluid in all my bikes. Good stuff and cheap compared to the $40/bottle for the baby seal squeezings y'all are using.