XCSKIBUM

Well I never changed brake fluid in my 2006 Charger in the 5 years I raced it. I would think that braking a 4300# vehicle from 120+ MPH to a speed slow enough to make a "U" turn at the end of the 1/2 mile deceleration stretch would be considered "braking hard".




You might also note that when I was doing my "burnout" in the water box, I didn't have a "line lock" so those rear calipers are getting pretty hot even before they are pressed into service at the end of the pass.

HerrKaLeun

Brake fluid boiling points based on % water
I measure my water content before every oil change and as I get closer to 2% I have it flushed.

Many people smoked and didn't die, that doesn't mean smoking is healthy. You not crashing and killing yourself is anecdotal evidence. Every manufacturer, any car organization and agency and basically everyone with knowledge recommends replacing brake fluid. People going on serious track racing typically replace it after every race. they have speed-bleeders for just that reason
A guy at my work also didn't believe me. We checked his totally black fluid (it is clear when new!) and my moisture-meter couldn't even read it because his water-% was out of range. Yes there is a chance the dirt and corrosion doesn't literally fail the brakes, and there is a chance his brakes have enough thermal mass to not boil the fluid. But why take a chance to save $70 for a flush at the dealer? Just because he is still alive doesn't' mean not doing required brake service is a good idea.

Maybe this isn't as critical for bicycles (not sure about temps, though), but advocating to skip generally recommended brake service is not a good idea. Skip service on bearings, on everything else... all that does is brake your bicycle. But not servicing brakes?

sorry for going off-topic

XCSKIBUM

I'll bet you change your oil every 300 miles.

And BTW Toyota doesn't recommend brake fluid changes.

FrontRanger

+1 on these. Absurdly good performance/reliability for the price.

asmac

I have Shimano XTs and they are fantastic. A little more $ (USD150 for the pair at Chainreaction) but the average rating of 4.8/5 for 472 reviews says it all.

HerrKaLeun

Every 8-10K miles as the onboard computer tells me. Of course I could just skip that, because someone on the internet told me oil changes are a waste of money. And someone probably had a car for 50K miles before it was sold and never changed oil and didn't have a problem....

I once had a Buick and the service manager also told me they never change it. Doesn't' really matter what the car OEM says (in both my Mazda and Honda manual it says every 3 years), the fluid still is hygroscopic. Unless Toyota uses DOT 5 (silicone). Car manufacturer also are stingy with recommending much up to 5 years to keep the TCO low (as reported in Edmunds etc.). If it lasts beyond warranty they are OK.

I noticed on my Mazda that just had a normal cap with a hole over the reservoir, that after less than 2 years I got close to 2% water. As pads wear air is drawn into the reservoir and with it moisture. My Honda has a membrane to prevent direct contact with air and I get to over 3 years. I assume the engineers at Honda are just stupid and wasteful to add such features..... they should be more on the internet where the real knowledge is.

All the bicycle brake manufacturers (DOT or mineral oil) recommend fluid changes. Guess they also didn't get the knowledge from the Internet. Now I'm not sure how well sealed the bicycle brake system is, and it probably depends on the price and manufacturer. But dirt also gets around the seals. Nothing is 100% sealed, and water (and oxygen etc,) also permeate plastic and rubber. You may think your system is tight, but it isn't. Can you stretch maintenance a bit if you don't ride in adverse conditions, sure. But skip entirely?

gsa103

Apples & oranges. Most bike brake systems run silicone based DOT 5.1 while most cars are DOT 4.
The DOT systems are notorious for squealing if they aren't bleed on a regular basis (google "Avid turkey warble"). Supposedly the new SRAM Guide brakes are much better, but they don't have a long-term track record yet to see how they really handle irregular maintenance.

XCSKIBUM

I appreciate all the input and although the Shimano Deore brakes seemed to be a good choice, I found a good deal on a complete It showed up on E-bay last night for just under $78 including shipping.

Since the bike in question has SRAM X-7 shifters/derailleurs and is a light weight XC set up that won't be used for anything but moderate trail riding, the SRAM system seemed to be a good match. I researched the bleed procedure and found it to be a pretty straight forward operation. I also don't have any qualms with DOT brake fluid having previous experience with juice brakes on motorcycles. With the dual syringe bleed set-up, flushing the system annually will be easy and inexpensive.

If/when I convert my Crosstrail Sport to juice brakes, I will take another look at the Shimano Deore.

FrontRanger

That's a good deal on those Levels. Here are some videos you might find useful:

Trim -- Bleed --

XCSKIBUM

I've already watched a slew of videos. Since I'm opening a small scale repair shop in my garage, I also ordered a "PROFESSIONAL BLEED KIT" with the brakes. It does not include the "Bleeding Edge" hose, but that is only needed on the high end Level calipers. I'll order one of those later as business volume dictates.





An interesting note on the bleed procedures is that the "Bleeding Edge" calipers use the opposite sequence. The standard calipers are vacuum/pressure bled from the bottom.

gsa103

I suspect it doesn't really matter, or it's a minor difference in how trapped air is extracted.

One thing with bleeding, is that if you have a system with air in it (spongy lever). Remove the caliper from the mount, that way you can rotate it all over the place to release pockets of air.

Those look like good brakes, the Guide brakes have been well received so I would assume Level is similar.

XCSKIBUM

Well, I think the difference in the bleed procedure is due to the fact that the bleed port on the caliper is on the bottom for the 'Bleeding Edge" calipers, and on the top of the standard calipers. As you cited, a difference in how trapped air is extracted.

I can see the logic for not only the different bleed procedure, but also the location of the ports given the Bleeding Edge port can be opened and closed while sealed with the probe. It's a quite ingenious bit of engineering IMO. I wish I could afford or even justify spending 2-3X as much for the TLM or Ultimate versions respectively. Supposedly, they all have the same lever/master cylinder technology, from bottom to top of the line. With the basic models you give up tool-less adjustment of the levers, 2 piece, upgraded caliper construction from the TL on up and all the bells and whistles like the Bleeding Edge, etc on the TLM & Ultimate.


The Guide series has 4-piston calipers and the Level has only 2. The Level has similar lever/master cylinder technology as the Guide, it just doesn't have the braking power. The Guide is for DH while the Level is for XC/trail riding and is marketed as such. I think the Level will be all I need for my type of riding since I would not be riding down anything I couldn't ride or push the bike up. In ascending levels of difficulty, I ride mostly abandoned RR beds, XC ski trails, snowmobile trails, horse trails, etc.