dadof2 Posted June 13, 2015 Report Share Posted June 13, 2015 Just thought I would post some brief, easy to follow advice in view of the number of people who seem to have difficulties with hydraulic brakes or clutches. I would say at least 90% of these problems could be avoided by a few simple steps. 1) Change the fluid (full bleed through) every 6 months or more frequently. Use DOT 4 or HSMO as appropriate. Do not use silicone based fluids. If you see any dirt in reservoir, syringe it out, don't bleed it into other parts of system. 2) When you first get your bike remove the bleed nipples and re fit them using PTFE tape on the threads 3) Check your pads regularly to make sure they move freely and are worn evenly. Any uneven wear or sticking causes uneven force on the slave piston(s) causing tilt. 5 Quote Link to comment Share on other sites More sharing options...
baldilocks Posted June 14, 2015 Report Share Posted June 14, 2015 Have you got shares in a brake fluid company? Given issues people have bleeding systems you're recommending everybody remove the bleed nipple on a system thats working to apply ptfe tape? I haven't had to do this yet and have been using hydraulic brakes since 1991. 3 Quote Link to comment Share on other sites More sharing options...
dadof2 Posted June 14, 2015 Author Report Share Posted June 14, 2015 Have you got shares in a brake fluid company? Given issues people have bleeding systems you're recommending everybody remove the bleed nipple on a system thats working to apply ptfe tape? I haven't had to do this yet and have been using hydraulic brakes since 1991. I did intend this to be very brief but since a few points have been raised I will explain a bit more. I do not have shares in a brake fluid company, but I do get it trade / very cheap. Even if you pay full price a litre of high quality DOT 4 is less than a £tenner and will do 3 or 4 full changes on a typical trials bike. Water gets into brake systems. Silicone fluid does not absorb water, leaving it free to cause corrosion or reduced lubricity. DOT4 absorbs water preventing it doing damage. As DOT4 absorbs water it darkens, looses performance and can even form varnish that causes pistons to stick. Clean DOT 4 absorbs all this crap, reduces corrosion and keeps things moving freely. Why PTFE tape? If air can get past the threads it can make bleeding difficult as it gets drawn into the cylinder on the return stroke when bleeding. I have lost count of the number of seized / sheared / rounded off bleed nipples I have removed (by TIG welding). Putting PTFE on them when new prevents them seizing. You just get a friend to put a finger on the bleed nipple hole whilst the nipples out and hardly any fluid is lost. As rich1983 says, he has spent ages sorting hydraulics once they have gone wrong, regular fluid changes greatly reduces chances of them going wrong in first place. "If its not broken, don't fix it" maybe "a stitch in time saves nine" is more appropriate to brake servicing. Unfortunately even doing all my initial post suggested does not stop (but it does slow) corrosion behind the slave cylinder seals, which is quite a frequent cause of brake problems. 2 Quote Link to comment Share on other sites More sharing options...
baldilocks Posted June 15, 2015 Report Share Posted June 15, 2015 People will enjoy life a lot more if after spending 5k on a bike they simply ride it rather than solving imaginary problems. 2 Quote Link to comment Share on other sites More sharing options...
al_orange Posted June 15, 2015 Report Share Posted June 15, 2015 People will enjoy life a lot more if after spending 5k on a bike they simply ride it rather than solving imaginary problems. Well that's very cynical! I mean, how often do people ride? a couple times a month maybe in the UK.. if you aren't in the garage tinkering then how on earth are you supposed to get away from the wife and kids on a regular basis?? I don't know about a new bike but my 2001 beta needed PTFE on the bleed nipples and it worked a treat. Points 2 and 3 are sound. I would agree with point 1 but I like to leave brakes alone until they need it. I just keep an eye on the pads and caliper and make sure it all moves freely. Quote Link to comment Share on other sites More sharing options...
baldilocks Posted June 15, 2015 Report Share Posted June 15, 2015 2001 ? 1 Quote Link to comment Share on other sites More sharing options...
dadof2 Posted June 15, 2015 Author Report Share Posted June 15, 2015 People will enjoy life a lot more if after spending 5k on a bike they simply ride it rather than solving imaginary problems. I have heard some things in my time but this ones a first, preventative maintenance described as "solving imaginary problems" After reading some of the posts I get visions of people threatening their callipers with a crucifix before they dare touch them with a spanner. I know I have cursed them a time or two, but do hydraulics really hold that much dread? Quote Link to comment Share on other sites More sharing options...
nigel dabster Posted June 16, 2015 Report Share Posted June 16, 2015 Yes they do to the vast majority of riders, its a shame you cant see whats in front of your face. Baldilocks bikes when ive taken any notice are well prepared and looked after and whilst both of us probably dont ride as much as we would like and get new bikes not infrequently, ive never bothered with ptfe tape and would imagine its use would simply create more problems than it solves for the majority of non mechanic riders. There is alot of difference between air filter and changing oils type prep and hydraulics for many. IMHO dont touch bleed nipples unless bleeding. Quote Link to comment Share on other sites More sharing options...
breagh Posted June 16, 2015 Report Share Posted June 16, 2015 Can't say I've had much bother with brakes and I ride a lot. Always blow any muck out the calipers with an airline after washing would be my tip. Also change the pads before you start using the brake pistons for friction material helps. Quote Link to comment Share on other sites More sharing options...
timp Posted June 16, 2015 Report Share Posted June 16, 2015 I would guess that the vast majority of vehicles have never had the brake fluid changed. I had a tractor serviced by a main dealer and the mechanic drained the coolant and replaced it. Only a year old. I was devastated! Quote Link to comment Share on other sites More sharing options...
zippy Posted June 16, 2015 Report Share Posted June 16, 2015 Also change the pads before you start using the brake pistons for friction material helps. What? are you rich or something? replace the pads before using pistons to stop. what madness is this? 1 Quote Link to comment Share on other sites More sharing options...
dpyam Posted June 16, 2015 Report Share Posted June 16, 2015 I got "maximum value" out of the brake pads on my mountain bike avoiding this preventative maintenance game, and when the front brake eventually failed, the bramble bushes at the bottom of the hill provided all the retardation required..... Quote Link to comment Share on other sites More sharing options...
guys Posted June 16, 2015 Report Share Posted June 16, 2015 I did intend this to be very brief but since a few points have been raised I will explain a bit more. I do not have shares in a brake fluid company, but I do get it trade / very cheap. Even if you pay full price a litre of high quality DOT 4 is less than a £tenner and will do 3 or 4 full changes on a typical trials bike. I wouldn't advice buying 1 litre bottles, especially if it's for one bike only. Once the seal of the bottle is opened and air can get in, the brake fluid starts to absorb water and deteriorate. Quote Link to comment Share on other sites More sharing options...
b40rt Posted June 16, 2015 Report Share Posted June 16, 2015 I wouldn't advice buying 1 litre bottles, especially if it's for one bike only. Once the seal of the bottle is opened and air can get in, the brake fluid starts to absorb water and deteriorate. PTFE tape on the bottle to ...... 1 Quote Link to comment Share on other sites More sharing options...
dadof2 Posted June 18, 2015 Author Report Share Posted June 18, 2015 DOT 4 is designed to withstand exposure to typical atmospheric conditions via a pin holes sized opening for at least 2 years. The amount of moisture let in by opening the bottle a few times in 2 years is negligible, but what Guy says is best, keep it sealed as long as possible. On a vehicle where the brakes reach a high temperature a bit of atmospheric water in the fluid degrades the fluid and lowers the boiling point much more rapidly than in a low temp application like trials bikes. PS never intended this topic to be a lengthy discussion on brake maintenance, just hoped to help a few avoid common problems Quote Link to comment Share on other sites More sharing options...
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