Kit for bleeding Hayes disc brakes



aussiextc

New Member
Jul 29, 2011
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I note the Hayes bleed kit doesn't have many favourable reviews. Is there a better alternative to the Hayes kit? How often should I bleed my brakes?
Thanks
 
Where are these reviews? Always bear in mind that web reviews are usually skewed to the negative (happy cosumers tend to stay quiet, whilst grumpy ones are more vocal)

When you say "bleed kit" what you're refering to is a large volume hypodermic, a short length of hose and, perhaps, a nozzle to attach it to the brake. It might also come with a small bottle of fluid but you don't have to use hayes fluid. They are really very simple kits made of rather flimsy stuff. Bike shops never buy more than one kit (for the nozzle) because, after that, breakages can be covered by buying fifty cents worth of plastic tube from the hardware or a two dollar syringe from surgical supplies.

Bleeds should only be necessary if there is an ingress of air, water or dirt into the fluid which causes a degradation of performance. If your brakes are working fine then there is no reason to bleed them. Therefore, most consumers shouldn't need to do this regularly at all. I sold my last MTB to a mate five years ago. Since new it has had no more than new pads.
 
Thanks for the reply Tafi. My main reason for asking is that I have just found I have no front brake (handle goes to the bar) and my rear brake is rubbing. LBS is charging me $33 each end to do a bleed to see if this is the problem. I was wondering whether this was needed as regular preventative maintenance as some posts mention this as well as fluid changes every 12 or 24 months. The Hayes kits I have seen only have squeeze bottles no syringe.
 
Originally Posted by aussiextc .

My main reason for asking is that I have just found I have no front brake (handle goes to the bar).. ...LBS is charging me $33 each end to do a bleed to see if this is the problem. I was wondering whether this was needed as regular preventative maintenance as some posts mention this as well as fluid changes every 12 or 24 months.
Sounds like there is either no fluid or a lot of air (or both) in the line. In any case a bleed is definitely needed (at least) to help diagnose the issue. 30 ish dollars sounds about right.

I doubt that a bleed can be considered preventative maintenance. All a bleed does is flush out the old fluid and replace with new. If the fluid leaks or is dirty or watery or aerated, this is a symptom of a sealing problem, not a fluid problem (unless poor fluid or poor technique was used in installing the brakes in the first place). However, there has been the occasional "freak" loss of pressure which has been solved with a bleed. Bleeds (as in this case) are important from a diagnostic point of view. It will allow any leaks to be found (and hopefully solved).

The solution can be a simple as tightening up the sealing bolts at the lever or caliper (which would be done during the bleed), or the replacement of the master cylinder seal. It can also not be solvable, in which case you might need to fork out for a new brake (jump that hurdle if you come to it).


Originally Posted by aussiextc .

The Hayes kits I have seen only have squeeze bottles no syringe.
The principle seems to be the same, though I'd still rather use a syringe, which is more controlable.

NB: I have yet to see a bike with one of the newer Hayes brakes. All the ones I see are either Avids, Shimanos or older Hayes (Hayes 9, Sole etc).