Kelgate Brakes

Allan Litten · Joined: 29 Nov 2006 Posts: 53

Hi Wally,
I just read your last post - we must have been writing at the same time.
The first thing that springs to mind is fluid contamination - water in the fluid.
I don't mean droplets of water that you can see with the eye but most brake fluids absorb moisture from the air and this moisture boils at a different temperature to the brake fluid, hence the additional pedal travel to compress the water vapour when hot.

Regards
Allan Litten

Sam Zavaglia · Posted: Thu Sep 16, 2010 8:43 pm Post subject:

Hi Wally,
If the rear caliper/fluid is over heating then the pedal will go to the floor regardless of the front brake temp.
When Johnny mentioned V-Dot caliper on the back it made me think.....I'm sure V-Dot also made an alloy disc (not steel). Is this the case? If so you will need the brake pads to suit the alloy disc.

My guess is the rear is overheating, so focus on the rear setup caliper/disc/pads combo to stop your pedal going to the floor.

Whenever I've had brake fade during a race, 90% of the time it is the rear causing it and can be overcome by different brand/compound of brake pad.
_________________
www.samzavaglia.com

shaun everard · Joined: 28 Feb 2009 Posts: 111

Just a thought are the pads Defo returning and not sticking and in turn making the fluid boil up my kelgate calipers are slightly worn were the pads sit due to years of the pads rattling.

wally wallen · Posted: Fri Sep 17, 2010 8:14 am Post subject:

My thanks to everyone. I've got some things to try now and maybe something will solve this problem.
This is strange for me. People are usually asking me how to solve a problem or asking advice, not the other way around. But so far the solution to this problem has avoided me and I'm not too proud to ask for help. Wink

Thanks again,
Wally

Todd Kovi · Posted: Fri Sep 17, 2010 10:46 am Post subject:

I read through the thread and a couple of things came to mind:

Obviously you are boiling the fluid which can cause the pedal to go soft because you are now trying to compress gas build in lines instead of having a pure hydraulic state (all liquid). If you can check the fluid temp by some means as soon as the pedal starts to go soft then that would confirm the boiling issue.

Also have you compared your pad compound to what others are running and the rotor design? Some pads can start to off gas at a high rate and if you are not using slotted rotors they will fade very quickly....and even may fade with slotted rotors. Coupled with overheating the fluid it could be a contributing factor.

Lastly (having spent a few years working for Bendix braking systems as a mechanical engineer) and some what of a long shot might be that as the fluid is heating, and maybe not boiling, your system components in the master cylinder are expanding at varying rates if they are different materials (aluminum, steel). You may be getting some blow buy or leak down in this area depending on the system design. I'm not familiar with these brakes....thus the long shot comment.

It will be interesting to find out what you determine as the root cause for the issue.

Curt Smock · Posted: Wed Aug 15, 2012 6:48 pm Post subject:

Wally did you ever solve this mystery?

Brian Wilhelm · Posted: Wed Aug 15, 2012 7:44 pm Post subject: :-(

Unfortunately, we lost Wally to cancer a year ago this past May. He had narrowed it down to the pad compound. It just took too much pressure to get them to bite, which generated a huge amount of heat.
_________________
Brian

Curt Smock · Posted: Sun Aug 26, 2012 5:37 am Post subject:

I'm sorry Brian.

I actually was aware of that a year ago but having never met him, I completely forgot.

Thanks for the answer though. I had a reason for asking about the heat build up because I'm trying a couple things and you've given something critical to watch for....