RGS rear brake travel

[andrew112_uk]

Hi everyone, Can someone please tell me what the normal rear brake pedal travel is on a RGS?

I changed the brake light switch and bled it but I have 4cm /2" of travel and I can't remember if it was always that way. When
I bleed it, pressing the pedal only produces a dribble of fluid but getting the nipple open much is difficult. There are no visible
leaks. Pumping it makes no difference.

Brake light works fine though 

Thanks!  Andrew   

 

[Simonr501]

The travel on the end of the brake lever on my Jota 120 is probably about 1" or just under. There probably is a grub screw to adjust backlash on the actuator on the RGS.

I did have a similar issue.
I strongly suspect that there is some air trapped in the system.
In my case Keith N advised that I should unbolt and raise the caliper as high as possible to allow air to get out when bleeding. It worked!

The rear caliper is at roughly the same level as the master cylinder, so bleeding is not as easy as the front.

There is also the chance that the tiny hole within the master cylinder bore may be blocked, which also makes life difficult when bleeding. This means stripping the MC and sticking a bit of wire in to clear the hole.

In the meantime, with everything still in place you might want to take the cap off the MC and have a look at the fluid when you pump the lever, if there are air bubbles rising then you may be getting somewhere.

 

[sfcpiet]

Hi everyone, Can someone please tell me what the normal rear brake pedal travel is on a RGS?

I changed the brake light switch and bled it but I have 4cm /2" of travel and I can't remember if it was always that way. When
I bleed it, pressing the pedal only produces a dribble of fluid but getting the nipple open much is difficult. There are no visible
leaks. Pumping it makes no difference.

Brake light works fine though 

Thanks!  Andrew 

Simon is most likely to be correct, there is still air in the system.  The entire brake system will need to be removed from the bike to bleed it.  There are too many kinks and loops to trap air while the system is installed on the bike, and not enough movement in the liquid to push it out.

Lever travel should be about 10-15mm before you feel definite pressure building up.

piet

 

[Terry Dymond]

Yes Andrew, the easiest way to bleed the system is to take it off and hang it up so all the air rises to the mc, not a real difficult task. HTH.
Terry

 

[andrew112_uk]

Thank you all. I had not thought about the run of the brake line preventing bleeding.

I'll take it off and do it on the bench.

Thanks again, Andrew 

 

[andrew112_uk]

Worked a treat, thanks! Just a little air in it and now it's really sharp with hardly any travel.

In case anyone looks this up in future, you don't need to take the master cylinder off, just the calliper and raise it as much as you can so that the brake line rises from the cylinder up to the calliper. I took a pic of how I did it.

 

[Terry Dymond]

Many ways to skin a cat but the principle is the same. Glad it turned out well Andrew.
Terry

 

[sfcpiet]

I do it the other way round, ie, leave the caliper nipples closed and hold the M/C up high, assuring air can rise unhindered.  Gently depressing the M/C piston about 1mm allows the air to escape to the reservoir.  No further tools required and you don't lose a single drop of fluid!

piet