Switched to r6 brakes, but problems..

[FzrAtx]

Hey everyone,
The other day I received my 03-04 R6 06-07 R6s calipers and master cylinder. I installed them without problems and bled all of the air out until new fluid came out the caliper bleed screws. My problem is the brakes seem very stiff, spongy and unresponsive. I zip tied the lever to the handlebars overnight and re-bled this morning, but they still seem very still compared to the stock brakes. Anyone have similar problems or have any ideas? Any help is greatly appreciated.

Aidan

[Huckleberry]

sounds like you didnt bleed the master cylinder if you have radial master cyl you will have to bleed it first then do your calipers

[FzrAtx]

I stupidly bought the master cylinder w/o the bleed screw. Is there any other way to bleed the MC?

[Huckleberry]

can u post a pic of what u are working with as far as a m/c goes

[FzrAtx]

Yeah here is the master and a pic of the calipers I've got

[ragedigital]

Very similar to the one I had. You have to take the MC off the handlbar and make sure the air is going up through to the reservoir. I pointed my every which way till the bubbles stopped showing up.

There is air right where the bolt goes in to the MC.

darrin

[FzrAtx]

Many thanks I will go try that

[sweekster]

Ok I'll throw this out there since it's a tool anyone who works on bikes needs to have. The MityVac. I went from a completely dry brake system to fully bled and pressurized in a very lazy 15 minutes using this it. Keeps the mess to a minimum as well.

Click Here

[FzrAtx]

Alright, so I took the MC off the handlebar and turned it in all sorts off directions while tapping on the fittings to try and get any more air out. But My problem isn't lack of pressure it seems like there is plenty. The brakes are hard to pull in and aren't smooth. They should at least feel better than my old brakes right? Does anyone know if r6 brakes are a normally stiffer than fzr brakes?

[sweekster]

It should take less effort to operate them with the newer masters..

[FzrAtx]

Would air in the master or somewhere in the system make them harder to pull?

[yamaha_george]

Alright, so I took the MC off the handlebar and turned it in all sorts off directions while tapping on the fittings to try and get any more air out. But My problem isn't lack of pressure it seems like there is plenty. The brakes are hard to pull in and aren't smooth. They should at least feel better than my old brakes right? Does anyone know if r6 brakes are a normally stiffer than fzr brakes?

Hi,
I have that self same set up BUT I used s/steel brake lines not the old rubber lines which will give that spongy feel as the rubber swells as the pressure mounts.

see:-

http://www.saltmine.org.uk/fzr/

The other thing as you found the extra couple of bucks for a double banjo bolt with nipple is worth every red cent, Mighty vacs work but I found the material they were made of rotted quickly in the tropical heat & sun light but these were in extreme conditions VERY near the equator.

[thatkid]

Did you make sure everything was smooth before mounting? Any history on the parts? Seals could be tweeked or something binding inside. If they had been sitting for awhile with fluid in them, it could have corroded.

[ragedigital]

+1 on stainless lines. I don't ride a bike without them. OEM hoses are good for 3k miles per the manual.

Good call George on the banjo with the bleeder: http://www.sportbikesolutions.com/produ ... _steel.htm

Not 100% on the banjo bolt size for the Yamaha MC.

[FzrAtx]

I know i need to get some steel lines but the old brakes had rubber hoses and they felt better than the r6 ones. Anyways I just bled the whole system again. The calipers and the master at the banjo bolt, but they still feel very hard to pull in and are spongy. I bought them off ebay and they came with fluid in them but I flushed them out until new brake fluid came out, and no particles or junk came out. Is it possible I need to rebuild the calipers? If so how do you get the pistons out? These calipers don't bolt apart like the Fzr ones.