Trackbike initial brake feel

gilson · Post by **gilson** » Tue Sep 13, 2011 4:08 pm

Hi guys,

Rockingham last weekend was great but I have a question.

My firestorm Stage 1 tune track bike has an upgraded front brake MC and running the SP/CBR calipers, pro-light wavy discs and some carbon pads.

The braking performance both in power and feel is very good but when I initially press the brake lever at the beginning of each session it is spongey and moves towards the bar quite a lot. After the first squeeze it is fine and from there on feels great.

Is this a symptom of air in there? I've some quality fluid in there and and bled it well, including the MC valve.

Any thoughts? Thanks

Miztaziggy · Post by **Miztaziggy** » Tue Sep 13, 2011 4:45 pm

Mine does this too, and been bled like 5 times, im 99% sure it isnt air in there. I think that it must be some sort of movement of the pads away from the disks when it has been stood for a week or two

benny hedges · Post by **benny hedges** » Tue Sep 13, 2011 6:55 pm

try bleeding again after hard braking when there is heat in the fluid.... works for me.

gilson · Post by **gilson** » Tue Sep 13, 2011 7:44 pm

Thanks guys. Bleeding is a bleeding pain.

nora2004 · Post by **nora2004** » Sat Sep 17, 2011 1:09 pm

What M/C are you running?

gilson · Post by **gilson** » Sat Sep 17, 2011 7:18 pm

An accassotto radial one. The italian brembo;)

Stormin Ben · Post by **Stormin Ben** » Sun Sep 18, 2011 10:32 pm

Thats an interesting observation there mate

I experienced exactly the same symptoms on track with mine a few years back
They worked perfectly on track, finished the session and parked up
Come next session the first squeeze (in the paddock usually) was nearly back to the bars
But the first corner on track saw them restored to normal position

It turned out to be a characteristic of the brake pads (Carbone Lorraine SBK3s -best track only pads I've used but lethal on the road!)
I would be wary of bleeding to restore full pressure in the paddock as it may cause the brakes to bind when they get hot (that way leads to warped disk PDQ)

What pads are you using?

gilson · Post by **gilson** » Mon Sep 19, 2011 11:38 pm

Hi Ben,

I think you've hit the nail on the head. I'm using the very same pads as you stated. They were half price on eBay so snapped them up.

Well bugger me, twice.

Cheers Ben. My mind is at ease.

I wonder why this happens. Is the carbon so sensitive to the heat, retracts and then needs a bigger push towards the disc?

Stormin Ben · Post by **Stormin Ben** » Wed Sep 21, 2011 6:35 pm

Spooky!!
II guess it must be something in the construction and the way it deals with heat
I never noticed it on the road but that said they were easily the worst road pads I've ever used as they just never got hot enough!

I would be inclined to put it down to a quirk and do absolutely nothing

gilson · Post by **gilson** » Thu Sep 22, 2011 12:32 pm

Thanks Ben. I will leave them as is since they are good once warmed up.

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