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Formula Oro - Oil leak at lever (more advice needed 8/11!)

 
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timmys
I seem to have an oil leak at the rubber gaiter on the rear brake lever on my relatively new Zesty, it also makes a "squishy" noise when the lever is pulled. Braking performance has been adequate so I'd pretty much ignored it, but I've convinced myself now that the brake really isn't working as well as it should do.

Here are a couple of pics of the leak (lever removed).





In comparison, the other lever is completely dry in that area.

The only thing I have checked so far is that the torx screw securing the rubber gaiter is tight - which it is. Should I try disassembling, clean, reassemble and bleed? Or should I just go ahead and order the (pretty cheap) replacement parts? Referencing the diagram below the parts come as the "Piston Kit" consisting of parts 5, 6, 7, 8 & 9 and the "Stop Piston Kit" consisting of 15, 16, 19 & 26. Does anyone one have an inclination which of the O-rings, 9 or 16 - or none of the above, is likely to be the culprit for the leak? This obviously effects which kit I need. Thanks!



'09 Lapierre Zesty 514
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nicklouseLives Here
do you have the bleed kit?

if yes open it up and clean and inspect.

if no then get the new bits and the bleed kit.

"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools Question SheldonBrown
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timmys
nicklouse wrote:
do you have the bleed kit?

if yes open it up and clean and inspect.

if no then get the new bits and the bleed kit.


Nah I don't have anything and in fact since writing the above decided to go ahead and order the parts and kit anyway as it all came to around £30.

Thanks for the advice.

I don't suppose anyone knows what size torx the screw holding the gator on is? The bleed screw is definitely a T10 but I'm not sure about the other one. It seemed to be extremely tightly done up and I'm worried I might strip it - if I knew I was definitely going in with the right tool it might help!

'09 Lapierre Zesty 514
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nicklouseLives Here
sorry cant remember an my tools aint here to check on mine.

whach out for the spring pushing the plate up when you undo it.

"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools Question SheldonBrown
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timmys
Update!

After a month of waiting for the "Stop Piston Kit" to come into stock (even though the website said it was available for dipatch "tomorrow" all through that month Rolling Eyes ), I was ready to get on with changing the parts for new. But... I've taken out the piston and one of the rubber flanges(?) looks completely different between the one I've taken out and the new one.

Here are the two side by side, the new one is on the right;



You can see that the rubber bit at the top is symmetrical on the old one (left) whereas the one on the new one (right) dips down on one side. There's no indication from the diagram in the first post in this thread that it should be asymmetrical so i'd be tempted to put it down as being mis-formed but if you check out this link it's clearly the same here so mine is certainly not unique!

http://www.chainreactioncycles.com/Models.aspx?ModelID=22475

I'm standing here with torx and bleed kit in hand so any swift advice would be appreciated!

'09 Lapierre Zesty 514
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nicklouseLives Here
looks just like mine from the K24.

i would give the distributors a call as they may be an issue. but it might also be fine.

"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools Question SheldonBrown
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timmys
nicklouse wrote:
looks just like mine from the K24.

i would give the distributors a call as they may be an issue. but it might also be fine.


Ok so if I was to fit it then how do you know which way round it goes? With it being asymmetric surely that means there is a right way and a wrong way round to fit the piston? The asymmetric part can't rotate on the body of the piston but the two slots in the long white piece (bottom of my pic above) look as though they slide into the gator (part 19) on two 'rails' but that give still gives two ways round for it to be.

Hope I'm making sense and thanks for all your help!

'09 Lapierre Zesty 514
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nicklouseLives Here
they can only go one way on the 24's which is why I am saying talk to propedal, or who imports them.

"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools Question SheldonBrown
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timmys
nicklouse wrote:
they can only go one way on the 24's which is why I am saying talk to propedal, or who imports them.


OK will do.

I've gone back and had a look at the pdf with the exploded views and the piece in question does look different between the K18's and the K24's but the part number for the replacement pistons is the same for both so I think the K24 version is probably usable in the K18. Googling around I think that different part is probably shaped that way as part of the FCS system. In order to add FCS to K18's you need to order a new piston as well as the adjustment lever and expect that rubber bit is why.

'09 Lapierre Zesty 514
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nicklouseLives Here
the K24 adjuster and bits can be retro fitted to the K18 but i dont think you can use one bit from one with the other.

As the shaped seal is part of the adjustment system.

"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools Question SheldonBrown
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