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Old 07-16-14, 02:02 PM   #1
magicmervev
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Brakes no stopping the bike

Hi guys, this is my first post on here so be gentle. I've been biking for a while, but only starting to take it to the next level. I'm starting to use my bike every day for committing to work (it's a 5min journey) and 10 - 30 mile rides through the woods etc.

I've had my Whyte 801 for about a year and I'm very pleased with it. I've just given it a good clean up after sitting in the shed for 4 months and she is looking good again. The only problem I've got is my hydraulic brakes are not stopping me at all. They squeak and no matter how hard I pull them, they just don't stop quick enough. I'd say at a rough guys they are working at about 15 - 20% efficiency. I've cleaned them and made sure there is no dirt or oil on them, I've played with the pads in the past, but have found this to be a mine field of problems if it doesn't go right.

I've always struggled with brakes. I'm 6ft and roughly 19st so I'm a big lad. Could it be that my bike just can't take my size or is there a way I can ensure my brakes stop me the way they should?

Any help would be appreciated. Thanks
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Old 07-16-14, 03:45 PM   #2
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19 stone or 260#s is fairly heavy, and may account for lousier braking than average. But not to the extent described. You also say that you've enjoyed this bike for a while, so I gather that the problem is relatively new.

I suspect that it might be related to the cleaning you did, which may have left a film on the discs or pads. Or it could be a hydraulic issue line air in the lines. I'd start with a serious degreasing of the discs and shoes using a zero-residue solvent like naphtha. If that doesn't turn the trick, I'd consult a pro who might see something that filtered by transmission via the internet.

For future reference, if/when the opportunity ari8ses, consider brakes with larger diameter discs. These provide greater braking and heat dissipation capability than smaller discs (all other things being equal).
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Old 07-17-14, 05:17 AM   #3
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I suspect that you need to bleed the brakes...especially if the brakes worked well previously. Hydraulic brakes shouldn't need too much in the way of maintenance but sitting for a few months may have caused the seals to degrade. Take it back to the bike shop you bought it from. A bleed job is about $30 here in the US and is worth the cost. You can do it but it's a messy job and the bleed kit will cost just about the same as the cost of having some one do it.
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Old 07-17-14, 07:31 AM   #4
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Thanks for the advice guys. I should have said that previously they were better than average, which for my size I was very happy with, but since I've left it / cleaned it they have become worse. I think the bleeding route could the next move. If not then I will look into bigger discs. Thanks again
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Old 07-17-14, 07:39 AM   #5
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Quote:
Originally Posted by magicmervev View Post
Thanks for the advice guys. I should have said that previously they were better than average, which for my size I was very happy with, but since I've left it / cleaned it they have become worse. I think the bleeding route could the next move. If not then I will look into bigger discs. Thanks again
Since they were fine before there's no need to consider an upgrade. The issue is related to what changed, either the time in storage, or some contamination or film from your cleaning.

Either proper cleaning, bleeding, or possibly replacing or refacing the pucks that you might somehow have degraded with a cleaning agent.

BTW - brakes that need bleeding usually have a spongy feel because of the compressibility if the air in the lines, or contamination of the hydraulic fluid. If the brakes have a solid feel and you cannot depress the lever to the bar, then it's not a hydraulics problem, and you're back to the task of getting the disc and pucks properly cleaned and restored to full friction.
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Old 07-17-14, 09:13 AM   #6
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what needs to be remembered is that you can use a solvent to clean the disc but it won't work with the pads. bake the pads in an oven for 30 min at 200 celsius and that should burn off the oil.

In general the problem sounds to me like oil on the brake surface and as mentioned before just cleaning won't work.

bleeding could be a good idea as well but it won't solve the problem.

is the brake still "hard" or has it squished or become softer?
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Old 07-17-14, 12:45 PM   #7
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only real cure for oil on Disc brake pads is buy new ones .. & dont get any oil on the next ones.
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Old 07-17-14, 12:55 PM   #8
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Well it turns out that the pads were dirty so I cleaned them, roughed them up a bit and now they work a treat. Think I will look at getting bigger discs on my next bike though. Cheers to everyone for the help. I'm very grateful. Top blokes ����
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