# Disc brakes not as responsive after rain



## aballz (Sep 12, 2008)

Hi guys, 

I'm hoping there's a simple answer to this. I have an older GT avalanche 3.0 with disc brakes. Last week, i took the bike out and rode it in pretty heavy rain (for fun). I've never ridden in real rain before so i decided to give it a try just to see how it feels. The ride went well, i got drenched and my clothes weighed me down quite a lot by the end of the ride. 

Now a week later, my rear brakes don't seem to be functioning well. It doesn't seem as strong anymore. I have trouble locking out my rear tire now. The front brakes still work fine. I probably should have rinsed the bike off last week but i figure the rain was doing that for me already. I did ride along the beach area but not into the sand or in any type of dirt trail. So i assumed there may be some sand picked up from the wind that got into my brakes, i tried to rinse them with water but it had little effect. 

So, a few questions...are my brakes dead? Do i need to replace them? What should i have done to prevent this from happening?

Thanks for any input you guys may have.


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## SlimTwisted (Jun 14, 2006)

Unlike rim brakes, discs should be fairly unaffected by moisture like you encountered. Assuming these brakes are manual (and not hydraulic) disc?

If so it is more likely that your brake cable has stretched (very common). More unlikely is that your pads have simply worn down to the point where braking power is affected (and the fact that you noticed it in the rain would be coincidental).

If in total doubt, take it to your local shop for a tune but I would bet worst case scenario would be a new brake cable.


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## Psycho Mike (Apr 2, 2006)

What make and model of brakes are they, Aballz?


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## aballz (Sep 12, 2008)

I heard disc brakes tend to last awhile so i highly doubt that it's worn down to the point where stopping power is affected. The bike is a 05...not really too old and yes they are mechanical disc. Cable stretch sounds like something that could have happened. Do i need to replace the cable or can i just google up a video that'll teach me how to readjust the cable? I find it a little weird that it would be stretched so many years down the line though.

Edit: We're not talking simple brake adjustments like turning the knob next to the lever right?


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## aballz (Sep 12, 2008)

They are the Tektro IO Mechanical Disc brakes according to bikepedia.


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## Bikinfoolferlife (Feb 3, 2004)

I doubt it's cable stetch if your brakes are well settled in, but you might check for glazed pads, possibly you splashed into something with some contaminants and got something on your pads and/or rotors. Have you even pulled the pads out to have a look? It's not just that you have some pad wear and need to readjust your brakes, assume that would be the first thing you'd check, right?


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## perttime (Aug 26, 2005)

aballz said:


> so many years down the line though.


If the bike has been in use for years, it is quite possible that the pads are getting worn.


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## zarr (Feb 14, 2008)

aballz said:


> I heard disc brakes tend to last awhile so i highly doubt that it's worn down to the point where stopping power is affected. The bike is a 05...not really too old and yes they are mechanical disc. Cable stretch sounds like something that could have happened. Do i need to replace the cable or can i just google up a video that'll teach me how to readjust the cable?  I find it a little weird that it would be stretched so many years down the line though.
> 
> Edit: We're not talking simple brake adjustments like turning the knob next to the lever right?


I hear using compressionless brake cable housing helps. You can get a 25 foot roll of Alligator at pricepoint.com for $19.99. If you sign up for their mailing list they might send you a email for their free shipping special running now or maybe someone who has it can forward it to you.Look on the best deals forum there is a thread there that might help you out with that deal.


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## aballz (Sep 12, 2008)

Sad to say, i don't have any experience in the disc brake area...never had a problem with them. But if that's what i should do first, i'll pull the brakes tomorrow and give them some cleaning with some rubbing alcohol? I've been cleaning the discs with rubbing alcohol. 

Is it okay to use automobile brake cleaners on them? I have a whole bunch of that pyroil brake system spray cleaner at home.


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## Bikinfoolferlife (Feb 3, 2004)

Do you know how to adjust them? Do you have a manual for them? What brakes are they?


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## aballz (Sep 12, 2008)

They are the Tektro IO Mechanical Disc brakes. I believe i found the instructions to them here.

http://www.tektro.com/04support/pdf/IO-English.pdf


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## Jerk_Chicken (Oct 13, 2005)

I would bet the pads are done. Water rides tend to do that to 4 year old brake pads sometimes.

If you don't have the expertise, then go to a shop. They'll sort it all out for you. The next thing is to not mess around with your brakes. They can potentially save your life, so take them seriously, and not as a gimmick item.

I also shy away from automotive brake cleaner because it's residue-less in an automotive setting; there is a light residue that automotive brakes can burn off during an application or two, but it tends to linger on bike brakes. There are specific brake cleaners for bike brakes, however. If you want to use the brake cleaner, you can wash it off with alcohol afterward.


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## aballz (Sep 12, 2008)

Well the front ones still work well. If i do mess up the rear ones, i'll have my money's worth when i bring it in to the shop. Either that happens or a little cleaning of the pads may help.


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## Bikinfoolferlife (Feb 3, 2004)

Can't imagine not knowing how to deal with my brakes, like JerkChicken says, your life depends on them (as well as a few other things on your bike). Are your pads actually 4 years old and never been adjusted or did your shop take care of you? Details, man, details. That manual looks reasonably complete, though...like you said, worst case you take it to the shop for a rescue. Good luck in any case.


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## vk45de (Feb 1, 2009)

easy test:
clean rear rotor, swap front pads back and see if its the pads


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## perttime (Aug 26, 2005)

The rear of the bike, even a disc brake, tends to get more of whatever the tyres throw in the air. That leads to more wear on the rear pads.

Can you get those pads out and see how they look?


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## aballz (Sep 12, 2008)

Bikinfoolferlife said:


> Can't imagine not knowing how to deal with my brakes, like JerkChicken says, your life depends on them (as well as a few other things on your bike). Are your pads actually 4 years old and never been adjusted or did your shop take care of you? Details, man, details. That manual looks reasonably complete, though...like you said, worst case you take it to the shop for a rescue. Good luck in any case.


I'll spend some time learning about disc brakes tomorrow. I know how to remove and adjust the regular linear v brakes. But for discs...guess i'll take them out see if their worn out. I'll take a picture or something. The pads are 4 years old but the bike was rode hard for only for a year though. It sat in the garage at the during the early years.


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## Interceptor1 (Feb 10, 2009)

What I’ve done is remove the pads and drag them evenly across a sheet of fine sandpaper (like #600-#800) to clean the caked in layer of contaminants or glazing, make sure you do this on a flat surface and don’t tilt the pads. Clean the discs with alcohol to eliminate contaminants. Reassemble, and check the gaps to see if you need to adjust the clamping gap between the rotor and pads and also centering the caliper on the disc with the knob. About the cable you can try loosening the end near the caliper, keep it pulled with pliers while you retighten the hex bolt and then fine tune the tension with the barrel adjuster near the lever. See if it works for you, if not change the pads and adjust the cable to the new thickness.


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## aballz (Sep 12, 2008)

Hi guys, so i took the brakes off today and i have the pictures below. I've cleaned them with rubbing alcohol but the brakes still aren't responding well. I've retuned/tightened the cable again and still i'm not able to lock out my rear anymore.

Before
https://s681.photobucket.com/albums/vv177/aballz_2009/?action=view&current=before.jpg
After
https://s681.photobucket.com/albums/vv177/aballz_2009/?action=view&current=after.jpg

When i'm not on the bike, the rear will lock when i pull the lever. Not when i'm on it with my weight though. I didn't get a chance to sand it down with anything because i didn't have any sandpaper with me. Does the 'after' picture look clean enough to you guys?


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## emtnate (Feb 9, 2008)

Those pads look pretty smooth to me. You should really try sanding them, especially the one on the left.


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## Bikinfoolferlife (Feb 3, 2004)

Keep in mind after cleaning your rotors you need to allow another bed-in period...

Hard to tell by sight if a contaminant has permeated the pads, though. What's the thickness of the pad material left now?


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## aballz (Sep 12, 2008)

I would say the thickness is pretty good. As thick as a nickel sized coin on one side, maybe slightly more worn on the other. 

As for sanding them, i'll try to find some time to go buy some sand paper. They look pretty smooth to me as well. I didn't touch them due to the fear of more contamination.


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## zarr (Feb 14, 2008)

aballz said:


> Hi guys, so i took the brakes off today and i have the pictures below. I've cleaned them with rubbing alcohol but the brakes still aren't responding well. I've retuned/tightened the cable again and still i'm not able to lock out my rear anymore.
> 
> Before
> https://s681.photobucket.com/albums/vv177/aballz_2009/?action=view&current=before.jpg
> ...


1. Get a small lcd flashlight and/or a head mount flashlight and a pair of strong reading glasses so you can see the space between the rotor and pad real good. 2. Buy some new pads!


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## aballz (Sep 12, 2008)

I believe i found the conclusion to this issue. So i did what vk45de said to do was to swap the front and rear brakes and the problem didn't go away. The front brakes worked fine and the rear was still struggling to slow me down no matter which pads i use. Now that we've eliminated the brake pads being the issue, i'm guessing it must be the cable. I believe someone above mentioned cable stretch. I think the cable somehow lost it's integrity after riding in the pouring rain. I've already tried re-tightening the cable but that has little effect. If anyone has another idea of what may have happened, i'm open to your suggestions. Thanks everyone!


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## perttime (Aug 26, 2005)

How is the cable outer? Ends fixed where they should be fixed? Cable not sticking?


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## aballz (Sep 12, 2008)

Hm. The lever was a little stiff, but it doesn't feel that stiff anymore. Which areas would it stick at?


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## perttime (Aug 26, 2005)

I guess the most likely areas for sticking would be the ends, where the cable comes out of the outer, and any bends.

Is the mechanism moving freely at the calipers? Same front and rear?


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## aballz (Sep 12, 2008)

So i did a little lubing to the end of the cables, i'll see how it turns out tomorrow. The brakes are getting better. Although i have to squeeze pretty hard, but they are starting to lock up again. I appreciate everyone's help in troubleshooting this matter. Thanks!


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## madmagrider (Jan 30, 2008)

Make sure your cables didn't fray inside the housing. This happened to me and I couldn't figure out why the brakes worked poorly for a couple of weeks. I removed the cable from the rear brake and lever to check for binding, and sure enough, the cable was very hard to pull. I removed the cable from the housing and a few strands had snapped and bent over backwards.

If it's been years since you changed cables and housings, I'd change them whether this is the problem or not. Either way braking will likely improve.

BTW, Tektro IO disc brakes don't work well no matter how you adjust them. When I switched to Avid BB7's I couldn't believe how much more power and modulation I gained.


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## aballz (Sep 12, 2008)

So i went for a ride today. It seems like lubing the cable did the trick. I would say my brakes feel 90% of what they were after all the troubleshooting above. This will have to do for now. I did check the cables to see if they were binding to anything; they were not. I think the biggest issue was that i must've kicked up a lot of sand from all the puddles i rode through which caused some cable stiffness. After all, I was riding along the beach through the heavy rain. Sand must've gotten into the cable housings and the lube is doing the trick for now.


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## Bikinfoolferlife (Feb 3, 2004)

aballz said:


> So i went for a ride today. It seems like lubing the cable did the trick. I would say my brakes feel 90% of what they were after all the troubleshooting above. This will have to do for now. I did check the cables to see if they were binding to anything; they were not. I think the biggest issue was that i must've kicked up a lot of sand from all the puddles i rode through which caused some cable stiffness. After all, I was riding along the beach through the heavy rain. Sand must've gotten into the cable housings and the lube is doing the trick for now.


Generally you want to periodically check the cable/housing interface, i.e. is the cable moving smoothly and easily in the housing. If you run a full housing run from lever to caliper it will help keep contaminants out, too; interrupted housings offer more opportunity for friction as well as contaminants...


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