Ztl2 problems

[quadracer711]

2009 xb12r bolt
I posted a couple months ago about brake problems. I finally got around to takeing the brakes off.
with the tire off and the brake pads still place I can squeeze the front brake lever and sometimes only a couple of the pistons will move. I can take and hold the ones moving down and it makes the ones not moving move when I squeeze the lever. So is this ok? I still can't figure out the pattern on the rotor tho. I was thinking it was the pads causing it. Any help would be nice guys!!!!!

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[PaulPud]

Sounds like you need to bleed the caliper better. If theres some air in there some pistons may move and some wont. The wear is really bad also, how many miles on the rotor? maybe pads were metal to metal at one point and new pads were installed on top of messed up rotor. Both my bikes have ztl2, 1 has 12k miles and other is only 4800 but both look much better then that.

 

[quadracer711]

I bought the bike brand new. There is 10k on the speedo I think I have put maybe 3k on these pads. When I changed then Oem pads they still had little bit left in but I went ahead and changed them. Never been metal to metal. The rotor is original rotor. There's no grooves in the rotor I can run my hand finger across it and its smooth. Not saying it couldn't be warped but there's no grooves. I have had a werid noise coming from the front brake when I use them. Almost like the noise crickets make except for its constant when I'm using front brakes

 

[EricZ]

Many of the multi-piston calipers suffer from pistons sticking. They get stuck to the seal's edge. You can fix it by pumping the brake lever with the caliper removed from the rotor but the pads still in. Be sure to watch the piston movement as you slowly pump the lever. If some are pushing out faster than others, you can use a screwdriver to prevent those from coming out further. The stuck pistons will free up as you pump them out. When all of the pistons have freed up, you can use the screwdriver to slowly force the pistons back into the caliper. Verify they are all free by performing the test again. You can do this procedure multiple times to help free stubborn pistons loose.

 

[quadracer711]

So I cleaned pistons and I'm gonna do a fluid flush. I'm also gonna see I can clean the rotor up some. Think I should buy some new pads or not?

 

[EricZ]

The pads look fine. Reassemble and see if things have improved!

 

[quadracer711]

Just curious what are your thoughts on the
Solid mounting kit from ebr?

 

[EricZ]

I have it on my bike and it has worked well. It is supposed to transfer more rotor heat to the wheel. Other than the increased heat transfer there isn't any benefit for their kit over the "factory" kit. It is extremely important to ensure all of the rotor hardware is in good shape, especially the square bushings that the rotor sits in. They will wear and can cause brake pulsing and noises.

 

[snrusnak]

You could also rebuild the caliper it's pretty easy and cheap. Also check to see if the rotor is in spec with a caliper and you can sand it with an orbital sander to refinish it, I've done this on my front and rear and it worked great. On the rear though I think I went too fine as I didn't have good rear stopping power for about 50-100 miles until it was really broke in. When I did the front though it worked great immediately. Unfortunately I don't recall what grit I used...

 

[quadracer711]

Well I took caliper apart cleaned the pistons and seals everything. Put it all together bled it seem to he working fine now from me watching it. Cant ride broke my belt so gotta order another one. Whats the spec on the front ccaliper? Im gonna refinish it with a orbital sander. Im also gonna order the solid mounting kit from ebc.

 

[snrusnak]

I don't recall off hand, it's in the service manual though (can download at the top of the site for free).

I believe when I did my front rotor I used something like 200-400 grit, and it worked good. I think I used something more like 600-800 grit on my rear rotor and it didn't have any bite for the first 50-100 miles. I was out on an all day ride with basically no rear brake but was still using it out of habit. Half way through the day it just started biting more and more. By the end of the day I had full braking force. Do some googling, I'm sure you can find an answer on what grit to use.

Be sure to move around a lot, don't stay sanding in one place too long.

 

[quadracer711]

Im gona try 200 today tried 400 lastnight and didnt really work the best.
Im just waiting for the solid mounting kit and belt to come in. Ill be rideing again!

 

[snrusnak]

what exactly do you mean it didn't work the best? Should just be hitting it quick, trying to "refinish" the surface. Don't try to really sand away a lot of material. I should have mentioned but did you degrease it first? (otherwise it'll clog the paper).

 

[quadracer711]

Id hit for a sec and it would pretty much just turned black I may not try again. The rotor is well within spec

 

[quadracer711]

I didnt put any pressure on it just for a split second. I honestly rdidnt think to degrease. Probaly should of thought about bout that

 

[snrusnak]

Yeah clean it first, that's why it's turning black. I'd retry with 400 grit, makes sure it's clean first though. If the rotor is in spec then it's a good idea to hit it to refinish the surface. The get lines like yours, and sometimes hazed, over time. It's good to clean them up.

 

[quadracer711]

New belt and mounting kit will be in monday.
Will report back

 

[quadracer711]

Ok just got everything back together. Part got delayed
Stops better but still getting that noise from the front brakes when useing them. Wondring if its a warped rotor?

 

[quadracer711]

also the pattern on the rotor is comeing back

 

[EricZ]

Are the pad anti-vibration springs still in the caliper?