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Discussion Starter #1
Replaced my girlfriends clutch and brake levers with some aftermarket ones. The brake works fine then when it sits for a bit, it becomes hard to pull like air is being let in. I re installed them again with the same issue persisting, and even bled the brakes. I can't for the life of me figure out wtf is going on with the front brakes.
 

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Discussion Starter #2
Just to clarify, there's too much pressure in the brake system for me to even pull the lever an inch. The brakes worked fine before I installed the lever. I replaced the levers the same way I replaced mine on my 08 without this issue. So I'm at a loss right now
 

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Make 100% sure you have the proper lever mount/perch and that the little nipple from the master cylinder goes all the way straight into the recess on the perch. In this recess there's a ball-nut thing that can block the nipple from going in as deep as it needs to.

I had this happen on my 09. The result is that the lever essentially engages the brake partially before you even activate the lever.

Does your front wheel spin freely with no brake applied? If not then some amount of brake is being applied.
 

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Discussion Starter #4
Make 100% sure you have the proper lever mount/perch and that the little nipple from the master cylinder goes all the way straight into the recess on the perch. In this recess there's a ball-nut thing that can block the nipple from going in as deep as it needs to.

I had this happen on my 09. The result is that the lever essentially engages the brake partially before you even activate the lever.

Does your front wheel spin freely with no brake applied? If not then some amount of brake is being applied.
I haven't been able to test the front wheel freespin yet. When I bled the brakes it worked like normal and the within minutes the pressure builds up until it won't pull any more. I'm a little confused what you mean by perch/nipple. Are you referring to that rubber plunger thing that goes into the open area within the lever?
 

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I haven't been able to test the front wheel freespin yet. When I bled the brakes it worked like normal and the within minutes the pressure builds up until it won't pull any more. I'm a little confused what you mean by perch/nipple. Are you referring to that rubber plunger thing that goes into the open area within the lever?
Yea, the plunger thing is what I'm calling a nipple. If it doesn't enter the open area straight and deep it will apply brake. When it happened to me I had just done a brake fluid flush and was proud of myself how firm the lever felt. It was firm because it was like 20% engaged. My front wheel spun but not as freely as it should.

When I took the test drive afterwards my caliper locked up after a few applications.

I can't see any scenario where a system pressurizes itself by sitting.
 

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Discussion Starter #6
Yea, the plunger thing is what I'm calling a nipple. If it doesn't enter the open area straight and deep it will apply brake. When it happened to me I had just done a brake fluid flush and was proud of myself how firm the lever felt. It was firm because it was like 20% engaged. My front wheel spun but not as freely as it should.

When I took the test drive afterwards my caliper locked up after a few applications.

I can't see any scenario where a system pressurizes itself by sitting.
Yeah that's the issue. It works fine then within minutes starts to pressurize. Today I went back out to check it and it was as stiff as could be. I don't know if air is entering the system somehow and pressurizing it or what ?
 

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Discussion Starter #7
I'm gonna check to make sure there's nothing inside the lever that's stopping that nipple from going in all the way
 

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Put the stock levers back on and see if it goes back to normal operation.

My bet is it will.

Aftermarket levers are hit and miss, mostly hit but a lot of miss. @Bat-1 is probably onto the issue.
 
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Discussion Starter #9
Put the stock levers back on and see if it goes back to normal operation.

My bet is it will.

Aftermarket levers are hit and miss, mostly hit but a lot of miss. @Bat-1 is probably onto the issue.
Interesting. I'm betting that the plunger off the MC isn't seated correctly into the lever. I reinstalled it twice and it's still doing it but maybe I just wasn't aware of that issue so I wasn't making sure it was seated properly I'm gonna throw the stock one back on like you said to figure out if it's just the lever and not something wrong within the system
 

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That's almost certainly it as air entering the system would result in a softer lever (gases compress, liquids don't).

On most lever mounts the part the plunger goes in has a type of ball/nut deep in the recess that has to be lined up to make the recess deep enough or it blocks the plunger.

With Chinese lever sets the levers are mostly the same, only the mounts change. They usually have a model number stamped onto them. This bike needs the F33 mount. The very similar F35 looks the same but will cause these symptoms.
 

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Discussion Starter #11
That's almost certainly it as air entering the system would result in a softer lever (gases compress, liquids don't).

On most lever mounts the part the plunger goes in has a type of ball/nut deep in the recess that has to be lined up to make the recess deep enough or it blocks the plunger.

With Chinese lever sets the levers are mostly the same, only the mounts change. They usually have a model number stamped onto them. This bike needs the F33 mount. The very similar F35 looks the same but will cause these symptoms.
just checked and its the F33, and all that inside the brake lever is like a recess with a gold bar or something. theres no notch in the bar so it seems like the plunger pretty much stays up against this gold thing. I did notice that there was a notch on the inside of the recess off to the side like the plunger was possibly off to the side a little and was resting up against that opposed to against that gold part, i just tried reinstalling but the lever is still somewhat stiff which i assume is because the brake pads are snuggly up against the caliper to the point where i feel i should take off the calipers and press back the brake pad piston
 

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The little gold cylinder should rotate, I think. There should be a small hole in the gold cylinder for the plunger coming off the MC to seat into. I took a little flashlight and tried to get my eyes as close to line-of-sight with the plunger as possible when I reinstalled my shorty levers so that I could see the plunger going into the hole in the little gold cylinder. I'll try and take a picture tonight when I get home.
 

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Discussion Starter #14
The little gold cylinder should rotate, I think. There should be a small hole in the gold cylinder for the plunger coming off the MC to seat into. I took a little flashlight and tried to get my eyes as close to line-of-sight with the plunger as possible when I reinstalled my shorty levers so that I could see the plunger going into the hole in the little gold cylinder. I'll try and take a picture tonight when I get home.
If there's suppose to be a hole in the gold cylinder then that is definitely the problem because there wasn't at all. I figured maybe I could rotate it but I had no idea how I would even do that. if you could take a picture that would help so much, and maybe some insight into how to rotate it !
 

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Have you put the OEM levers back on to see if everything worked as it should?
 

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Discussion Starter #16
Have you put the OEM levers back on to see if everything worked as it should?
No I've been wanting to but I'm almost certain that something's wrong with the lever
 

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This was the best I could do without disassembling things over my lunch break, hopefully this explains what I described above. On the underside of the lever you can see where the gold colored cylindrical piece is installed into the lever, held in with a cir-clip. Should be easy to rotate the cylinder from either the side of the lever, or the underside. On the top view hopefully you'll be able to make out the plunger inserted into the hole in the gold cylinder. I think you have just been installing the lever with the gold cylinder rotated the wrong way.

As for rotating the cylinder, I think I just used a small flathead precision screwdriver and was able to rotate it; there was not a lot of resistance. Worst case, you pull the cir-clip on the underside, re-install cylinder in the proper orientation, and re-install the cir-clip.

Hope this helps! hopefully I'm not sending you off on a goose chase.
 

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That gold cylinder should swivel (easily). Use a pick to turn it. A toothpick will work unless yours is stuck or was machined too large.

I happen to have one of these mounts handy. Photos show cylinder with detent (this is what yours needs to look like when installing) and blocked.
 

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Discussion Starter #19
Thanks guys!! I'm gonna check this out tonight. So when you rotate it, should you rotate it from the underside where that clip is? Or try and rotate the cylinder where the plunger would go? And I either Case, I'm guessing just put some pressure on it with whatever object and try to rotate it?
 

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Discussion Starter #20
Mines definitely blocked for sure
 
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