[ros]

07,trx 400 ex, leaking brake fluid bad around rubber boot where cap screw is.
Just bought today know nothing about this machine. Quite capable of most work needed.
Do not know whats involved in rebuilding or if more trouble than it's worth. So the question is to rebuild or not to rebuild. Some input please.
Thank you in advance.

 

[Here 2 help]

Rebuild is simple if piston is not damaged - may only need an o-ring for the parking brake post. Can replace piston seal while working on it (would recommend it)

 

[ros]

Thank you,
Spoke to many people. Non real mechanics. They all had same results. Had to pull apart again. Still leaked.
Some said lot of pressure need special tools. Looks like I may just break apart.
Many thanks.

 

[Here 2 help]

No special tools needed unless it is damaged or neglected to the point that special tools are needed to correct the damage.

 

[ros]

Once again thank you
You have made my mind up for me.....

Let me put another question to you.
I do not do things half way if I am going to do it I am going to do it correct. Where is best supplier to get rebuild kit, what kit, are there different versions of kits and finally what brand rebuild kit... ?
Once again thank you.

 

[Here 2 help]

No kits - just buy the needed parts from Honda

 

[Trx450R]

Yes thats all you need just a few simple o-rings most likely, bust if piston is siezed inside you can heat it up and force it out than just run emery paper around the piston to clean it up and clean up its cylinder should be fine

 

[ros]

Great thank you for the education

 

[ros]

Finally making some headway. I rebuilt the rear caliper. Could not have been more simple, nothing to it.

 

[kartl]

I agree just buy what you need. Also inspect for future parts that may need replacement like pads and brake line. And make sure to change the brake fluid regularly.

 

[ros]

I finally put back together with all my issues hmmmm....
engines seems to run great .
My brakes ,I believe I do have an issue with.

Educate me please......
Rebuilt caliper, all went well.
Bled system, no issues there.
New, EBC heavy duty pads.
Made sure no oil, grease or fluids leaked on pad or disc.
Cleaned up disc with emery cloth then cleaned with brake cleaner had looked like burnt or glazed but looks okay now.

To the point, I have great pedal pressure But does not stop proper, not grabbing disc like front brakes do.

Educate me, do I have a bad disc?

 

[Here 2 help]

Tough call here without being able to see the components, but......

Heavy duty or severe duty brake pads do not "grab" as well as the cheaper "soft" organic pads. They last longer and are less affected by water, but they require higher pressure before locking-up.

Also, the metalic pads take longer to bed in. Take the machine out to where you can get it up to near top speed, then jam on the brakes to haul the speed down to about 1/4 of top speed - accelerate up to near top speed and jam on the brakes, repeat about 4 times then let the brakes cool down (about an hour). This process is known as "bedding-in". It helps conform the pads to the shape of the rotor and tempers the pads for longer life.

After this process you will probably have better brakes, but remember, the front brakes are for stopping and the back brake is for control. Practice using both.

 

[ros]

Disc specification

Another thing I was thinking of knowing that the prior person destroyed the caliper by not replacing rear pads using piston on disc to actually stop. My thought was / is the disc too thin, out of spec, knowing prior fact. I put a pair of veneers on disc not as good as micrometer, it shows under spec by a little , not by much though, gonna get a micrometer to do better measurement.

Thanks again Sir.....

 

[Here 2 help]

Rotor thickness will not affect stopping, but if the rotor gets too thin it becomes a safety issue. Too thin and it will fail

 

[ros]

braking

Yes everything functions properly. Just does not grab disc like I would like it to. I will try heating up the pads like you suggested. Thanks Again.