Topic: Aloha again

[CB400Finhawaii]

Aloha again

This is the first forum I have joined so I am trying to figure out how everything works.

I am rebuilding my master cylinder on my 1975 CB400F.  I don't think the bike has run is almost 20 years.  I have disassembled and cleaned the master cylinder and I am working on putting it back together.  In the bottom of the reservoir, there are two holes. One goes through to the channel where are parts are while the other one does not.  The hole that does not go through looks like there is a little flap inside the hole.  Or maybe it is just a piece of junk stuck in the hole. I have tried using a small pick to see if I can get it out, but have not been successful.

Should that second hole be clear and it is a piece of junk stuck in it, or should whatever is in the hole be there?  What is the purpose of the second hole?

I tried to upload a picture, but I don't see it when I preview the post. 


Thx,
Mike

[newday777]

Yes clear that hole.
It is the return port to release the caliper piston.

[newday777]

You know you will have to bench bleed that master cylinder now at the banjo bolt before you bleed the system.

[CB400Finhawaii]

Thanks for the info.

Should both holes go all the way through to the channel?   I could not get whatever was stuck out with a pick, no matter what I tried.  So I took a drill bit and now it is clear and the hole goes through to the channel.   Let me know if I have ruined it, so I can buy a new one.

I didn't know about bench bleeding, but now I do.  Any other tips are greatly appreciated.

Mahalo.

Mike

[HondaMan]

Each of those holes feeds a different section of the piston. One feeds in front of the forward (rubber) piston and the other feeds in behind it where the second seal lives. They will both bubble while you bleed the cylinder after the rebuild.

[CB400Finhawaii]

My master cylinder rebuild is complete and I was putting the brake lever back on.  One video on YouTube put a bushing into a hole by the lever.   I looked at many different vendors and was not able to find this bushing for sale.  Is this something I need or will the brakes work fine without it?

[Don R]

 I don't think all of our M/C's have the bushing. If the bolt fits snugly in the lever hole you are good to go.

[CycleRanger]

Thanks for the info.

Should both holes go all the way through to the channel?   I could not get whatever was stuck out with a pick, no matter what I tried.  So I took a drill bit and now it is clear and the hole goes through to the channel.   Let me know if I have ruined it, so I can buy a new one.

I didn't know about bench bleeding, but now I do.  Any other tips are greatly appreciated.

Mahalo.

Mike

Check out this Honda SB regarding bleeding the MC.

[CB400Finhawaii]

Has anyone used beads that go inside an inner tube to balance a tire?  Common Motor Collective sells them, as well as on Amazon.  If so, would you recommend them. or not?

[newday777]

Has anyone used beads that go inside an inner tube to balance a tire?  Common Motor Collective sells them, as well as on Amazon.  If so, would you recommend them. or not?

Balance beads are not to be put inside tubes. Only to be used in tubeless tires and rims.

BTW I know you are still new to the forum and still figuring out how to do the forum thing, you should be asking your individual technical questions in the SOHC bikes section,
http://forums.sohc4.net/index.php/board,2.0.html not starting new threads with new questions here in New members section, that way you should get more responses there.

You can also start a Project Shop thread on your bike, if you want to keep all your questions in one thread,
http://forums.sohc4.net/index.php/board,103.0.html
start by describing your bike, how long you've had it and what you've done, then keep the progress updated as you go along and include questions there in replies in that one thread.

[tool14]

welcome aboard

[CB400Finhawaii]

Thanks for the answer.  I also wasn't sure where to post my question and now I know.

Mahalo

[rocket johnny]

welcome from western colorado ,,  good to see your making progress on your bike .   what island are you on ?   my brother is on
the big island in kona .  i try to get over at least once a year .  love it over there .

[CB400Finhawaii]

I am on Oahu in the city Kailua.  It is on the windward side of the island.  It is about 15 miles from Honolulu but world away.  Riding here will be awesome, once my bike is done.  I met two guys here that also have 1975 CB400Fs and another that has several vintage Japanese bikes. 

It is probably too cold to ride in Colorado now, but the "winter" here is spectacular.  The low temperatures are around 70.

[rocket johnny]

it is winter here on the western slope of colo.  but we get some nice days ,,  last sat. was 65 so gloves and a leather jacket and i was out the door .  i live about 7 miles away from the colo. national monument  (  google it )   22 miles of twisties  and red rocks   then to fruita  for a beer & a strombolie .   30 today with snow but life is still good         hope your making progress on your project