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Discussion Starter · #1 ·
EDIT: I've decided to encompass the entire build in this thread. These are some photos of the bike before it was taken apart.

This is how it looked like before.


I never actually had it in one piece, I bought it in about 6 different boxes, completly broken down.
Here is a roller right as I started up on this project again.


When I got this bike it had been taken apart into a million different pieces. I've been starting on the frame and the engine for now but this bike will be getting a full go through.

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I finally started on my '72 CB350 that has been sitting in my garage for almost a year. Only thing I've done so for is strip the frame down to bare metal, and I built up a engine stand. Tonight I drained the oil to see how bad it was and... the drain plug was almost a 1/4 full of metal shavings! Awesome right! So my plans of a easy build are kind of out the window. I guess I'll be learning how to rebuild an engine. I have zero internal motor knowledge, so I will be asking plenty of questions on this forum as well as a couple others.

My first question is what kind of stuff do I need to look for?
What parts will I need (most likely) need to replace?

This bike will be a daily rider, and I usually stay in the fun zone of the throttle, but I'm no racer. Any and all tips are appreciated.

-Jason
 

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Re: What do I need for a rebuild on my 350?

You need to find someone close, that has some knowledge of engine internals to give you a helping hand more than likely. A tear down will tell you what parts you'll need. You can rest assured that you will at least need a gasket set, and a damn good gasket scraper and spray gasket remover-softener may help too....?

GB :mrgreen:
 

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Re: What do I need for a rebuild on my 350?

Since you found metal shavings, you'll need to tear it all apart.
No telling what you're in store for.
You can probably count on rings as a minimum, maybe valve work, maybe cam/cam bearings too.
Just start breaking it down, you'll find out.
Only parts to order right now is a gasket kit, you'll need that for sure.
You'll need an alternator tool and an oil filter bolt tool, both avaiable at Motion Pro for about $10 each.

http://www.motionpro.com/motorcycle/tools/view/oil_filter___clutch_hub_spanner_for_honda/

http://www.motionpro.com/motorcycle/partno/08-0027

You'll also need the Manual - here are two versions of the official Honda manual - each contain errors and omissions, so neither is adequate by itself......

http://home.comcast.net/~tbpmusic3/CB_CL_SL_250_350.pdf

http://home.comcast.net/~tbpmusic3/CB_CL250_350RepairManual.pdf
 

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Re: What do I need for a rebuild on my 350?

Bird76Mojo said:
.... and spray gasket remover-softener may help too....?

GB :mrgreen:

????? You have a source/link on this stuff??
 

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Discussion Starter · #6 ·
Re: What do I need for a rebuild on my 350?

Thanks for the help guys. I'll be getting out to the garage a little later.

What are your opinions on doing this myself? I'm handy, and mechanically incline, I just haven't ever been inside a motor. I got my 78 cb550 running good from a bike that wouldn't start. That was mostly carb work, and electrical.

Also is there any tools I might need beside the two mentioned above? I have a fairly good set of tools just any specifics i'll need or weird stuff?

Thanks again.
 

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Re: What do I need for a rebuild on my 350?

Jason TEAM SHRALP said:
Thanks for the help guys. I'll be getting out to the garage a little later.

What are your opinions on doing this myself? I'm handy, and mechanically incline, I just haven't ever been inside a motor. I got my 78 cb550 running good from a bike that wouldn't start. That was mostly carb work, and electrical.

Also is there any tools I might need beside the two mentioned above? I have a fairly good set of tools just any specifics i'll need or weird stuff?

Thanks again.

No, if you have a good set of general tools, all you will need ar the two special tools mentioned above.

You should be able to handle it, if you can take apart 550 Four carbs and put them back together.
If you get stuck, there's more than likely a member of this group somewhere near to you who could bail you out.
What is your location, exactly??
 

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Re: What do I need for a rebuild on my 350?

We have people here from that area, I'm sure.
If you need physical help, just put out a distress call here, I'm sure one of them will come to your aid.
If you just need advice or pointers, lots of us here will help.

Broken screws really suck......
 

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Discussion Starter · #12 ·
Re: What do I need for a rebuild on my 350?

tbpmusic said:
ol55 said:
Special tool -Digital Camera?
Absolutely !!!!!
HAHA, Will do. It's been dark out the last few days by the time I get to the bike. I'll get some tomorrow.

Thanks again for the words of advice, and confidence.
 

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Discussion Starter · #13 ·
Re: What do I need for a rebuild on my 350?

This ones going to be a long one. Okay so I got all the broken/stripped bolts and screws out. That wasn't as bad as I thought it was going to be. After I had access to everything, I worked my way around the motor taking off anything and everything. I didn't really have a method, just whatever would come off I'd take off.

First off here is some of the rubber and metal bits I was talking about in the oil. I found a lot.


I then took off all the side covers as well as the upper cam cover???



next was the starter, and the cam chain tensioner.

I think I fiqured out where rubber bits were coming from, now where is the aluminum coming from...?


to be continued...
 

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Discussion Starter · #14 ·
Re: What do I need for a rebuild on my 350?

... Okay when I got into the right side there is something sticking out of the side next to the clutch. What is it? and anyone know why there is aluminum powder all over it?


also in the same area, I got the clutch out but how do I get the rest out?


since I was stuck I moved back to the top. I finally got the upper cam shaft out, and started taking down the top of the engine.



Finally the pistons


here is where it gets kinda scary... This is the left side piston, and it's got a good amount of build up.


Here is the right piston however, with far less build up, and not the scary part. the right piston has a lot of play in it about a half inch. Is that normal? the left piston is secure and doesn't have any play.


Lastly here is the biggest piece of aluminum I found laying around inside the engine. right near the oil pump.
 

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Re: What do I need for a rebuild on my 350?

That thing in front of the clutch is the centrifugal oil filter....You'll need snap ring pliers, a bolt, and the "special"spanner to remove it........ They are almost always full of powdered aluminum "paste"..... That's what they are designed to do...remove the bits from the oil.... GET A MANUAL NOW!......
"chunked" rubber gear goes on camchain..... Loose camchain hits sides of its passage, and VOILA!.....Aluminum particles......that end up in crankcase and filter......
Everything looks about normal so far, but worry is with con-rod play......This engine should be taken completely apart and checked..... Get that spanner.....Steve
 

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Re: What do I need for a rebuild on my 350?

You didn't show pics of your cam chain tensioner and guide - I'll bet thhat's where the chuncks of metal and rubber came from.
 

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Discussion Starter · #18 ·
Re: What do I need for a rebuild on my 350?

I'm heading into the garage for the night, but before I had a question or two about the electric starter. I would like to not put it back on.

So is there any major pro's or con's for not having one?
I know I'll need a plug for the hole. Would this one work?


It's honda model number is #32951-310-810

Also are there anywhere else I can get one?
 

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Re: What do I need for a rebuild on my 350?

Jason TEAM SHRALP said:
I'm heading into the garage for the night, but before I had a question or two about the electric starter. I would like to not put it back on.

So is there any major pro's or con's for not having one?
I know I'll need a plug for the hole. Would this one work?
No down side to getting rid of the starter.
If that piece plugs the hole and doesn't leak, then you're golden.
 

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Discussion Starter · #20 ·
Re: What do I need for a rebuild on my 350?

Not a lot of work done today but I know where and what I need to do next. I found my Clymer's manual, and read through about 60% of it. I'm going to see if I can borrow/rent the tools I need to get the oil filter off. Then I'll be into the bottom case and find out why the piston rod in the right cyilinder has about a half inch of play. The next two pictures do a poor job of showing the play. If you look close you can see the change in position.



Besides that what are these little blueish plasticish rubberish things. They are only on the two front outside posts.


Besides cleaning up the mess I've made over the last two days. I took the forks apart, finally something that doesn't look horrible. Not to say there wasn't anything wierd. One had fluid the color of taupe, and one had fluid a pink redish color. The seals look okay and there weren't any leaking fluid up the legs. Here is a photo of them taken apart and waiting for some fresh fluid.

Any tips with the forks? Seams pretty simple, but if there is any secrets let me have 'em.

Another thing I was thinking would it be a straight swap between a SL bottom case, and a CB bottom case? and would the top end of the CB fit on the SL bottom? The reason I'm thinking about it is the SL case doesn't have the starter hole, and I'm going to be taking it apart anyways.
 
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