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Discussion Starter · #1 ·
I just bought a '72 CB350 for my wife's birthday. The push rod was bent real bad and the seal was torn up. The piece behind the seal was also cracked and chipped (pic attached). I'm a mechanic but this is my first time working on a bike like this. My question is how bad is it that that piece is cracked, and how do I remove it?
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I just bought a '72 CB350 for my wife's birthday. The push rod was bent real bad and the seal was torn up. The piece behind the seal was also cracked and chipped (pic attached). I'm a mechanic but this is my first time working on a bike like this. My question is how bad is it that that piece is cracked, and how do I remove it?
It's not the greatest thing that the outer race of the small end mainshaft bearing is cracked, you could put a new seal and clutch rod in it and be okay. If you want to replace it (and you'll end up using a used one since new ones if available will be outrageous prices), the engine has to come out of the frame, flipped upside down, clutch cover, clutch, oil pump, shift shaft and alternator covers have to be removed and then the lower case to lift the mainshaft out of the trans and replace the outer race. The PO, or a PO before him, probably threw the chain and bent the clutch rod so bad it did that damage.
 

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I've torn down a lot of theese 350's and never seen damage like that. The end cap should look the picture. I'd be pulling the engine and doing as CTD suggests.
The other black piece in the photo is a seal retainer I made to prevent the seal from blowing out and dumping all the engine oil.... I now put them on every 350 I work on or build.
 

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Discussion Starter · #4 ·
It's not the greatest thing that the outer race of the small end mainshaft bearing is cracked, you could put a new seal and clutch rod in it and be okay. If you want to replace it (and you'll end up using a used one since new ones if available will be outrageous prices), the engine has to come out of the frame, flipped upside down, clutch cover, clutch, oil pump, shift shaft and alternator covers have to be removed and then the lower case to lift the mainshaft out of the trans and replace the outer race. The PO, or a PO before him, probably threw the chain and bent the clutch rod so bad it did that damage.
Thank you for the answer! It's been real difficult finding answers without knowing the proper names for everything. What would be the purpose of that part of the race? Just to keep the push rod better aligned and stable? There's no cracking anywhere else in the area. And I was hoping I could get away with the rod just being supported by the seal. It's not going to be rode a tremendous amount but it will be her first bike so she'll be a little rough on the clutch. I plan on putting all new gaskets throughout the engine. This is the old push rod which is absolutely being replaced.
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Thank you for the answer! It's been real difficult finding answers without knowing the proper names for everything. What would be the purpose of that part of the race? Just to keep the push rod better aligned and stable? There's no cracking anywhere else in the area. And I was hoping I could get away with the rod just being supported by the seal. It's not going to be rode a tremendous amount but it will be her first bike so she'll be a little rough on the clutch. I plan on putting all new gaskets throughout the engine. This is the old push rod which is absolutely being replaced.
You COULD get away with it, but it would be far better if you didn't. It isn't entirely about the clutch rod support, it could also allow some loss of oil flow to the bearing with a gaping hole like that but as I said, you could probably get by with light and infrequent use. That clutch rod is as bent as any I've ever seen and as Boomer mentioned, I've never seen a bearing outer that badly cracked either.
 

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Discussion Starter · #6 ·
I planned on doing a complete tear down, deep clean, and new gaskets on the bike anyways. I've got the clutch off already just trying to assess the damage. I'm good with engines, but like I said I'm new to working on bikes and it's definitely a bit of a learning curve. Knowing this damage, is there anything else I should watch out for going forward?
 

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I planned on doing a complete tear down, deep clean, and new gaskets on the bike anyways. I've got the clutch off already just trying to assess the damage. I'm good with engines, but like I said I'm new to working on bikes and it's definitely a bit of a learning curve. Knowing this damage, is there anything else I should watch out for going forward?
You need this. Honda CL350 SL350 CB350 Factory Service Manual.pdf
 
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