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I'm restoring a CB350 that had been sitting for about 20 years. The previous owner parked it as it was having problems with 2nd gear. He had bought brand new gears to replace them but never got around to it so he gave me them to me with the bike. According to him the engine was never apart.

I've replaced 2nd gear in the transmission - and will install a new cam chain as part of the build - and I'm now in the process of re-installing the crankshaft.

One thing I noticed is that the bearing on the stator side does not have a dowel, although there is a slot cut in the crankcase for one. Is this correct? The bearing that's in there is a KOYO 83442.

I have the Honda manual and it references dowels on the 2 center bearings and the the stator bearing

It's a K4, so the only thing I can think off is that sometime between the K0 and the K4 Honda replaced the caged roller bearing with a standard ball bearing. Is this correct? How does it get oiled...from the Stator housing?

If thats the case do you simply just bolt the crankcases together to secure it, or is it better to use a little smear of bearing retainer

Thanks, and sorry if these questions are dumb. Its my first time rebuilding a CB350 motor
 

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You are correct. There was a bearing change. No bearing retainer needed.

Check the shift drum carefully and also the shift mechanism on the right hand side. Make sure the retaining screw on the end of the drum holding the star wheel in place is tight. It loosens mostly on the K5 engines but I check every one I come across.
 

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Hi All. I have a related question. I'm rebuilding my 1972 CB350 motor. The bearings on the clutch chain side of the crankshaft. It's bearing #13 is the attached photo.

This rebuild started out as a task to replace the cam chain tensioner, which I thought was responsible for excessive cam chain noises. It was only when I took the engine casing apart that I realized what else was taking place. See the second attached photo.

What happened is that bearings in the alternator generator wore out and metal got caught up in the crankshaft bearings.

With the motor now all apart, my question is whether there's a way to take the bearings off and replace them individually? Or does one have to replace the entire crank shaft?

Any and all suggestions welcomed.
311186
311187
 

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It comes right off the end of the shaft, it may be a light press fit on the shaft, any decent machine shop will have the necessary tool(bearing separator) to get it off without damage. Take the #s off the outer race to any bearing supply house and they can order you a replacement.
 

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In all the 350 engines I've taken apart I have never seen damage like that to the crank bearings. As a matter of fact even in the roughest engines the cranks seem to be useable. I would suggest finding a replacement crank as the replacement of the center bearing requires the crank to be taken apart.
 

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Thanks for the responses. I think the best thing to do would be to take it to a bearing or vintage Honda specialist. However, should I need to get a replacement, is there anything in particular in terms of wear and tear that I should look out for in a new/old crankshaft? FYI - I'm in Toronto. Thanks again.
 

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The early cranks used different bearings that are easily identified visually so look for a crank like yours.
I wouldn't play around with it just find another crank. If you want to pay the shipping I'll send one of the three I have taking up space. I actually have 4 but one is a K1 crank and you don't want that.
I also seem to recall someone replacing these bearings and they turned out to be smaller even though the numbers matched.
 

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This is very kind of you. Yes, I would gladly accept your offer and pay to have it shipped to Toronto. My motor number is CB350e 4135081 if that helps in matching the crankshaft. Many thanks!
 
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