81 cb750c need help

[Chad Walker]

I have an 81 cb750c I have had this bike for a couple of years. Last year the timing chain broke. The long one that runs from the crank to the intake cam. When we disassembled the engine to replace it we discovered that the chain guide had broken and wrapped itself around the teeth on the crank and broke the chain and unfortunately two teeth off the cam gear. My buddy thinks we can put it back together and it will be ok since the teeth that are broken are not right together. Should i put it back together and take my chances or should I get another crankshaft?

[Polymer-2]

Unless you just need practice rebuilding engines I'd fix it while it's apart.
If you don't every time you ride it you will wonder "is this the day it will break?".

I don't know which ones interchange but here are some on evilbay:
1981 CB750 C

1979 Cb750

1981 CB750 K

There are many more. Just search CB750 crankshaft

[Chad Walker]

Yeah I thought so. I have a crankshaft on the way it's from an 82cb 750c with less than 8200 miles on it. I hope it will work.

[Polymer-2]

Looks like 79-82 C, K and F crankshafts are the same part number.

[Chad Walker]

Well that's good, but my buddy said something about the bearing codes, apparently they differ form engine to engine.

[Polymer-2]

Same part number = same part. He may be referring to a crankshaft that has been turned aftermarket and requires undersized bearings.

[OTTODOCTOR]

   OK -OK- So I was just a little late , but it seems there's plenty of good advice from the gang ! --  Cranks are plentiful on ebay , and fairly inexpensive . Ask yourself this question . " Do I want to tear it down again ??" -- Sorry for being behind the curve guys .--