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sohc cylinder head

TRO55

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Loris,S.C.
Are the sohc heads known to crack.I have a 76 F model and looks like a crack in the square well under the cam tower.Can it be verified somehow before proceding. Also I seen on this site that the F model motor # should start as cb750ef.Mine is cb750e-2529974.According to Carpy's site that would be a K model motor.My bike is original surviver.Someone enlighten me thanks.
 
No I have never seen a cracked sohc head. Take it to a machine shop they can detect cracks. yes you have a 76 K with that number. post a picture of the suspected crack
 
Thanks dirtdigger,I've never seen one cracked either,but hey its been 40 yrs.Just some thing to play with, but don't want to invest a fortune. Looking for a used motor now for the head and above. As far as Numbers this bike is original as it had all the yellow paint.I can tell the hardware never had wrenches on it.Are you meaning magniflux or something like it.Just got through the hurricane so will be wrenching soon.thanks 20190908_100640.jpg20190908_100605.jpg20190908_100458.jpg20190908_100749.jpg
 
Yes magniflux type testing. By that picture I do not think that is a crack but it could be. That is a supersport frame but those numbers on the motor are definitely a K motor See if you can find a 341 or a 392 cast or stamped into the head anywhere.
 
Yea DD, the head is 392 5X. I can see it has f model pistons in it.Saw another site that doesn't even mention FE motor.
 
It is a k bottom end or at least k cases with the f top end then so its been apart at some point.
 
checked out Honda chopper.com production timeline.My take is it could be E. Don't know y I really care, just get some parts and fix it.Just cant believe this was apart.20190814_111333 (1).jpg
 
hey thanks MB,my take is only those 4yr f models would have other than E.It says F,FE,or E. So now,I'll be needing F Camshaft and set of cam towers.
If anyone has good ones I could paypal for them. thanks all for the help.
 
Technically there is no such thing as "magnaflux" testing. Magnaflux is a brand name, not a method of NDT (Non Destructive Testing), the word is commonly used I know, but its not accurate, and often referred to when in reference to magnetic particle inspections. A aluminum head wouldn't be able to have magnetic particle done anyway (for obvious reasons) instead you would use florescent particle or Eddy Current.
 
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