Author Topic: Original camshaft ?  (Read 3095 times)

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Offline Hummel

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Original camshaft ?
« on: February 03, 2013, 04:30:46 AM »
How can I tell its an original camshaft I have in my cb750 1974 ? It have an mark saying " made in USA" isn't that strange sins it an Japanese bike ?

Best regards Tommy Hummel


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Offline Dream750

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Re: Original camshaft ?
« Reply #1 on: February 03, 2013, 05:33:36 AM »
Original Honda 750 K & F cams will be “R” marked next to the cam sprocket. I have several examples and seen them marked anywhere from R1 to R12.

Sounds like you have an aftermarket cam, do you see any other markings besides made in USA?


Offline ekpent

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Re: Original camshaft ?
« Reply #2 on: February 03, 2013, 06:09:50 AM »
Sounds aftermarket. What do the top of the pistons look like,are they flat or do the have a dome for more compression. If its apart I would measure their diameter to see if you have a big bore kit in there. Do the valve retainers look stock also. Pics are usefull and fun also.

Offline Hummel

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Re: Original camshaft ?
« Reply #3 on: February 03, 2013, 06:31:26 AM »
The pistons is 61mm in diameter and flat in the top. I Would try to take soms pics when I go to the garage again. Thank you


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Offline bwaller

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Re: Original camshaft ?
« Reply #4 on: February 03, 2013, 06:36:22 AM »
Cam is a Kenny Harmon "D" grind

Offline 74750k4

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Re: Original camshaft ?
« Reply #5 on: February 03, 2013, 09:01:03 AM »
That sure is a KHD. Which would make that cam a re-ground Honda part, since it has that R1 mark too!

I'm installing a KHD (from Dynoman Perf) in my 74' engine right now, with 78' P/C, 392 head, Kibblewhite springs, CycleX Superflow valves. Std. bore. Special head work, by Ken Augustine... http://www.motorcycle.com/how-to/modifications-to-the-henning-honda-cb500-14679.html

Anyone running a KHD out there? Would love to hear all about it!

Offline Dream750

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Re: Original camshaft ?
« Reply #6 on: February 03, 2013, 09:51:45 AM »
Guys, I apologize for any confusion on the Cam markings. :(

The intent of my post in reply #1 was to show the OP two different photo examples of cam markings and where to look. As these are two seperate 750 cams.

First photo: How an original Honda 750 cam is marked with the “R” number next to the cam sprocket.

Second photo: How aftermarket 750 cams are often marked at the end of the shaft as in my Kenny Harmon “D” example.

As a side note: My K/H “D” is a regrind and was originally a Honda cam marked R8 and does not have the “Made in USA” mark.



Offline Hummel

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Re: Original camshaft ?
« Reply #7 on: February 06, 2013, 09:27:53 AM »
Here are some Pics. Can you say something about this cam! At the end it say ANDRWD

Offline scottly

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Re: Original camshaft ?
« Reply #8 on: February 06, 2013, 10:07:09 AM »
I can't see the pictures, but I would guess that is an Andrews "D" cam.

http://www.webring.org/l/rd?ring=thehondasohc4web;id=1;url=http%3A%2F%2Fwww.satanicmechanic.de%2F

Hmm, the link didn't work the way I wanted.. Anyway, there are specs for the Andrews cams on the santanic mechanic site...
« Last Edit: February 06, 2013, 10:09:52 AM by scottly »
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Offline ekpent

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Re: Original camshaft ?
« Reply #9 on: February 06, 2013, 10:12:53 AM »
My computer does not open the pictures either   :'(

Offline Hummel

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Re: Original camshaft ?
« Reply #10 on: February 06, 2013, 12:24:12 PM »
No my Picture uploader dosen't work. I will try to get that going later.

But Andrews D cam sound about right  :)

Offline Dream750

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Re: Original camshaft ?
« Reply #11 on: February 06, 2013, 06:53:52 PM »
This is how my 750 K Andrews “A” cam is marked and the “made in USA” is not present.

Other markings present are: C.M.C., C1, D1, 2187 and C1 once again. There is not any evidence of the cam being a regrind.   

Offline Hummel

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Re: Original camshaft ?
« Reply #12 on: February 07, 2013, 01:43:48 AM »

So this cam could be stock grind ? No performance at all ?

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Offline Dream750

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Re: Original camshaft ?
« Reply #13 on: February 07, 2013, 04:27:49 AM »
Your Andrews “D” looks right as they had the EP-13 mark and it’s a performance cam. ;)   

Offline ekpent

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Re: Original camshaft ?
« Reply #14 on: February 07, 2013, 05:03:44 AM »
I have an Andrews in an RC836 I did many years ago,can't even remember what it is anymore  ::)
   That aside though be sure to check what the valve lash should be set at. Without digging for my old instructions I think mine was to be set at .004 for both the intake and exhaust not the .002/.003 spec for a stock cam.