Help identifying the correct replacement intake valve

[jmw_lanc]

Hey, Hopefully someone can help me quickly...

I'm having trouble figuring out what is the correct intake valve to buy to replace a broken one.  My bike was a frankenstein machine with a 76 supersport frame, electrical and hand controls from some dohc year, and an engine with the model number cb750E 3052505, which I think means its from a 78 cb750k8?  I see on some websites listing new intake valves for the cb750k years 69 - 77, and then intake valves for years 79 - 82... but what about 78?  However, then I found on ebay an intake valve that is listed to be good for cb750k years 75 - 78???!  So I'm confused.  I already bought two intake valves which I thought were different but when they arrived they looked exactly the same.  And neither of them look like my valve.  My valve has a narrow grove in the valve stem for the cotter to grip inside the valve retainer.... both of the ones I ordered have a much wider grove in that place.  When I look at photos of valves on line, it seems like my intake valve looks like the ones for the 79 - 82 years (on partsnmore.com) and like the one I found on ebay for the cb750k 75 - 78...which also confuses me.  I would go ahead and buy the one I found on ebay but the conflicting information I'm finding online has me worried and I won't want to waste more money/time ordering the incorrect parts.  Any help with this would be excellent and much appreciated!

Thanks!

[TOOLS1]

You can still get the valves new from Honda, for $28.00
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[jmw_lanc]

Thanks for getting back to me but my local Honda dealer was unable to find the valves for this year and model.   They aren't made oem or aftermarket.  I always need the ' harder to find' parts for these projects!

[TOOLS1]

I thought http://www.powersedge.com/ was showing it, but I am not seeing it now.Your Honda dealer is either lazy, or don't know what they are doing. I'm lucky that I am close to a top notch dealer "Freedom Cycles" in Grandview, MO. They bend over backwards to find me parts that are unavailable, but are still in a dealers stock. Just awhile back they found, and obtained the very last NOS parking brake light switch in existence for a CB 750 A.
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[TOOLS1]

Here you go. Dynoman has them. You just need their retainers as stated in the listing. http://dynoman.net/engine/valves/index.html#sohc
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[jmw_lanc]

Hey thanks for your help locating these!
Hopefully the more bikes I rip into in the future the better i get at locating parts.  

[TOOLS1]

Here is something that might help http://www.cyclexchange.net/Engine%20Tech%20Tips%20Page.htm
I think if I were you I would find a 69-77 head, or complete set of valves with retainers/keepers from a 69-77 head.
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