CB750K2 engine rebuild - valve springs

[philward]

H guys
Posted a longer version of this post last night but can't find it!
In short building the motor from the best of two engines. One of engines is from America via DK. On stripping valves and springs from American engine (Early K1/2 I think based on schematics because no engine number - previous guidance from forum members suggested cases replaced under warranty due to the chain snapping problems on early models), the valve springs are triple springs! An inner, outer and flat spring that fits between inner and outer. They are slightly wider/higher and the collet retainers are heavy duty machined items when compared to the standard thin retainer.
Can I use these springs with standard camshaft/engine (except standard compression 836 kit)?
Any help appreciated. Still can't upload pics because can't make them small enough.
Phil

[hairygit]

Without seeing a pic or 2 of them, I couldn't say for sure. That said, if the spring seats look the same as standard, I can't see any reason why not. Sounds as if the American engine has had some tuning work done to it at some time in it's life, be curious to find out exactly what has been done

[fisjon]

I had a CB750K1 back in 1972, they did snap chains from time to time and I had one shoot past my leg and wrap itself around the frame. Some did smash the cases up so there will be some around that were replaced.
My engine was one of the ones with the faulty gear selector barrel and it shot out of gear at about 95mph on the M4. The needle on the rev counter went off the scale and it caused internal damage. Honda striped it once as it had only done 900 miles but I wasn't happy with it so I stripped it myself a couple on months later to find they had not changed the cam chain and it was knackered.
The thing is I don't remember there being three springs on the valves, just an inner and an outer. In fact I haven't come across that on any of the Honda fours.
By the way, (in case you are not aware) the inner springs are graded (one end is more tightly wound than the other) the tightly wound end should be fitted nearest to the cylinder head. A lot of the engines I have worked on have the springs just put in willy nilly.

[philward]

It did have a high comp 836 kit on - only discovered when I got the other newly bored barrels back and thought I'd see how much bigger the new bore was to std pistons - only to discover they fitted straight in!
I'll compare cams and see if there's a difference.
If the springs are just a heavy duty (American) aftermarket set, what effect will they have on normal riding - the bike won't be used hard (got other bikes for that). I do understand the advantages of heavier spring when used at high revs but will they impact on low speed running?
Would buy a new set but spent a fortune on new parts for engine already.

[hairygit]

Won't affect normal running if used with a standard cam, just gives the extra protection against valve bounce if you miss a gearchange at high rpm

[philward]

Here's a pic of valve spring - standard and triple (hopefully pics load)