aluminum valve spring retainers

Hello everyone! While sorting through some old junk, I came across these aluminum valve spring retainers. Does anyone in this esteemed community happen to know which springs or what lift specs they are designed for? 

Look like pedestrian KZ650-750 SUB collars. Have you tried a correct shim to make sure it fits correctly? I wasn't aware these were available aftermarket but i don't do the smaller 650ish stuff? I see in the background you have what looks like an original steel one, just compare. They won't be stronger, just lighter.  

I have some exactly the same with the matching wider angled collets from the Orient Express drag bike. 
They fit Z650 through to GPZ1100.
You can use any cams or springs you like but they are meant for racing only and very frequent inspections for wear and cracking etc..
I opted to replace them with titanium ones for the rebuild as does everyone now so really only a vintage race item suitable for display .
Off the top of my head ally retainers were made by Web Cam, Denco and  Yoshimura.




 

Thanks for the reply, but it is specifically the aluminum valve spring retainers (and keepers) that differ from the standard ones—and they are very lightweight. I’m specifically interested in which valve springs can be used with them. 🤷🏼

Zed, thanks a lot for the reply. Great stuff, as always. 👍🏻 I have titanium retainers too, but these are definitely much lighter. I suppose they can be installed on a GPZ1100 camshaft using the stock springs? I won't be using them with .440" lift springs. Also, could you tell me what the compression ratio is on your bike with the Andrews cams?

I would only use those for display.
Titanium is the only answer for  a upgrade 
 

v.f. wrote:

Zed, thanks a lot for the reply. Great stuff, as always. 👍🏻 I have titanium retainers too, but these are definitely much lighter. I suppose they can be installed on a GPZ1100 camshaft using the stock springs? I won't be using them with .440" lift springs. Also, could you tell me what the compression ratio is on your bike with the Andrews cams?

I wouldn't use them in any engine now but if you did they would need inspecting very regular and i don't mean every few hundred miles but after every run or race..
You should put them on the shelf and use the titanium ones.
Non of my current bikes have Andrews cams.
They are Norris 407's and Kent 410's in the normally aspirated ones with 10.25 :1 comp and GPZ1100 Unitrack cams in the supercharged and Turbo bikes with 8:1 comp.

Спасибо за ответ. Коллективная мудрость — это замечательно! Пока оставлю их там — может, они пригодятся позже... 😂 Titanium is a pretty nasty material; I had titanium valves in my race bike, and after five runs, a valve seized in its beryllium-bronze guide and pulled the guide right out of its seat. That’s why I don’t like titanium.

Thanks, I'll put them back then. I just don't feel like dealing with all this anymore... 🤦🏻I was recently looking through the site again and came across an old post of yours where you mentioned running an Andrews X3 on the intake and another Andrews cam—but with less lift—on the exhaust (on a Kawasaki GPZ1150). I set my compression ratio to 11:1 and can't seem to get rid of the detonation. I’ve tried retarding the ignition and enriching the mixture, but I still get detonation during hard acceleration. It runs better on 100-octane fuel, but that’s expensive. I probably need to lower the compression ratio to around 10.25:1 to achieve a DCR of about 8.25:1.