Option house platinum shocks

[Jirka]

And there is one difference more to Gold or many other shocks: The rubber cap/diaphrams is different in front shocks and rear shocks. In rear the volume for air should be bigger. See pic below, rubber cap parts are N & O :

Jirka

[Lonestar]

So you're saying they're doing what they're intended to do to prevent leaking?

P.S. You previously said oil doesn't create stiction... Anyway, nobody really knows what the problem is, we're just giving ideas to help his troubleshooting.

silicon o-rings swell in silicon oil, then they become too big and put too much pressure on the shaft. Make that experiment, pull old shocks apart and compare then size of silicon o-ring with new ones, they're a fraction of a millimeter bigger, and way softer too btw which is symptom of them sucking in fluid in their structure and swelling... New, properly lubed with the right tribologic fluid (green slime) o-rings will not leak much (they always leak a bit tho), and as long as they don't start swelling and the shock shaft is in good condition, will stick very very little too (although zero friction doesn't exist).

The point I was trying to make is: too viscous an oil doesn't create stiction - too viscous an oil creates too much damping, and when piston movement slows down the damping is reduced. Unfortunately this is a common misconception on the rc forums, where a lot of times you can read things such as "- When I push down on the car the suspension won't go full back up any ideas? - Yes, try lighter oil".

I'm done now

Paul

[mrfoski]

Paul, I think youre right with the O rings, they do feel a little spongy. I'll try to hunt down some replacements. Surely there is a 'new' equivilent, rather than the original item. I'll post it here if I find it. Thanks everyone for the help, it's saved me a lot of time.

[DodgeDerek]

Sorry to be late to the party on this thread, but when I was Googling servicing these Platinum shocks, it was one of the first I found. Anyway, the o-rings were swollen and causing a lot of stiction so I wanted to replace them. I found a great replacement from DuraTrax, part number DTXC9289. Now my Platinum shocks are much smoother. Still not as smooth as some of the Golds I have, but acceptable.

Again, sorry to resurrect a year old thread, but I wanted to share what I found in hopes of helping anyone else in the same situation.

Derek

[Mad Racer]

Just thought i will share my recent experience with these shocks lately.

I rebuilt a set of Golds & platinum's not so long ago. All went well with fresh oil. All seem well with smooth action.

A few weeks on a grab my Mid Custom & noticed the shocks at the rear were sticking. This had me scratching my head as i new these were fine a few weeks earlier .

So a tear down happened last week and found that the piston was sticking. Was very difficult to push the shaft out. Once i did the piston was swelled . Never seen this in all my time in r/c. ( 30yrs Lol) I decided that the piston was too big to file down so new pistons went in. All super smooth now.

The old oil that the pistons have been in & than fresh oil must have caused a reaction with the nylon pistons too swell. That's all i can put it down too. This has happened to me with Gold's & platinum's.


I have never replaced any of my seals in my Kyosho shocks..

Cheers
Mark

[sundevil67]

What would you guys say is the closest modern example of the platinum shocks?

I bought a practically new Turbo Mid SE for $35 about 32 years ago ( ) from the kid up the block who really should have had a beginner car. Many years later I tore it down to rebuild/restore, but never got around to it. I'm in the process of digging out as many of the original parts as I can to see if I can cobble together a road-worthy ride.

Anyway, the platinum shocks are definitely not going to be able to be returned to functional condition. Used originals are just silly, so I'm wondering if the stock shocks for the Optima Mid '87 Worlds be a direct replacement for the original? If not, is there something else that'd be a suitable replacement (roughly the same color)?

[GoMachV]

Sorry I totally misread the question, yes the rere shocks would fit and work just fine

[terry.sc]

Depends on what you mean by a modern example. There aren't any modern examples of externally adjustable shocks as they were proven to be pointless being over complicated and never used for their intended purpose. While back then they were an alternative to keeping the same oil and changing the pistons to different hole sizes, while in reality you usually keep the same piston and change the oil to suit the conditions.

If you means just something that bolts on as a replacement, then the rerelease Mid ones you know are already the same length and have suitable springs available. If you want the oversize shocks look of the platinums then any big bore dampers will work. The Yeah Racing big bores are good value and listed by their shock length to easy to find the right ones.

[sundevil67]

Depends on what you mean by a modern example. If you means just something that bolts on as a replacement

Yeah, that's what I meant - one I can buy off the shelf today that doesn't require any modification to fit, and are also of a similar color. They are the only bits (as far as I know at this point) that will definitely not be original when I'm finished with the restoration. I'll probably use the carbon chassis & a few aftermarket options, but am going to try to stick to what was available at the time.