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Hello all, I am new to these forums, an avid vintage collector and racer of modern and vintage models, I am currently finishing a restoration/build of a Hotrick Converted Optima with many option parts.

I intend to race it amongst current models and as such it needs to stand up to the rigours of modern racing, I have a history of racing my vintage models, some say I am mad for giving some of the models a good thrashing as I race them hard, they were meant to be raced wern't they?? however I do also have some shelf queens that I keep nice.

My question is this .
What method of a durable/consistant slipper clutch has anyone found to run on the 1st series optima's.
The slipper in the counter gear from the Turbo Optima is not man enough as standard, I have worked tirelessly to achieve a strong and consitant slipper with the counter gear slipper and with alot of modding feel I have achieved it, however I just want other optimaniacs ideas?
I wouldn't like to enter a meeting with it and go home early becuase it can't handle the power.
I can run a solid transmission as the car is still running 32dp all through and will be bullet strong , just wanted some sort of transmission saving device when landing those large flights.!!

I have fitted the cover for the racing clutch pinions if required and have a few, yet have not tried to run one, are they any better? anyone used them in earnest?

The car is running lipo and 5.5 brushless, I have tested it on grass tonight it handles superbly and it's so fast it's just crazy. It's really a weapon in red!!!! Can't wait to paint the body and go race it.

I will post some pics soon.

Steve

hello Steve,

I haven't found a slipper for the optima. I was going to modify the slipper unit from the early cars, but the shaft was too fragile and the threaded part broke off.

I was going to sandwich the gear between 2 friction discs and use a heavy spring to control the tension. My only real concern would be the heat that's generated from the setup...as it may melt the gear. I guess if it were adjusted correctly, it wouldn't be too big of an issue.

Your other "option" would be to use the parma slipper kit...which was attached to all 4 wheels. Each wheel would slip. I think there's a kit on ebay but it's for a rocky...should also fit the optima.

Regards,
highwayracer

I'm affraid I have no immediate solution either, and some bad news on those slipper pinion things.
Though I haven't tried them myself I've heard enough testimony to not go there.

IF you're handy and willing to mod your car beyond made-to-fit: I've been playing with the idea of using a triumphs rear tranny and a lazers front diff. The belt to the front could run over the top shaft only, diff only, or diff and topshaft: depending on the length of belt you find and the layout you prefer.

Otherwise... beltdrive conversion and loose ball-diffs

All good stuff guys.

Never come across the parma kit before, can't find it either, can you post a link.?

I have gone down the route of friction pads concealed within the original layshaft slipper. It has been difficult to fit some in within the length of the original shaft and still get the nut on enough to really crank some pressure on.
Load's of pressure required due to the small diameter of the pads. I cut up some yellow Mugen 1/10th Gas car brake pad material which is very heat resistant/stable. They are bonded to the layshaft gear both sides so they don't slip on the plastic surface, but will slip on the plates I put on the outer side of the pads.

Not really wanting it to work as a modern slipper ie; for traction control. Just to save the tranny when landing, so really minimal slip required.

I've stepped away from some of my kyosho projects to work on some other "plastic" kits, but I have thought about this for some time now.

As my previous stated, I actually broke the original top shaft of my optima when I attempted to torque down on the nut that held the slipper in place. I plan to use a grasshopper/hornet rear axle to fabricate a new top shaft. It's the right diameter for the bearings, it's thicker and you can use a 4mm nut on it.

I've used these before to fabricate the top shafts on various projects that used 5mm bearings. I've mounted an a&l slipper on an optima mid numerous times.

Regards,
Roger

Stephen Lander wrote:Never come across the parma kit before, can't find it either, can you post a link.?

It was there for months but it's no longer on ebay. I guess someone finally bought it.

I think there's a pic in the scan section, but it is a stupid design

some guys used shumacher topshafts and slippers on their PB's

I recently machined up a slipper unit for my ultima, and it came out pretty good. I may do another for my optima project. I am planning to post pics of my "Ultimate Ultima" project as soon as I can get some time to vacuum bag a chassis, and finish it. The slipper looks promising, and uses some stock Kyosho parts for the slipper plates, and fiber washers. It may be a while, but will be worth the wait . -Jeff