Project ecloptima (a Kyosho Optima restoration and upgrade)

[ecloptima]

I am restoring my old Kyosho Optima and adding the upgrades that I could only dream of back then. I'll track the process here. I hope you enjoy!

I am lucky that I decided to keep this car as I almost sold it back in the early nineties. Fortunately I changed my mind when the first caller called and told him "Sorry, it has been sold".

The car has seen gravel, tarmac, snow and carpet tracks in the past. It also used to sport a crude self made aluminum under guard and a (self made) metallic motor guard. Still the bottom chain guide has a 1 cm crack. Otherwise the car was in a very good shape and very clean when I "discovered" it again.




The above two photos are from the late nineties and it's easy to see that digital cameras weren't very advanced yet...


The front has suffered a heavy collision which destroyed the bumper and bent the under guard and here you can see how the front "bulkhead" sits on the guard.

Also the rear damper stay has been bent in a crash and it's not 100% straight.
I don't know if it was common, but this Optima came from the factory with Turbo Optima style longer shock stays. Though Turbo Optima was definitely not yet released when this was bought.

Damage report at the project start:
- Oddly the stock engine has rust inside and does not work
- The stock speed controller is broken
- Front bumper is gone
- Under guard is bent
- Differential ball bearings are broken
- Stock shock clamps are broken
- Chain guide has a crack
- Drive chain is stretched
- Steering servo status is unknown
- Receiver status is unknown
- Radio controller status is unknown
- Battery is dead
- Battery charger is unusable
- Original Sand Super tires are very worn
- Various scratches etc.

Project goal:
I always liked the Optima Pro body and I always wanted to have an under tray so basically this car is going to be reborn as an upgraded Optima Pro.
The car is going to be a shelf queen for most of the time, but occasionally a runner.
Main upgrades will be a belt drive (how unusual...), gold shocks and various carbon fiber parts. I have not yet planned how to attach LiPo batteries or what kind of upper plate I'll create.
I also have no idea yet what kind of electronics I'll be putting in it. However, the battery, motor and speed controller no longer work so there is "no limit" what to put in it. It will never be a racer though so I am not interested in any super mega turbo motor etc. upgrade.


This is how the project looked before I decided to go for belt drive etc. instead of the stock looks.


Here is the original body cleaned.

The currently missing critical item for the project is the rear belt *gear* diff. I'd like to use the original gears instead of a ball diff.
Also the design (so I can cut it out from CF) of the longer (early Optima Mid?) front damper stay interests me, but is not critical.

edit: minor rephrasing

[keithrc]

Nice project, I wish I still had my original Optima. You could probably straighten out your lower guard a bit more in a vice so the bumper brace doesn't bend.

Most of the things you mentioned in your damage report are very common.


Keith

[ecloptima]

Yes, I will try fix the front guard better before actually screwing it in place.
The photos show the results of my attempt to fix it in the 80's which wasn't so great

[terry.sc]

I don't know if it was common, but this Optima came from the factory with Turbo Optima style longer shock stays. Though Turbo Optima was definitely not yet released when this was bought.

It was standard, Kyosho supplied all the flat metal parts in a single parts bag, and rather than produce different parts bags for each kit they just included the changed parts with the Optima. The change came about around the introduction of the javelin, and Kyosho coming out with the gold shocks as an Option House part that were later included in the Turbo Optima.

Most breakages you list are pretty common, especially broken shock collars. Recently a complete set of new red shocks sold on ebay for £145. Most other parts come up regularly, but unless you want absolutely perfect new items the prices are usually pretty reasonable.

I also have no idea yet what kind of electronics I'll be putting in it. However, the battery, motor and speed controller no longer work so there is "no limit" what to put in it. It will never be a racer though so I am not interested in any super mega turbo motor etc. upgrade.

My runner Optima runs a 13 turn brushed motor in it, plenty of speed and the Optima easily handles it.

The currently missing critical item for the project is the rear belt *gear* diff. I'd like to use the original gears instead of a ball diff.

Easy to find, it's the same part used in the Optima Mid.

Also the design (so I can cut it out from CF) of the longer (early Optima Mid?) front damper stay interests me, but is not critical.

If you mean this one.

that is a part made by Parma, not Kyosho. The Mid part is very different. To make your own is simple, the bottom part is identical to the standard Optima part, all you have to do is mount a shock on the arm and measure how much taller you need to make the mount. If you are planning on mounting the shocks more vertical then I would suggest getting a pair of Mid wishbones as well as the wishbone mounting point is in the correct place. With standard Optima wishbones most tried using the anti roll bar mounts which meant using much stiffer springs to hold the front end up, usually ending up drilling a new hole in the wishbone roughly where the shocks mount on the Mid.

[Coelacanth]

I am restoring my old Kyosho Optima and adding the upgrades that I could only dream of back then. I'll track the process here. I hope you enjoy!

Also the design (so I can cut it out from CF) of the longer (early Optima Mid?) front damper stay interests me, but is not critical.

Although partly obscured, here is how I designed my own front shock tower out of 3mm carbon fiber so that my Barney Optima could take the rear Gold shocks instead of the much shorter fronts. I simply screwed the original Turbo Optima front shock tower on a piece of card stock (cereal box cardboard, I believe) and extended the uprights to where I could mount the longer shocks, after test-fitting & measuring with mock-ups several times. I chose to install it behind the original shock tower using screws that were 2mm longer, figuring that might help with structural rigidity.

Probably a bit overkill to use rear shocks on the front, but that was the purpose with Barney...it's a beast.

http://www.rc10talk.com/viewtopic.php?f=30&t=21530&start=92

[RichieRich]

This should be fun. I always had a love/hate relationship with the Optima. When working properly, this car was awesome. When something went wrong, it required hours of wrenching.

[Coelacanth]

That's true, the Optima didn't lend itself to easy maintenance, for sure. But then again, most 4WDs would probably be in the same category.

[ecloptima]

Thank you for all the comments and info!

Nice project, I wish I still had my original Optima.

Where did you lose your original Optima?

Recently a complete set of new red shocks sold on ebay for £145. Most other parts come up regularly, but unless you want absolutely perfect new items the prices are usually pretty reasonable.

I thought about new reds and even fixing the clamps, but I ended up acquiring a nice set of Gold Shocks.

My runner Optima runs a 13 turn brushed motor in it, plenty of speed and the Optima easily handles it.

Good to know. I think though that I would like to use a modern brushless motor to make my old Optima happy with new technology.

The currently missing critical item for the project is the rear belt *gear* diff.

Easy to find, it's the same part used in the Optima Mid.

At the moment I can see only (Optima Mid) rear ball diffs on ebay so I am waiting for a gear one to appear.

that is a part made by Parma, not Kyosho.

Yes, that is exactly what I have in mind. I saw this kind on Pargustore and thought it was maybe a repro of an Option House upgrade.
Can you tell me the height of this shock tower so I can make a more "authentic" copy?
Do the W-5001 short gold shocks fit this one nicely or do I need "medium" golds?
Thanks for the suggestion of using Optima Mid wishbones. Are they direct replacements of the original Optima arms?

Although partly obscured, here is how I designed my own front shock tower out of 3mm carbon fiber so that my Barney Optima could take the rear Gold shocks instead of the much shorter fronts.

Heh, yes a bit overkill I guess. I've read your Optima project threads and very nice work.
Thanks for the info on how you made the shock tower. I haven't received my carbon fiber sheets yet and I've never cut carbon fiber before so it will be an interesting task.

Regarding Optima in general I remember my friends had to replace their gears at least once in their for example Tamiya (Hot Shot) and Marui (Ninja) cars while my Optima still has the original gears in excellent shape. Less maintenance in Optima, but I always had to adjust the chain.

[keithrc]

My original Optima was sold to a friend back in '90/'91ish along with my Optima Mid and Lazer ZX, he still has them and wants to keep them. I'm OK with that though, they're in good hands and I have my own collection now.


Keith

[Coelacanth]

I haven't received my carbon fiber sheets yet and I've never cut carbon fiber before so it will be an interesting task.

Here are some tips that worked for me.

With your cardboard template (or original aluminum part if you're just doing a copy) screwed onto your piece of CF, drill your first hole where an existing hole is. Making sure the second hole-to-be is lined up, drill that one. Now with those 2 holes drilled, screw the 2 pieces together to prevent the CF piece from moving under the template/original piece. You can now easily drill all the other holes.

Next, I usually cut the easy straights with a hacksaw and fine blade, 24 or 32 teeth per inch or something.

I sometimes drill holes on inside corners to make it easier to use a Dremel cutting wheel to reach those places without cutting too far.

I then use the Dremel to cut the rest, always erring on the slightly too big side. I use either the cutting wheel or one of the round grinding tools to match the CF piece to the edges of the template/original piece. Once the part is cut free, I use round or flat needle files to better align all the screw-holes, straighten the straights, curve the curves, and round over the edges.

When you're happy with the piece, wash it, let it dry. I then use a Sharpie to color the cut edges black. When that dries a few minutes later, I treat the edges with CA glue, which prevents delamination and in combination with the black Sharpie ink, makes nice, glossy black edges.

[terry.sc]

that is a part made by Parma, not Kyosho.

Yes, that is exactly what I have in mind. I saw this kind on Pargustore and thought it was maybe a repro of an Option House upgrade.
Can you tell me the height of this shock tower so I can make a more "authentic" copy?
Do the W-5001 short gold shocks fit this one nicely or do I need "medium" golds?
Thanks for the suggestion of using Optima Mid wishbones. Are they direct replacements of the original Optima arms?

Can't help with measuring the shock mount, it was replaced with the kit one years ago. I have attached a couple of pictures I have of alternative mounts, they should give you an idea of size. You definitely need the short gold shocks, the mediums are way too long to fit.

67_1_b.JPG (22.07 KiB) Viewed 3927 times

67_1_b.JPG (22.07 KiB) Viewed 3927 times

optima shock mounts.JPG (21.05 KiB) Viewed 3927 times

optima shock mounts.JPG (21.05 KiB) Viewed 3927 times

The wishbones started on the original Optima with the thin ones, they were considerably beefed up on the Turbo Optima and shock mounting points were added even though the kit still mounted the shocks on the uprights. For the Mid the only change in the whole suspension from the Turbo Optima was to add an extra shock mount and the front anti roll bar mount. The rear suspension was moved to the Mid with no changes.

Regarding Optima in general I remember my friends had to replace their gears at least once in their for example Tamiya (Hot Shot) and Marui (Ninja) cars while my Optima still has the original gears in excellent shape. Less maintenance in Optima, but I always had to adjust the chain.

The only weak spot in the Optima is the final pinion gear, the kit soft alloy one wears quickly but if it is replaced by the hardened pinion, or the Ultima layshaft with a plastic pinion, the drivetrain is pretty indestructible.

[ecloptima]

My original Optima was sold to a friend back in '90/'91ish...

Great that you can still visit your original Optima

Here are some tips that worked for me.

Thanks for the tips! Highly appreciated.

Can't help with measuring the shock mount, it was replaced with the kit one years ago. I have attached a couple of pictures I have of alternative mounts, they should give you an idea of size. You definitely need the short gold shocks, the mediums are way too long to fit.

Thanks, good to know that the short gold ones will fit nicely.
When I get to the point where I have attached the front arms and shock mount I'll see if I'll design my own shock mount or copy an alternative mount.

The only weak spot in the Optima is the final pinion gear, the kit soft alloy one wears quickly but if it is replaced by the hardened pinion, or the Ultima layshaft with a plastic pinion, the drivetrain is pretty indestructible.

Yes, mine look worn as well. For the restoration I have the W-5040 Torque Limiting Clutch and UM-1 Counter Gear so it should be fine.

I hope to get some progress soon and some photos to post. So far I have pretty much been able to just wash the new lexan body

[ecloptima]

A bit of progress finally!


Disassembled the original chain drive diffs and washed off all the old grease. Added the diff gears inside belt diffs and greased them with new silicon grease. Added ball bearings too.

Parts:
SG-25 Sprocket set
OT-89 replacement TRTB080 240XL belt
Avid metal ball bearings

Next up is creating some carbon fiber parts so I can proceed to page 8.


I ended up "designing" a new front shock mount using Optima Mid's front shock mount as a measurement template for the height. The cardboard demo shock mount looks about right and I am looking forward to testing it to see if it is a good design.

update: parts list

[Coelacanth]

Cool. My concerns with the original Optima front shock tower design is the narrow piece that bridges over the gearbox. Fabricating your own extra-tall shock tower could put extra stress on that thin bridge piece. One idea I had was having a similar connecting bridge joining the tops of the vertical parts; that would certainly make it strong enough, but now you'd have to find a way to get the front of your body to fit inside the "hole" between top & bottom bridges. However, after I cut and mounted the piece I made with 3mm carbon, I found it to be very rigid & sturdy. You may not need to worry about it if you're using normal-length front shocks.

[ecloptima]

I thought about the same too and I also plan to use 3mm carbon so I guess it should be fine.
There really is not that much room to enhance the design