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Went Optima-hunting on ebay last week after I got my bonus from work, and, after being outbid by the same person twice, finally wrested this lot from his grasp:



One complete, scruffy, original Optima, and another basket-case that's missing a couple of suspension arms and dogbones, and has no wheels, tires, or body. I have the missing arms and (I think) dogbones. And of course repro tires and bodies are available, and I have my eye on a set of those Pargu wheels. So with luck, a bit more money, and a lot of work, I should be able to get a decent runner and a nice display model out of this bunch.

Be patient with me, this project is going to take as long as a Dickens novel...

Looks like a good score, any more pics of the complete Optima?


Keith

Sure, here are a couple body-off photos:





Obviously, this ain't right... even worse, whoever did it cut a big square hole in the hood of the body to clear the servo.
Have to find or make a servo tray, and get a repro body... but that's a ways off yet.



First, they both get completely torn down and cleaned up so I can assess the damage. I'm going to take my time with this one; I've wanted one since 1986.

Yep, that's definitely not right. The servo should be underneath the upper deck, double-sided-taped & zip-tied to a rather funky-looking servo mount that's actually not too hard a design to make your own. I did just that in my Barney build thread, using a piece of carbon fiber, some aluminum spacers and a bit of filing.

Make a list of everything you're missing, I can probably hook you up with some of the parts you need. PM me if you're interested. Good luck with the rebuild(s); I see the complete one has a bent bumper brace so the chin skidplate is possibly bent, too. Other than that, with some new parts & wheels, it should come out quite nice.

Thanks for the offer! I'll have a better idea what I'm dealing with after I tear into them a little bit. I plan to study the manual, and build threads, and compare them to what I've got. I've admired these cars from afar for years, but never actually had one, so I'm still at the bottom part of the learning curve. But that's what makes it fun, right?

Can't say I've seen the steering servo mounted that way before but it would be more stable than with the standard double sided tape and zip tie, looks like there wouldn't be much clearance from the body though.

For my runner Optima's I intend to try making up a more secure steering mount system that keeps the servo in the original position under the top plate, I never really liked the "tape/zip tie" method.


Keith

The thing that bugs me about the Optima servo mounting system, and probably the reason why you have to mess around with servo tape & zip-ties, is the positioning has to be almost perfect BEFORE you secure it into place. That little oblong hole in the top deck doesn't give you a lot of breathing room, and depending on the size & shape of the servo, your position will always be slightly different. Installing the steering servo was always a pain in the ass with the Optima series, and that's why that guy got lazy and Mickey-Mouse'd a simpler solution--but it's certainly no good if you plan to mount the original body, obviously.

Had to see how it ran before I tore it down. So I stuck in a known good receiver, swapped out the tires for a set of HPI rally car tires (the original Sand Supers hadve been worn down to Sand Not-So-Great-Actuallys), and took her for a spin, dust, grime, and everyhing.







Not bad. I can see why these were such good race cars in their day: they handle and steer really nicely. Suspension works really well on rough stuff. It seems to have some drag in the drivetrain, I'm not sure if that's a chain-drive characteristic of if there's something wrong. Well, I'll see what happens when I crack it open. Next time it sees the outdoors, it'll be a whole new animal.

You think the suspension worked well with those red shocks, you need to upgrade to a set of Kyosho Golds. Among the smoothest-performing shocks ever made for offroad buggies. As far as drag in the drivetrain goes, the Optima had a pretty good system. Where I've found drag is after bolting on the wheels tight; I highly recommend shims as the wheels' bearings can bind up when tightened with no shims or the wrong size of shims. Test that easily enough by spinning each mounted wheel after removing that corner's dogbone; it should spin smoothly. If it doesn't spin smoothly after bolting on a wheel, then the bearings are binding up because of pressure on the wrong area of the bearing surface. Other things to look out for: the little protective plastic sheet on the chain-guide covers was sometimes left on when people built the cars, and that thin plastic sheet ended up in the gearboxes. Lastly, a torquey motor that's difficult to spin by hand may make the car seem to roll with friction, but once the motor's fired up, it runs fine. That's easily tested just by removing the pinion gear and seeing how the rest of the drivetrain rolls. Lastly, you might end up opening your diffs up; they were very low-maintenance and very unlikely to get dirt inside, but I've disassembled scratchy-feeling diffs to find almost no grease inside.

Good luck with your rebuild!

Looks good. I've got a few sets of "Sand not so greats" here too.

I'd say the chain might be a bit lose or it could be stretched and need one of the links taken out.

Edit: Or just try what what Coelacanth said, his advice is probably more accurate than mine. We must've posted at the same time.


Keith

It makes me wonder if those original kit tyres were ever suited to any track surface. Maybe sand?

I have numerous Optima projects winding up right now and I still like them all. Glad to see more interest up here in these old gems.

Well, wherever the drag is, it won't be there after reassembly, that's for sure. I know it isn't the wheel bearings, because they're so loose they wobble a bit (and yes, they're bearings and not bushings; I checked). But if those bearings are that sloppy, I can only imagine how much wear is in the rest of the drivetrain. I'll find it. Restoring these things to perfect mechanical function is my favorite part. I may be lax about originality, and my paint jobs are laughable, but I build a mean gearbox. I'll get it right. I even found a new set of plastic gears in a box of random parts, so by the time I'm done it should be silky smooth.

And this one is staying with red shocks, for looks. But the other one, which will be more of a "bitsa" anyway, will probably get a set of Duratrax golds that I have on hand. I know about the Kyosho golds; I have a really nice Mid with them, and ages ago I bought a used Ultima (or Outrage, I forget) that had a set on it.

Teardown begins this evening, and I'm going to order a SS screw set and some new bearings soon. I'm also going to experiment with a brushless-motor 5mm hole pinion gear for the final drive gear; I saw in another thread that no one wants to be the guinea pig. So I'll try it, with a used diff gear first, just to test it out.

Good on you for experimenting with the top gear! Anxious to hear your feedback, as I have been thinking about it too. My ultima nd outrage are assembled with the plastic top gears right now, and I have yet to have any issue. I was waiting for a failure for an opportunity to upgrade.

Coelacanth wrote:the little protective plastic sheet on the chain-guide covers was sometimes left on when people built the cars, and that thin plastic sheet ended up in the gearboxes.

Ha! Just took the cover off the lower chain guide, and lo and behold: a crumpled-up piece of blue plastic film, all wadded up inside the chain guide. Didn't make it as far as the gears, I don't think, but good call.

markbt73 wrote:

Coelacanth wrote:the little protective plastic sheet on the chain-guide covers was sometimes left on when people built the cars, and that thin plastic sheet ended up in the gearboxes.

Ha! Just took the cover off the lower chain guide, and lo and behold: a crumpled-up piece of blue plastic film, all wadded up inside the chain guide. Didn't make it as far as the gears, I don't think, but good call.

The part I left out was that *I* made that mistake with my first Optima build. But in my defence, I've seen it at least a time or two since, so I wasn't the only idiot!