Turbo Optima build - Project Barney: Finished

[Bormac]

Yet again another Super Optima project you have got going there Marc. I am really looking forward to seeing this one on its wheels.
Great job so far.

[Coelacanth]

Thanks for the comments, guys.

the first option doesn't look like a good all-rounder to me. The goosebumps and responses look as if they'd be better suited than the calibers for the kind of debris you 'd encounter off-circuit. Just going from looks though: I have no experience with any of them.

The LHS near my work had the wheels I was looking for and the Calibers, they looked pretty good. I picked them up mainly because they were in stock and a decent price--$12/pair. I'm keeping my wheel choice under wraps for now until I can confirm fitment.

Which car are those alu carriers and steering knuckles from?

Those are Lazer ZX-5 knuckles; originally anodized a nice royal blue. I used a similar set for CYANide, made by 3Racing. The quality wasn't as nice but they were a more light blue color that matched better. I can't remember the manufacturer at this time but I'll check my header card collection later--these royal blue units are a perfect swap for the Optima knuckles; the 3Racing ones needed some filing down of the screw-hole bosses on one side. The rear carriers I bought from EvolutionRevolution here, they were originally blue too. I'll PM you the part numbers when I'm back home and can check the cards.

EDIT: I tracked down the knuckles I'm using, but didn't get them from Tower as Tower was too expensive and wouldn't ship economically either--they're actually made by Duratrax, part # DTXC9953:

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXSD47

[mrlexan]

Purple is awesome. Post pics when you have it done. I've got purple custom ano piece here and there on my DH bike, frame is lime green.

[Coelacanth]

I've had so little spare time lately, but at least I put together the shocks. I can't do a whole lot more until my screw set arrives.

[jwscab]

are those the shock washers up there anodized blue?

Looks good.

[Kayne]

Those look cool.

[EvolutionRevolution]

Wow. Those look psychedelic.

[Coelacanth]

are those the shock washers up there anodized blue?

Looks good.

Green, actually...the same color as the shock caps & other green parts. They're working out great, thanks for making them, Joe! I'm actually going to need your help for some custom wheel washers--the narrow crawler wheels I chose for this build have an adapter for 5 or 6mm axle holes, but I'll need an adapter with a 4mm hole drilled through it...just a simple 1mm thick washer with a 4mm hole through the middle. I'll be in touch later.

[jwscab]

sounds good!

wow, that's weird, that flash really makes the color look blue, or a guess like a turquoise. Very cool all around though!

[Coelacanth]

Put together the rear control arms, which began life as a $6 pair of cheap alloy GPM arms. They're about 5mm longer than the stock arms, hopefully a bit wider track and some wheels with a bit more offset should improve stability & cornering. The picture of the unassembled arm parts shows the actual colors...I'm not sure why some of the pics taken with the same cam kind of give everything a sepia-tone, slightly yellowing the green & pinking the purple...

[Coelacanth]

Here's a mock-up of the front arms...I'm awaiting an alloy part to upgrade the C-carriers. I found these cool aftermarket upgrade arms that are a full 20mm longer than the stock arms, pin-to-pin. However, the functional length--where the hubs/carriers are--is exactly the same. The aftermarket arms have a much deeper notch for the elongated C-carriers than the stock carriers. The aftermarket carriers have camber stops.

A technical question for the physics/racer gurus: what are the differences or advantages of going to arms that are 20mm longer but using elongated carriers and keeping the wheels in essentially the same position?

[Mr. ED]

I like those front arms! Those longer arms will give you the same wheeltravel for less angle change of the arms.
They look very much like kyosho originals, bit like the maxxum front arms too.
Personally I'd go with old lazer front and rear arms though: to apply the same technical principle in the rear and get a consistent look. Just a suggestion.

[Jay Dub]

These do look like the maxxum arms ( I have 6 sets if anyone wants them ). Anyways, The longer arm (as previously stated) will give you the same travel, with a lower angle change in the arm. Or it will give you the same angle, with more travel -depending on setup. There is actually alot going on there. Originally it was designed to reduce tire scrub, but eventually it was realised that having the lower arm pivot reach past the upper pivot point made the front end less supple in rough corners, and made the car roll over more easily when bicycling or getting chassis high in corners. So, through trial and error it was realised that a car with ball pivots for both axis (think Pro Radiant or Schumacher CAT was a a better compromise. And better yet a car with the king pin axis slightly out front of the hinge pin axis (Losi XX4, Kyosho ZX5 FS, B44, etc.) made the car much more stable in the rough. So the idea is to have arms that are the "correct length" and as long as possible, instead of just plain long as possible. -Jeff

[Coelacanth]

These do look like the maxxum arms ( I have 6 sets if anyone wants them ).

Thanks for the info, guys. Here's a pic from the seller, referencing bag number MX-6, which would seem to indicate a Maxxum part. The seller wrote "Kyosho Optima Front A Arm Set Strengthened" so I assumed he knew what he was talking about--fortunately it makes a perfect swap!

[Coelacanth]

Got a couple new belt diffs built from a NIP SG-25 sprocket set, buttery-smooth with new Revolutions bearings & Duratrax chrome outdrives.