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Build Thread My Ultima Pro (re)Build Thread KIT NO.3117 from 1989 ish.

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I also used Koswork axle shafts on my Mid. I ran into the same problem.
I used Koswork +2mm hexes and hardened axle shaft pins. Everything fit together perfectly.

https://koswork.com/portfolio-item/...-4-for-ot231-mid-turbo-optima-javelin-ultima/

https://koswork.com/portfolio-item/...-wheel-hub-mid-turbo-optima-javelin-ultima-2/

They have +1 and +2mm hexes avail. 😎
I just wish they would have offered them with or without the pins, then I would have ordered them with, I was flying blind.

I put in a regular pin just to see if they would fit and they fit but those would not be fully functional and nothing to hold them centered. I'm trying to come up with something creative, another two week + wait is not going to get me racing in a couple weeks.

I'll head over to the track soon and see what they have. I have to get me some slicks to put on this for the track anyway, they may just have something.

Just now searching for Koswork resellers I see A Main carries their stuff, mostly, not the pins. I did see the optional widths. I may order me a set of +2s just because it would assist wheels with the wrong backspace. Would be good to have options.
 
Kyosho OT231 might fit and work well. I have not tried it yet. Might be faster than Nick.
I can confirm ZERO slop once my hex andbpin were installed. No shims, it just fits. ❤️
I am MORE than happy with my Koswork parts. I have special ordered from him, waited over a month and still found the quality and fit are well worth the wait.
Jcracingproducts.co.uk allso offers some nice axles. They sell some cool adapters if you ever want to put a set of Yokomo wheels on it.
They sell propper Kyosho looking wheels that won't need backspacing to fit your vintage buggy.

I have also seen a Kyosho12mm +1/+2mm hex. Depends on how its facing when its mounted.
My phone must need coffee. I can't find them in a search right now.
 
Turns out with those new axles I can cobble together something that is perfectly operational. I'll order me up some of those correct pins but this solution should work just fine to get it rolling. Charging a battery to give it a test spin. Not sure what these hubs were specifically intended for, but fairly common and I have a pile of em. Probably axial things but they are fairly standard and work just fine. The pin size is obviously a standard so the pins I have on hand for these hubs are just right.

I had to use .9mm of shims on each side which is what I used on the stock axles. The new Koswork hubs will be used when I get the appropriate pins.

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Ha! I like the fireworks display and my new hat, although it is only 10 pm here. Happy Fourth of July folks!

I just got done taking it out for the very first rebuilt spin tonight. I'm quite tickled. I have a nice smooth flat roof over my garage which is a good place to spin a couple doughnuts.

Gotta say, nice seeing it do it's thing to just a small degree. It's well past dark thirty so I was driving one handed and by flashlight. But still, great to see it moving under it's own power. Not very much of a run, didn't get any air, baby steps.

I don't get excited about too many things these days, but this was a good one. The fireworks display was very appropriate.
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Picked up some wheels and tires from the track (MHOR) yesterday. The rears fit fine, they were just a used set out of the discarded tire bin just to verify they would work. There, of course, were no discarded fronts however, so I bought a set, they are not going to work, the tires are fine, but those wheels use US size bearings and my axle is metric. Didn't even consider that when I bought em, they used bearings and I just assumed... A feller should pay more attention. Going to have to order a set off the net. The slicks are kind of wild, that's what is standard down there on the clay track.

I found out their Vintage class (running this coming Saturday) is pretty much re released type rigs and any motor of your choosing (my understanding is that they primarily use brushless). Not sure if I'll be fully sorted by Saturday. I have to decided if I even want to swap everything over to modern electronics.

I don't have to actually race it, but I will take it out on that track for some laps. I at least have to run this thing is it's as close to pure stock form as possible, then I shall do some pondering on the topic. More to come...

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It's been a while since I posted, I ordered some wheels and they just came in today. They will fit fine. I'm puzzled though by what they refer to as "directional" wheels. In my head, directional means they have a left wheel and a right wheel. There are "vanes inside the wheels that will push air either in or out depending on the direction of rotation. However, these wheels I have received are all identical. No left wheel and right wheel. So the air they move will be in toward the body or out away from the body. Does this really matter? I don't think it really does. But, they are not directional. Is my understanding of term "directional wheels" wrong?
 
It's been a while since I posted, I ordered some wheels and they just came in today. They will fit fine. I'm puzzled though by what they refer to as "directional" wheels. In my head, directional means they have a left wheel and a right wheel. There are "vanes inside the wheels that will push air either in or out depending on the direction of rotation. However, these wheels I have received are all identical. No left wheel and right wheel. So the air they move will be in toward the body or out away from the body. Does this really matter? I don't think it really does. But, they are not directional. Is my understanding of term "directional wheels" wrong?

You have to run REALLY FAST to see both sides of the car at the same time! 🤣
No, you are correct. Technically, they are too though as they all go in only 1 direction. 🤣
 
Every time I see one of these retro Kyosho's it reminds of the hours and hours I spent flipping through Tower Hobbies catalogs when I was young. Nice build, looking forward to doing one someday as well.
Exact same here. I have 4 Legendary Kyoshos, and every single time I walk by them Tower Hobbies pops into my head. I still remember how I felt seeing the Javelin in the catalog for the very first time. My heart was dead set on a Turbo Scorpion, but as soon as I saw the Javelin, I ran out to my dad's woodshop to knock out another $50 worth of work to hurry up and place my order. That build, and first run has always been up there as my fondest memories right along with scoring my dream car and driving it home. It looked a helluva lot like this when I first got it, but not quite as nice. That Mustang, completely killed my interest in RC cars for a few years.
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