Towers ST-15 and Ultima

[mikedealer]

vintagekyosho.com has a ultima manual, there is another foreign language site that has manuals too but i dont have a link handy at work, something like retromodelisme or something

[mrlexan]

http://www.retromodelisme.com/

[RichieRich]

Where can I find an online manual for the Turbo Ultima? or at least a part listing? I did see a manual for the Ultima a while ago but can't find it anymore.

http://www.retromodelisme.com/

Learn it. Live it. Love it.

[AYKBOBCAT]

OK thanks I got it.....

Anyone ever tried this chassis to make an Ultima hybrid?

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXWZ22&P=7

[Mr. ED]

I've been thinking of trying that but got hold of a JG carbon chassis instead. So it's off my project list for now.

It looks very similar to the ultima pro chassis, but it is better suited for stick packs than the pro chassis.

I would combine it with a topdeck to be sure. Flexibility in the chassis makes cars easier to handle/ less responsive to the terrain, but with aluminum it quickly goes beyond the point where deformations become permanent.
The korean guy making alloy parts for the optima also does the pro chassis and top deck. But if you have the black frp todeck from the turbo ultima it should work also (wheelbase is the same between pro and turbo.

(if you plan to combine the ST15 chassis with an ultima topdeck: compare the wheelbase before ordering)

[RichieRich]

OK thanks I got it.....

Anyone ever tried this chassis to make an Ultima hybrid?

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXWZ22&P=7

Hey, this might be a fun project. According to the tower website, the wheelbase is 275mm. My Ultima Pro XL wheelbase is 272mm. That's pretty close. I don't think a top deck would be needed as the chassis 2.5mm aluminum. That's pretty thick. It looks like you'll have to drill new holes to mount an Ultima transmission. The holes look correct to use an Ultima rear bulkhead. Hmmm...I kinda like this.

[Mr. ED]

The turbo ultima is 3mm thick and still bents at the nose quite easily if you run without topdeck.

[RichieRich]

The turbo ultima is 3mm thick and still bents at the nose quite easily if you run without topdeck.

Really? My Turbo Ultima's chassis is only 2mm. Are there three different versions?

[Mr. ED]

My mistake, I know there's a mm difference. can't believe the original was only a mm!

[mikedealer]

here are the differences, right is a ball diff, left is the st15. the st15 has a 32pitch i guess, and the ultima is that .5 mod or whatever metric it is.

and the internals are radically different too, nothing can be adapted, the outdrves and overall width of the diff is wider too

[Mr. ED]

Totally different indeed, thanks for posting this picture.
(glad I didn't order this)

fyi:
The pitch of the kyosho diff is 32 dp, the st15 has something larger. (The 0.5module is only a tad bigger than imperial 48dp)
There's a geardiff for the ultima also (used in cheaper cars after the turbo, and on the original ultimas before the turbo.

[Mr. ED]

one of the solutions to mount 2.2 wheels at the front is lifting everything beyond the outer hinge on the front arm and replace it with a 4wd setup from optima,mid, TC3, traxxas, HPI... whatever you can get your hands on. In the picture above I'm using cheap tamiya 4wd wheels that match the rear, but you can get different offsets and wheel widths by selecting from HB, HPI,Tamiya, MRC Academy...
The other reason I prefer having 12 mm hexes in the front is: every rim I buy can also fit my 4wd's.
You can also do a similar thing with ultima RB5 , main difference: the wheelbase get's a little shorter as the wheelaxle trails behind the steering axle. I f you go this way, flip the front arms over to extend the wheelbase. ( let me know if you need pics)


If you want to go ballbearings in the wheel: some US wheels have a center in which you can just force the 8x4mm bearings that go on a standard ultima front axle. Team CRP also sells tamiya to ultima axles on the bay, and hot trick had similar ones.
(Harder to find and HT uses a US sized nut which is pretty big and dificult to fit in the recess on the standard tamiya rims: from desert gator or desert viper)
In japan many vintage racers use the Ultima RB axles, knuckles and carrier with RB wheels. Probably not so easy to find. (RB not RB5)

For the gears, don't worry I got you covered, just bit hectic now.
This tread shows some principle pics of what will be available:
http://www.rc10talk.com/viewtopic.php?f=6&t=6874&hilit=super