Puzzled

[violetmind]

Thought I pulled out an Ultima rear gear box from my storage box but was surprised to see the pinion gear and plate on the left instead of the right. Does anyone know what buggy does this belong to?

Thanks

[DCLXVI]

Are you sure it's not just assembled wrong? On the pics, theres a hint of a circle from the motor and on the other side it looks like a line that would be from the gear cover, I might be mistaken though...

[tsan_derson]

Are you sure it's not just assembled wrong?

Good eye. I think that's the case. Here's some pics I took for my blog during a tear down of my Turbo Optima. Notice the access hole on top of the gear box... on my gear box, the flat part of the hole is on the motor mount side. On your gearbox, the flat pat is away from the mount. Unless another car used this gearbox in a mid motor configuration(?), I think it's an Optima gearbox.

Good find either way.

(CLICKY)

[violetmind]

Are you sure it's not just assembled wrong? On the pics, theres a hint of a circle from the motor and on the other side it looks like a line that would be from the gear cover, I might be mistaken though...

I thought so too at first. But I looked closer at the way the metal was assembled or attached to the plastic gearbox and it seemed too nice a fit to be assembled wrongly. Check out this pic (see the parts that links/joins the black plastic gearbox to the metal motor plate).

[tsan_derson]

I thought so too at first. But I looked closer at the way the metal was assembled or attached to the plastic gearbox and it seemed too nice a fit to be assembled wrongly. Check out this pic (see the parts that links/joins the black plastic gearbox to the metal motor plate).

I tried to edit my post before you posted about that... i just noticed that too. You`re way too fast!

I am very curious now!

[tsan_derson]

I've posted pics of the gearbox on rc10talk, and this is what I've gotten so far:

Q

A few of us on another forum have been trying to id this kyosho gearbox. I thought the answer might be found here.

One theory is it's an incorrectly assembled Ultima gearbox...

Any ideas?

A1

I'm guessing incorrectly assembled. Although I'm only using an Optima gearbox as comparison (and going from memory), it looks like some screws would not be going into the proper screw-holes. It looks like the large motor side-plate is on the wrong side. I'd venture that the gearbox should be bolted onto the other side of that side-plate. Don't quote me on that, though.

A2

it looks to me like someone tried to assemble the gearbox in a mirror fashion, either to run it in a 'front drive' scenario, or with a mid motor configuration.

the motor plate looks reversible, and those standoffs look like they might be hand made.

[RichieRich]

I'm pretty sure that's just a standard Ultima gearbox that's been assembled in a mirror image fashion. The 2 aluminum standoffs, plate and box bar belong to the motor guard's parts.

[Scottgir]

Thought I pulled out an Ultima rear gear box from my storage box but was surprised to see the pinion gear and plate on the left instead of the right. Does anyone know what buggy does this belong to?

Thanks

It looks like the ultima gen 1 gear box but assembled wrong. The aluminum plates are reversible so who ever put it together could've put it on the wrong side.

I don't remember there being any mid motor conversion for the ultima but could've been.

[violetmind]

Thanks guys for all the effort and replies.

Almost there but still not 100% convinced this was assembled wrongly. I understand the points raised about mirror-like assembly and the aluminium standoffs (which I assume is the metal part between the plate and the gearbox through which the screw goes) being part of the plate. But if that is the case, then the black plastic gearbox must have been so expertly cut such that the aluminium standoffs fit so snug and flawlessly (see 3rd pic I provided).

Don't wish to over do it but I'll keep the request for help open for a while longer. I'm no expert in Kyoshos so all your advice has helped. If nobody comes by with another idea/solution/answer, I'll take it that this was assembled the wrong way around.

Thanks again!

[RichieRich]

If it'll make you feel any better, I will assemble a similar gearbox with my parts. Note that this configuration does not make sense as it leaves huge gaps where dirt and small pebbles can get into the transmission. There is no way to cover these holes with any stock Kyosho parts. At least, I've never seen any.

[Champ85]

It is assembled backwards.

The metal standoffs denoted by the yellow boxes in this picture are in the correct position.

You are correct in thinking they were designed to fit into the plastic gearbox.

The motor guard brace and motor mounting plate denoted by the yellow arrows are on the wrong sides.

They need to be switched, leaving the metal standoffs shown in picture 1 where they are.

At the same time, the gear denoted by the green box must also switch sides so it moves with the

motor mounting plate.

After switching the motor plate to this side, you'll find that the hole in the plate snugly fits the round hole

denoted by the yellow box in this picture. The gear will also fit nicely inside the round hole, too.

Also, someone has filed away material in the location denoted by the green box. Usually there is a

small plastic "plug" that snaps into place to prevent dirt from entering the gearbox.

Edit: The top gear inside the gearbox plus its shaft will also have to be flipped around in order to

follow the final gear switch on the outside.

Due to the effort of filing out the top of the gearbox, I would say this backwards assembly was done on

purpose rather than by accident. They filed the gearbox in order to gain access to the top gear inside for

either grease/oil or because the top gear rubbed the gearbox there when installed backwards like that.

The tolerances inside the gearbox were very close and if I remember correctly, the top of the gearbox

halves (or maybe just one of them) has a cutout for the top gear so it doesn't rub the gearcase.

The good thing is replacement UM-3 gearboxes are cheap (like $5 US plus shipping), so

if you want to seal up the top like new you have that option. Even cheaper, just use black electrical tape.

[violetmind]

A big thanks to everyone for the strong support and help!

[DCLXVI]

Or you could build a mid-motor Ultima...