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

[Littlemotor]

Hey wow man! Those Race Prep Gold connectors take me back to the late 80’s when I was using them! Haven’t seen Andy’s “Wide Track” arms in YEARS either!! Awesome build!

 

[RudyF6]

I like your Bronco, and the Bronco sitting on it. I've owned 3 of em ( full size) over the years. Great rigs.

Thanks! I've had 8 over the years!

 

[WickedFog]

Looks like I'm missing a piece (I'm sure it won't be the last) they call the "Motor Guard Collar". Pretty specialized. Might be able to replace it with a stack of washers.

View attachment 235535
View attachment 235537

Kyosho revamped the wing stay on the re-release of the Ultima. Those standoffs are now molded onto the wing stays. You should be able to use these, but may require use of the re-released wing on this, unless you are trying to stay original with it. Anyway, here is the stays.
https://www.rcmart.com/kyosho-ultima-wing-stay-ut003-00086459

Kyosho part number UT003

Here is the re-release manual for reference.
https://images.amainhobbies.com/ima... Ultima Off Road Racer 2WD Buggy - Manual.pdf

 

[WutUp Clegg]

They have followed me around for 36 years, I believe I'll hang on to them. Do they have any collector value?

I recall having to solder those capacitors/diodes/ whatever they are on to them. I guess for radio interference reasons.

I'm certainly no expert, back in the day we messed around with differing spring rates and stepped brushes. There was no internet in those days, most of what I learned was from the magazines and local hobby shops.

I'm still a fan of brushed motors and hopefully they will spin the tires on this rebuild.

Jeff

You should hold onto them. The old school ones are collector items. They are not nearly as fast as the new stuff, including the brushed motors, but they are still desired to install in a shelf queen car.

 

[JRFisher]

An exploded view of the front end.

The long rod on the right A arm is bent. I persuaded it back to relative straightness as best as my eyecrometer can tell. I'm glad I took them all the way down. Clearly this side took a good hit as this is the side that the shock tower is also broken.

I had bought a new shock tower back then but never put it in. Now looking at it, it is slightly different that the original. The main two mounting holes are the same, everything else is slightly off. Not sure if this was by design or If I got the wrong one. I'm sure it's close enough that some adjustments of the linkages will make it right. After all, I won't be competing in any nationals with this...

Closing in on reassembly and smoke testing.

 

[CertifiedMike]

Closing in on reassembly and smoke testing.

Good luck!!!

 

[JRFisher]

I think I'll reassemble as fully as I can (even with a few broken parts) so I can fully identify anything missing. I have a bunch of stuff on order and it will take a while for it all to show up. Some is coming in on the slow boat. After everything comes in, will replace broken with new.

When I was putting the front end together I discovered the front bulkhead was in bad shape. There was a lot of busted stuff on this front end, clearly it was abused by someone!

I've noted that I had removed the front and rear stabilizers at some point. I don't know if I thought they were not needed or what. Today's brain thinks I should use them so I will.

I didn't think I would need to spend too much on this, but I'm up to about $300 so far.

List of things I bought:
Ball diff unit, ($100 by itself)
Front and rear stabilizers with essentials,
A full screw and bolt set,
Front bulkhead (comes with rear bulkhead and misc parts),
Full bearing set,
Set of wheels,
E clips,
Shock springs,
Front A arm rods.
I may have forgotten a couple things.

I've found it tough to find things specific to the Ultima Pro, it's like the forgotten ultima. Amain has some stuff, rc Mart has some, a little on the evil bay.

And I would like to say again, I hate Philips head screws, i always have, they should be outlawed. They have no redeeming qualities.

 

[CertifiedMike]

Ah, dug deep for the new diff... I haven't got the new diff rings yet.

I found plazajapan.com was great for pricing and carries parts that I couldn't find in US.
Liquidrc.com has great pricing and stock but the site is a bit pita to navigate on a mobile.

Factoryworks.com has a lot of vintage hop up and chassis parts. You couod get your shock mount there too I'd bet.

My bearings and a set of turnbuckles came from avidrc.com price was great on hybrid breaings that really do seem to roll smoother and def faster that my stockers.

I have been replacing phillips with 12.9 hardware from monsterbolts.com They have been amazing. Everything has been in stock, shipped fast with great pricing.
I think Exotek had 12.9 in gold if you wanted something fancy too.

JCRacing makes nice Kyosho wheels if you are looking for another source. Kyosho JUST started making a set of CORRECT offset 2.2" wheels for the optima mid.
I think they are the same as the rears on your Ultima.

Marwan.com makes tires bodies, decals.

Teambluegroove.com has an AWESOME selection of lexan too. They are great to deal with!

I got hardened hinge pins from koswork.com His design eliminates the eclips!
Those were for the Optima Mid. He might have stuff for the Ultima also.

Those you have A arms are Andy's A arms and were/are great!

I've been working on these cars for a while now. I've finally got a decent list of suppliers

 

[JRFisher]

Ah, dug deep for the new diff... I haven't got the new diff rings yet.

I found plazajapan.com was great for pricing and carries parts that I couldn't find in US.
Liquidrc.com has great pricing and stock but the site is a bit pita to navigate on a mobile.

Factoryworks.com has a lot of vintage hop up and chassis parts. You couod get your shock mount there too I'd bet.

My bearings and a set of turnbuckles came from avidrc.com price was great on hybrid breaings that really do seem to roll smoother and def faster that my stockers.

I have been replacing phillips with 12.9 hardware from monsterbolts.com They have been amazing. Everything has been in stock, shipped fast with great pricing.
I think Exotek had 12.9 in gold if you wanted something fancy too.

JCRacing makes nice Kyosho wheels if you are looking for another source. Kyosho JUST started making a set of CORRECT offset 2.2" wheels for the optima mid.
I think they are the same as the rears on your Ultima.

Marwan.com makes tires bodies, decals.

Teambluegroove.com has an AWESOME selection of lexan too. They are great to deal with!

I got hardened hinge pins from koswork.com His design eliminates the eclips!
Those were for the Optima Mid. He might have stuff for the Ultima also.

Those you have A arms are Andy's A arms and were/are great!

I've been working on these cars for a while now. I've finally got a decent list of suppliers

Sweet, thanks for the great resources!

I'll be busy looking stuff up today!

Started poking around with the shocks, I'm missing the seals and clips apparently. I do have a parts bin to dig through again but I let things get commingled so it will be a search. Perhaps I'll find a rebuild kit on one of those site recommendations.

Thanks again.

 

[JRFisher]

Ah, dug deep for the new diff... I haven't got the new diff rings yet.

I found plazajapan.com was great for pricing and carries parts that I couldn't find in US.
Liquidrc.com has great pricing and stock but the site is a bit pita to navigate on a mobile.

Factoryworks.com has a lot of vintage hop up and chassis parts. You couod get your shock mount there too I'd bet.

My bearings and a set of turnbuckles came from avidrc.com price was great on hybrid breaings that really do seem to roll smoother and def faster that my stockers.

I have been replacing phillips with 12.9 hardware from monsterbolts.com They have been amazing. Everything has been in stock, shipped fast with great pricing.
I think Exotek had 12.9 in gold if you wanted something fancy too.

JCRacing makes nice Kyosho wheels if you are looking for another source. Kyosho JUST started making a set of CORRECT offset 2.2" wheels for the optima mid.
I think they are the same as the rears on your Ultima.

Marwan.com makes tires bodies, decals.

Teambluegroove.com has an AWESOME selection of lexan too. They are great to deal with!

I got hardened hinge pins from koswork.com His design eliminates the eclips!
Those were for the Optima Mid. He might have stuff for the Ultima also.

Those you have A arms are Andy's A arms and were/are great!

I've been working on these cars for a while now. I've finally got a decent list of suppliers

Spent a good part of my day looking through these links and what they have to offer, great batch of resources here, thanks again.

BTW, marwan address is marwanrc.com.

 

[CertifiedMike]

Are you missing the bladder seals or orings?
You can buy the shock collars in red or black for your gold shocks. OT210RB/B
Orings are the P3 size (3mm)
Thats avail right from Kyosho.

Bladders are a different story and are pretty $$$ if you try to buy a set of legit Kyosho.

https://www.racing-cars.com/1-10th-touring/mi6evo/small-bore-diaphragm-pk4-u4362

I think these will work but have not tried them yet.

Schumacher 7172 rebuild kit looks promising but I haven't ordered one to try yet.

Those sites are pretty great! Lots of candy to drool over for a vintage Kyosho lover!!!

 

[JRFisher]

It was a shocking day today!

I have 2 front shocks and 4 rear shocks, not sure how I ended up with that. The two cleaner rear shocks didn't have the rubber o ring seals or plastic o ring bits, however the crusty ones did have it all and they look to be in ok shape. I may still just buy some new. The rubber end caps on the front shocks were sitting in oil for 36 years and look to be a little dissolved. The other 4 though look to be in relatively good shape. Again, if I can find suitable replacements I will like replace them anyway, I mean, 36 year old rubber!

You can see in the picture the variable rate internals I was using. I had some in the front shocks and some in the rusty shocks. The theory seems sound, I'm guessing it didn't really make that much difference as I see nothing like this available today.

I'll certainly need a new set of springs. I'm missing two of those spring holders that go on the bottom of the shocks. They look pretty standard so I may have some Axial ones sitting in my parts bin. Also missing 2 of the little circlips for holding in the shock o rings.

 

[CertifiedMike]

Yeah, all those plastic parts are availible right from Kyosho for the shocks.
Look for the Ultima medium hardness spring set or if you can find them, otw123, 124 springs also from Kyosho.
The circlip things, I'd replace with snap rings I think.
Those variable rate pistons look pretty cool! MIP made tunable pistons for a long time. Maybe those were a prototype.

Looks like those poor shocks were just about due for rebuilding!

You're ripping right thru this resto!

 

[JRFisher]

Well, I was sitting here pondering (I do that a lot) and I noticed this weirdly bent little bar that had been sitting around from the Ultima's parts I have. I realized it was for the steering. The turnbuckle with ball ends was what was there when I took it apart. I guess at some point I put that in thinking it was an improvement. Fiddling with it this original would be smoother than the ball ends. Less friction for sure. I think I'll stick with the original. The plain metal bent rod doesn't register on my scale, the turnbuckle one weight 2 grams. Who cares really, but it just seems more correct. The little things that amuse me...

 

[JRFisher]

Got a couple things in the mail today, the ball diff assemble and the bearings. So I started putting the rear gear box together. I'm replacing as many of the phillips head screws with hex heads as I can. (Did I mention how much I had phillips head screws?)

This is where all those little missing components start to rear their heads. I wish they would raise their heads so I could find them. I'm searching my many containers of misc parts to try to find what I need. You would think an M3x45 would be there somewhere but no luck so far, its a fairly long screw. That motor guard collar has not shown, I'm just going to stack a couple thing together, since there are three total screws holding this motor guard plate on I think the middle one will be fine with whatever I stack together. I had disassembled this rear gear box 36 years ago, not everything stuck around.

Then there is that center gear assembly. I'm missing the center gear collar and not sure what the thickness should be, I have replaced it with another one of those 4x8 bearings (seems pretty close) and a few shims and I think I have the thickness pretty dang close. Part of the guessing game is the dimensions of the M4 washers. The net says an m4 washer is 4x12x.5 but I think it should be 4x10, I found a couple that are that size and used em. That entire stack looks right and spins smooth. The O ring on the end I used an old shock O ring that fits nicely. It's the battle of the missing little parts going on here. I'm muddling through. Now to find a couple of 2.6x6mm screws, what an odd size. Why not just use their standard 3mm? (After I wrote this I found some 2.5 size screws, they seem to fit fine, I just won't overtighten them and use plenty of lock tight. What's .1mm amongst friends?) I just needed to turn away for a bit so I wrote an update. Back in the day I might not have handled my frustrations so easily, today I'm doing ok with it. When I get stuff in I want to get some progress, when I hit a roadblock I just find something else to do for a bit.

3 or 4 more deliveries supposed to be here before too long. One is the front bulkhead which comes on a tree and includes the rear bulkhead and a few other misc parts. I'll replace them both, why not? I'm sure thankful I still had this manual, It's a critical resource in this rebuild.

 

[CertifiedMike]

Got a couple things in the mail today, the ball diff assemble and the bearings. So I started putting the rear gear box together. I'm replacing as many of the phillips head screws with hex heads as I can. (Did I mention how much I had phillips head screws?)

View attachment 236117


This is where all those little missing components start to rear their heads. I wish they would raise their heads so I could find them. I'm searching my many containers of misc parts to try to find what I need. You would think an M3x45 would be there somewhere but no luck so far, its a fairly long screw. That motor guard collar has not shown, I'm just going to stack a couple thing together, since there are three total screws holding this motor guard plate on I think the middle one will be fine with whatever I stack together. I had disassembled this rear gear box 36 years ago, not everything stuck around.

Then there is that center gear assembly. I'm missing the center gear collar and not sure what the thickness should be, I have replaced it with another one of those 4x8 bearings (seems pretty close) and a few shims and I think I have the thickness pretty dang close. Part of the guessing game is the dimensions of the M4 washers. The net says an m4 washer is 4x12x.5 but I think it should be 4x10, I found a couple that are that size and used em. That entire stack looks right and spins smooth. The O ring on the end I used an old shock O ring that fits nicely. It's the battle of the missing little parts going on here. I'm muddling through. Now to find a couple of 2.6x6mm screws, what an odd size. Why not just use their standard 3mm? (After I wrote this I found some 2.5 size screws, they seem to fit fine, I just won't overtighten them and use plenty of lock tight. What's .1mm amongst friends?) I just needed to turn away for a bit so I wrote an update. Back in the day I might not have handled my frustrations so easily, today I'm doing ok with it. When I get stuff in I want to get some progress, when I hit a roadblock I just find something else to do for a bit.

3 or 4 more deliveries supposed to be here before too long. One is the front bulkhead which comes on a tree and includes the rear bulkhead and a few other misc parts. I'll replace them both, why not? I'm sure thankful I still had this manual, It's a critical resource in this rebuild.

View attachment 236118

When I started bouncing between vintage and rerelease parts, I found out that changes were made...
I needed part #'s and exploded views that my old manuals didn't have.

https://www.rcscrapyard.net/kyosho.htm

This place has a crazy amount of lit availible when you need more info.

 

[JRFisher]

When I started bouncing between vintage and rerelease parts, I found out that changes were made...
I needed part #'s and exploded views that my ood manuals didn't have.

https://www.rcscrapyard.net/kyosho.htm

This place has a crazy amount of lit availible when you need more info.

That's a great link, thanks...

 

[JRFisher]

As I await a few more packages to arrive (I hates waiting), I was taking a look at my turnbuckles and ball ends. They are all very tight, I took them apart and cleaned but still quite tight. I imagine the plastic shrinks over time. I considered buying some new links but my primary objective is to get some nice smooth ball ends in place.

A learning point I discovered was the collar on the turnbuckle indicates which side is reverse thread. Learn something new every day.

Amain has some nice looking Yeah Racing aluminum Rod Ends but I think the threaded portion is a bit short, especially for my front which is wider than stock. Not even sure if they are "the best" to use or not. They look spiffy. CertifiedMike mentioned the titanium turnbuckles but I would have to do some accurate measuring to make sure I get the correct length.

My big question is, what are the best ball ends to use? I am interested in making the suspension and steering as smooth as I can.

 

[CertifiedMike]

I used 5.8mm balls because thats Kyosho stock on the Optima Mid. LA43H rod ends made a huge difference in smoothness for me.
W201H hardened 5.8mm ball were the other half of the magic.
The 'H' indicates harder materials.
I also switched to titanium ball studs in a few spots, mostly just to save weight tho.

I have never had good luck with those metal rod ends like the ones from Yeah Racing.
Those might be better for crawling.
Its been a while since I've been to the track but no one was running that style end.

I believe the Ultima uses a combination of 4.8mm and 5.8mm balls and cups in the later versions but I THINK yours are mostly 5.8mm

There are hardened versions of all the 4.8mm parts too in case thats the size you need.

Check the links on rcscrapyard for Ultima optional parts lists.
I found optional parts info for the Optima Mid there. It made finding the correct length rods and identifying a few other parts very easy.

Your Andy's arms may be wider than stock.
Andy's arms for Mid are same length.

I replaced my threaded rod with titanium because it was lighter and for ease of adjustment. My car had NO turnbucles.

If you like the turnbuckle you have, if they aren't bent, theres nothing wrong with keeping yours to reuse.

My old cars used dog bones instead of CVAs... HUGE difference there too if you're after 'smooth'. There is NO binding!
They are also lighter so less rotating mass was an easy sell for me!

Avidrc.com hybrid bearings might require more maintenance over time but they are 1000% smoother, they glide vs a standard steel bearing.
I did not think there could be such a difference in bearings.
I was wrong.
It you want smooth, for the price, I think you'll be blown away!!! I don't think you can buy more 'smooth' unless maybe with full ceramic bearings.

I would remove the control arm hinge pins and polish them with Mother's Aluminum and Mag wheel polish before reassembly, use shims to remove front to rear 'play' movement from the arms.
Shimming made a massive difference. Made the car go from feeling worn out and flimsy to tight and tough.

If your old buggy is worn out like mine was, these changes should make your car feel like a completely different RC.

I used a bit of parafin wax on the threaded rod threads as well as in the ball ends as a bit of 'dry lube'.
It seems to be helpful too.

Hopefully that will keep you busy while you wait for your next delivery.

 

[CertifiedMike]

https://www.ebay.com/itm/3882259381...CfjDAex4CR20MzIyv3z8+d7bY=|tkp:Bk9SR9KmjpDkZQ


Didn't you say you needed these?