Kyosho Ultima Pro: 2.2" Triumph or other wheels conversion

[HKS_TRD]

So a bit of background, I am piecing together an Ultima Pro-XL but using 6063 2.2" yellow mesh wheels on the rear
I have a pair of Triumph wheels for the front however when I pressed the bearings into the wheels and dummied them up on the font axles I see that whilst the Triumph wheels take the same bearing as the Ultima wheels, the bearings are closer together so the axle ends up being too long, the difference is about the width of a wheel
I could just use a spacer but would like to find a cleaner solution if possible
Would the axle stubs from a Triumph fit the Ultima knuckles and/or how compatible are the Triumph knuckles and hubs?
I am using the longer XL arms but wonder if using Triumph axle stubs would reduce front track, not sure how the wheel offests compare

Art there any Kyosho 2.2" wheels that are a direct fit, like say from the Pro-X? I really want yellow wheels but guess I can dye a white wheel if I have to

If any one has any other suggestions or options they have discovered please feel free to share

[RichieRich]

I think the Triumph uses the exact same knuckles and other front suspension components as the Ultima, except for the arms, obviously.

[HKS_TRD]

I'll check an online manual as I assume the part numbers would be the same.
If that's the case I could just swap the axle stubs for the shorter Triumph ones

[Mr. ED]

I think you may have to put alayer of cellophane tape araound the axle before putting it in the knuckle. I think they are a tad smaller diameter and have play hen used with the ultima knuckles. Could have been part tolerances though.
The pro-xl used C-carriers with 2 lower holes by the way; allowed you to slim or widen the front depending on the tire size

[HKS_TRD]

Looks like the Triumph C Hubs and knuckles have different part numbers so won't work but using the Triumph axle stubs and the altenate hole to make the front wider should work

Are there any other 2.2 inch wheels that fit the front of an Ultima?

[Mr. ED]

It should work as i explained, but if you prefer another route: team crp sells axles to mount 'tamiya' wheels; typically using 5x11bearings: such as the sand viper ones. Some older traxxas wheels also have 5mm bearings and work with that axle too. Team crp also has these same axles with an extra 5mm width to widen the front of the ultima.
Alternatively you can press 8x4mm bearings in a certain size imperial wheels for the rc10, but I don't have any of those and don't know if they are 2.2"
The sand viper wheels are a dark metalic grey and now also available in black.

The rear sand viper wheels work on the ultima pro also, so you have nice matched set. But they do narrow the rear a bit as they have less offfset than the original one. Then again: the same is true if you use triumph or lazer wheels in the back.

The desert gator white front and rear wheels are an alternative to the sand viper ones but they scream Tamiya

[Mr. ED]

PS: you could also adapt the axle to the triumph wheels: Just extend the tread part and cut the part that's too long: if you have acces to treading tools.
The triumph wheels became somewhat easier to find again as hype/chadori used them on their cars

[HKS_TRD]

I think I will go with the Triumph stub axles, hopefully the wheels won't foul on the rod ends because comparing the two wheels the triumph wheel does have a different offset and makes the front narrower

Are you sure about the rear wheels being different offset, I know the ZX-5 wheels are but the older ZX-R wheels are the same rear offset as a mid, its just the front thats different, you can tell when looking at a ZX-R that the rear wheels have a bit more dish on the face than the front ones.

I'm going to put CVDs on this build so I can always use the ones with the longer axle and run a flanged bearing on the rear hub to give me a bit of extra width

So far I have built the ball diff for this project so thats a start!

The theme of the build is Ultima Pro XL-R i.e. sort of what Kyosho would have done next with the original Ultima series if they didn't go to the Triumph and the UlitmaII cars. I am trying to keep it all Kyosho parts, I have the Option House Carbon Chassis which I understand is pretty rare, and Fibrelyte made all the other bits in carbon for me including a shock tower that is taller so it will work with Medium length shocks and I have had a bunch of pieces anodised in gunmetal grey

I have a genuine body and decal set for it and it will just be box art because I love the black XL box art though I will use the UMW-1 wing mount instead of the wire wing mount

Damn I just gave the whole project away!

[Mr. ED]

I'm not all that good with the differet generations of lazers. But I know the ZX5 (before SP1) optional yellow wheels are the same design as earlier lazers. Only the colour is a bit different: more fluo on the newer wheels. That's the full dish design.

Probably too late, but I always thought kyosho should have made a narrower bulkhead for the pro-xl : matching the rear inner hinge location rather than basically copying the andy's dimensions for the front arms.
I think what you plan is a little along the lines of PRP's replica of Joel johnson's 89WC car (NOT the 87 champion car)
http://www.rc10talk.com/viewtopic.php?f=77&t=30992

[HKS_TRD]

Wow that guy sure has one amazing collection!
I have the same Trinity chassis as the Joel Johnson Mid, maybe I will try to build something similar down the track

Another possibility for the front end is to just make spacers to sit between the inside knuckle and the bearing, something plastic that will be a nice interference fit on the shaft but easily removed if need be

I have a pair of Andys front wishbones (the black ones not the white ones) here that I have misplaced, are they as long as the XL front arms?

[Mr. ED]

yep, the andy's are the same length as the pro-xl arms.
Something which doesn't work and I learned this the hard way: putting flanged bearings in the triumph wheels.
Doing that leaves a small gap between the inner rib of the wheel and bearing surfaces. After a couple runs you'll find the bearings broken in the wheels.
(Same problem with the yokomo wheel adapters for the ultima front ... only suited for shelf queens )

[HKS_TRD]

I have a pair of Triumph axles on the way along with pieces for two of my other projects
Thanks for the tip on the bearings

I did some searching on this forum and found mention of an RB5 front end conversion but not the actual details, is there a thread this is covered in?

[Mr. ED]

http://www.rc10talk.com/viewtopic.php?f=30&t=6543&p=86678&hilit=+ultima+rb5+hex#p86678

I did this also but didn't like it so much.
The trailing axle shortens the wheelbase even more.

[HKS_TRD]

So I found this thread listing the bits required for the conversion

http://www.rc10talk.com/viewtopic.php?f=30&t=15755

And I discovered you can get yellow RB5 front wheels to match the mesh wheels I have for the back so I think I will do the RB5 conversion either on this car or another runner

Does it shorten the wheelbase much? I'm using a LWB chassis anyway but no one else seems to have made the observation or complained about

Now I'm wondering if I should put a Triumph or A&L Tranny on this but I already have the motor plate anodised and a carbon motor brace made up for it along with the internal slipper clutch and hard final pinion

[RichieRich]

Oh yeah, that's a good thread.