Kyosho Transmission ??s UPDATE: Cluster gear sol'n/Mod

[losiXXXman]

Anyone know if the RBtypeR/Evo internals can be supported by RB5/SP/SP2 stuff? Vice/versa... ? I'm assuming if the tooth counts are the same, they'd probably work...

Any and all help....much appreciated.

[lebowski770]

Yes I think it's all the same (pitch 48) however the differential gears might be designed a little differently and might not fit in one another's stealth tranny box. My ultima pro and sp2 are both pitch 48, however the sp2 can handle much higher speeds that will make the spur gear on my ultima pro pop out of place.

[losiXXXman]

You have 48p in your Ultima Pro? I wish I could find a 48p conversion for mine. I'm just trying to find a trans to put into some of my other Ultima projects that will be a little more modern, efficient, etc...I have 3stock ultimo transmissions, but only one spur cluster - and I refuse to pay $20+ for more spurs.

[lebowski770]

Yes mine is pitch 48 I have the aluminum chasis and not the Pro-XL

[Mr. ED]

You have 48p in your Ultima Pro? I wish I could find a 48p conversion for mine. I'm just trying to find a trans to put into some of my other Ultima projects that will be a little more modern, efficient, etc...I have 3stock ultimo transmissions, but only one spur cluster - and I refuse to pay $20+ for more spurs.

I've helped a friend with figuring out how to mount a B4 transmission. He was tired of seeing his gear burst while my stealth equipped ultima just kept going.
We started off with the idea of just putting in the gearbox, but eventually he put the entire spare rear-end of the b4.
I'm pretty sure we could have kept the standard suspension configuration though if he had wanted to.

[Mad Racer]

Mmmmm

You guys got me thinking But i have never had any problems with my Ultima's tranny even with a 12t brushless.

Very good info to know. Thanks

[lebowski770]

Mmmmm

You guys got me thinking But i have never had any problems with my Ultima's tranny even with a 12t brushless.

Very good info to know. Thanks

With a lipo setup aswell? Which version of the ultima do you own?

[Mr. ED]

I've personally ran my ultima with stadium truck tires for a long time without much troubles. But that was in the days that tracks didn't have that many and big jumps as today.
There are a couple things that make a big difference between different generations of ultima gearboxes.
These to me are the things to pay attention to to make it run smooth and as strong as it can be:

• bearings throug-out are a no-brainer
  the best spur cluster is the one of the ultima pro: .6 module large gear and 32 pitch backgear
  flanged bearings on the cluster to prevent rubbing the gearcover and moterplate
  correctly shimmed top axle to prevent the second gear of rubbiing with the cluster, and to prevent the inner topgear to rub with the gearcase on either side.
  hard(ened) topgear (with setscrew)
  top axle of grey colour (with the flats for the setcrew): the black one looks nicer but often is not so straight
  geardiff: though the balldiffs can be set for limited slip I never manged to stop them from slipping badly without pretty much looking them up, and even so they'd keep un-setting themselves
  runtime: a fresh all new internals gearbox requires some running in before it will get real smooth

[Mad Racer]

I have the original Ultima with turbo shock towers & gold shocks.

A Turbo with golds.

A Ultima Pro.

All i do is run the gear diff & bearings like Mr Ed said . Standard internals and Tamiya's awesome Cerea Grease. Never had a tranny fail on me in 4 yrs and i use my original ultima every weekend with a 12t brushless and Li Po's. Than again i don't do killer jumps . I still can't see any problem if you give a tap of throttle just before the landing to help with matching the wheels to the ground speed.

Cera grease helps a lot on the external cluster gears too. I'm still on my first set.

A pic with it in stock @ a vintage meet.



Sitting on pole in mod with a 12t brushless against a full grid of rc10's and JRX's. Venom Vintage festival last yr. Yes in mud. Awesome fun.

[losiXXXman]

I'm not downing the stock tranny, just the fact that the spur clusters are hard to come by. For pete's sake, there's a seller in the UK on ebay who has tons of full gear sets. But he's got them gouged @ $20 each set + $7 shipping to get them stateside. He probably bought those for $4 a piece. If I could get a handful of spurs for $20, I wouldn't be concerned with upgrading. I sourced TWO ball diffs for less than $10 watching ebay, but cannot get spurs for a fair price to save my life.

[Mad Racer]

To be honest LosiXXXman that's not too bad in price i think.

I was paying that 20yrs ago for a replacement set so for the same price 20yrs on not inc postage is pretty good.

You should see the prices of a Hard Final pinion than. As for the ball diff , they aren't the best & the gear diff is way better I feel.

Buy a new set of gears. Coat them lightly in Cera Grease . Lock tight the spur gear shaft so it won't come loose. Make a good seal for the gear cover & it will last for yrs. Well it has for me & others here.

[ProXL]

The A&L lethal weapon is still available, it has a slipper assembly and everything. I've been running a 3900kv in my PRO XL for quite some time and haven't had any issues on the stock tranny. I recommend Robinson pinions, I have a couple of Traxxas pinions and the tend to whine a bit more.

[lebowski770]

I've personally ran my ultima with stadium truck tires for a long time without much troubles. But that was in the days that tracks didn't have that many and big jumps as today.
There are a couple things that make a big difference between different generations of ultima gearboxes.
These to me are the things to pay attention to to make it run smooth and as strong as it can be:

• bearings throug-out are a no-brainer
  the best spur cluster is the one of the ultima pro: .6 module large gear and 32 pitch backgear
  flanged bearings on the cluster to prevent rubbing the gearcover and moterplate
  correctly shimmed top axle to prevent the second gear of rubbiing with the cluster, and to prevent the inner topgear to rub with the gearcase on either side.
  hard(ened) topgear (with setscrew)
  top axle of grey colour (with the flats for the setcrew): the black one looks nicer but often is not so straight
  geardiff: though the balldiffs can be set for limited slip I never manged to stop them from slipping badly without pretty much looking them up, and even so they'd keep un-setting themselves
  runtime: a fresh all new internals gearbox requires some running in before it will get real smooth

This was a full on parking lot bash with the stock wheels and stock kyosho tires, where the parking lot had a smooth shiny tar paved surface.

[lebowski770]

The A&L lethal weapon is still available, it has a slipper assembly and everything. I've been running a 3900kv in my PRO XL for quite some time and haven't had any issues on the stock tranny. I recommend Robinson pinions, I have a couple of Traxxas pinions and the tend to whine a bit more.

You bring up a good point... Also my steel pinion's hex screw is striped keeping the pinion locked on.

[fredswain]

Do any of you guys know what size the 4 small screws are that hold the original Ultima gear diff halves together?