Go Back  R/C Tech Forums > General Forums > Electric Off-Road
Kyosho Ultima RB6 & RB6.6 Car Thread > Kyosho Ultima RB6 & RB6.6 Car Thread
Like Tree39Likes

Kyosho Ultima RB6 & RB6.6 Car Thread

    Hide Wikipost
Old 12-21-2016, 08:46 AM   -   Wikipost
R/C Tech Forums Thread Wiki: Kyosho Ultima RB6 & RB6.6 Car Thread
Please read: This is a community-maintained wiki post containing the most important information from this thread. You may edit the Wiki once you have been a member for 90 days and have made 90 posts.
 
Last edit by: tobamiester
RB6.6 Kyosho America Product Page: http://www.kyoshoamerica.com/ULTIMA-...T_p_24505.html

RB6.6 Manual http://www.kyosho.com/jpn/support/in...A_RB6_6_IM.pdf

RB6.6 Kyosho Youtube https://www.youtube.com/watch?v=vW_sR667utY

MSRP $639 MAP $399.99

-------------------------------
New RB6.6 parts (compared exploded views, prices and links are Kyosho America):

Chassis:
  1. Main chassis - UM731 - $125.99
  2. Side guards - UM732 - $9.99

Battery Holder:
  1. Battery plate - UM733 - $8.99
  2. Battery foam - UM741 - $7.99

Rear Bulkheads:
  1. MM3 and Laydown - UM740 - $9.99
    • MM3 bulkhead
    • Laydown bulkhead
    • Swaybar Holders

3 Gear Transmission (MM and RM):
  1. Transmission - UM734 - $10.99
    • transmission cases
    • spacers
    • caps
    • plastic FR & RR suspension hangers

  2. Gear Cover - UM735 - $6.99

Laydown Transmission (3 and 4 gear possible):
  1. Transmission - UM736 - $10.99
    • transmission cases
    • spacers
    • caps
    • required extra hardware
    • pastic FR suspension hanger

  2. 40T idler - UM737 - $6.99
  3. Motor plate - UM738 - $18.99
  4. Gear cover - UM739 - $6.99

Body:
  1. Blade body - UMB05 - $27.99

Optional Parts:
  1. Lightweigt Blade body - UMB05LW - $31.99
  2. Aluminum FR suspension hanger - UMW705B - $28.99 (may be able to file UMW705 to fit)
  3. Brass FR suspension hanger - UMW725B - $30.99 (looks more different than UMW725..someone confirm?)

Typical Upgrades for new RB6.6 Buyers

UMW701 Aluminum Steering Plate (RB6)
UMW702 Aluminum Crank Arm (RB6)
UMW704-0 V2 Aluminum Rear Hub Set(0/RB6)
UMW705B Aluminum Rear Sus. Holder (RF/RB6.6) or brass UMW725B
UMW707 Aluminum Rear Sus. Holder (RR-Mid)

Nice to have:

UMW723 Aluminum Front Sus Block (Type B/10g/RB6/RT6/SC6).


Aftermarket Parts:

Front Wing: https://www.prolineracing.com/perfor...mount-alum-rb6

Print Wikipost


Old 10-09-2013, 06:28 AM
  #8386  
Tech Elite
iTrader: (1)
 
Join Date: Sep 2007
Location: All 48 states...
Posts: 2,053
Trader Rating: 1 (100%+)
Default

Originally Posted by function>form View Post
What is the advantage of the 521 rear arms?
Gives a slightly looser feel to rotate and squares up faster than stock arms.
Gitsum is offline  
Reply With Quote
Old 10-09-2013, 07:21 AM
  #8387  
Tech Master
iTrader: (2)
 
Razathorn's Avatar
 
Join Date: May 2009
Posts: 1,972
Trader Rating: 2 (100%+)
Default

Originally Posted by function>form View Post
What is the advantage of the 521 rear arms?
The kit arms are "gull winged", which puts the shock lower than the 521 flat arms. The effect is that the progression of damping and spring is different between the two arms. The gull winged kit arms take longer to "stiffen up" during compression, where as the flat arms do not. The effect is that damping and spring is far softer initially on the kit arms, which is similar to running your shocks way further in, or a much lower rear roll center.

Tebo told me that with the kit arms you really need to run a thicker oil in the rear compared to the flat arms. He didn't tell me any of the stuff I wrote above -- that is MY take on what is happening.

The bottom line is the 521 arms roll less, and the classic outcome of that is the car squares up better out of corners and rotates a little more. It's like raising the rear roll center significantly more than you can with ball stud washers. It puts the rear end in an entirely different roll profile. On most surfaces, even loose ones, it is better IMHO.
Razathorn is offline  
Reply With Quote
Old 10-09-2013, 08:03 AM
  #8388  
Tech Master
iTrader: (56)
 
Join Date: Feb 2010
Location: Valley Cottage NY
Posts: 1,888
Trader Rating: 56 (100%+)
Default

Originally Posted by Razathorn View Post
The kit arms are "gull winged", which puts the shock lower than the 521 flat arms. The effect is that the progression of damping and spring is different between the two arms. The gull winged kit arms take longer to "stiffen up" during compression, where as the flat arms do not. The effect is that damping and spring is far softer initially on the kit arms, which is similar to running your shocks way further in, or a much lower rear roll center.

Tebo told me that with the kit arms you really need to run a thicker oil in the rear compared to the flat arms. He didn't tell me any of the stuff I wrote above -- that is MY take on what is happening.

The bottom line is the 521 arms roll less, and the classic outcome of that is the car squares up better out of corners and rotates a little more. It's like raising the rear roll center significantly more than you can with ball stud washers. It puts the rear end in an entirely different roll profile. On most surfaces, even loose ones, it is better IMHO.
when your talking about the 521 arms, u mean 521-1 not reg 521 right?
Speedychris22 is offline  
Reply With Quote
Old 10-09-2013, 08:11 AM
  #8389  
Tech Champion
iTrader: (73)
 
MikeXray's Avatar
 
Join Date: Oct 2006
Location: New York
Posts: 5,753
Trader Rating: 73 (100%+)
Default

Originally Posted by Speedychris22 View Post
when your talking about the 521 arms, u mean 521-1 not reg 521 right?
The only difference between them is the shock hole, the 521 has inside/outside, and the 521-1 is the middle of those two.

My car was really good in 17.5 with the rb6 arms/MM but could be a bit more free, going to swap arms this week and see if I can feel or see it in the lap times.
MikeXray is offline  
Reply With Quote
Old 10-09-2013, 08:46 AM
  #8390  
Tech Master
iTrader: (19)
 
hobdog's Avatar
 
Join Date: Jul 2008
Location: Albany, OR.
Posts: 1,035
Trader Rating: 19 (100%+)
Default

So just to clarify, When putting a .5 shim under the rear toe block on mid motor configuration like Tebo did on the worlds set up, I would also have to add a .5 shim under the tower to make it correct.
hobdog is offline  
Reply With Quote
Old 10-09-2013, 09:33 AM
  #8391  
Tech Master
iTrader: (44)
 
function>form's Avatar
 
Join Date: Nov 2008
Location: hanover pa
Posts: 1,010
Trader Rating: 44 (100%+)
Default

Originally Posted by Razathorn View Post
The kit arms are "gull winged", which puts the shock lower than the 521 flat arms. The effect is that the progression of damping and spring is different between the two arms. The gull winged kit arms take longer to "stiffen up" during compression, where as the flat arms do not. The effect is that damping and spring is far softer initially on the kit arms, which is similar to running your shocks way further in, or a much lower rear roll center.

Tebo told me that with the kit arms you really need to run a thicker oil in the rear compared to the flat arms. He didn't tell me any of the stuff I wrote above -- that is MY take on what is happenin
The bottom line is the 521 arms roll less, and the classic outcome of that is the car squares up better out of corners and rotates a little more. It's like raising the rear roll center significantly more than you can with ball stud
washers. It puts the rear end in an entirely different roll profile. On most surfaces, even loose ones, it is better IMHO.

Thanks for the explanation.

Last edited by function>form; 11-25-2013 at 06:18 PM.
function>form is offline  
Reply With Quote
Old 10-09-2013, 12:38 PM
  #8392  
Tech Master
iTrader: (21)
 
carbons2k's Avatar
 
Join Date: May 2011
Location: Long Island, NY
Posts: 1,801
Trader Rating: 21 (92%+)
Default

Originally Posted by MikeXray View Post
The only difference between them is the shock hole, the 521 has inside/outside, and the 521-1 is the middle of those two.

My car was really good in 17.5 with the rb6 arms/MM but could be a bit more free, going to swap arms this week and see if I can feel or see it in the lap times.
Mike, try 0 degree hubs
carbons2k is offline  
Reply With Quote
Old 10-09-2013, 03:57 PM
  #8393  
Tech Initiate
iTrader: (1)
 
Join Date: Jun 2013
Location: Shorewood, MN
Posts: 22
Trader Rating: 1 (100%+)
Default

Originally Posted by hobdog View Post
So just to clarify, When putting a .5 shim under the rear toe block on mid motor configuration like Tebo did on the worlds set up, I would also have to add a .5 shim under the tower to make it correct.
This is true, as far as I understand it. I believe if you eliminate this shim, you instead use the 1.0 shim under the tower.
kes7u is offline  
Reply With Quote
Old 10-09-2013, 04:10 PM
  #8394  
Tech Master
iTrader: (66)
 
cnelson3's Avatar
 
Join Date: Nov 2010
Location: Milwaukee, WI
Posts: 1,213
Trader Rating: 66 (100%+)
Default

Originally Posted by Jonny5 View Post
Well now I'm glad I posted pics. I looked at pics of Tebo's car from CRCRC and really couldn't see it clearly. Guess I should have checked his Reedy Race setup as it clearly showed the arms the opposite of how I mounted them. First Kyosho build. Looks like I have a little more to do tomorrow.

By the way, your buggy looked really good on Friday. I was shocked to see how well the MM cars are running up there. We'll see you up there soon!



Thanks for the attempted bail out buddy.
Thanks. I recently went back to rear motor for testing purposes. the Mid motor is still easier to drive but i wanted to see how consistency came into play. I haven't completely made up my mind yet. The RB6 is a strong car in either configuration.
cnelson3 is offline  
Reply With Quote
Old 10-09-2013, 05:57 PM
  #8395  
Tech Master
iTrader: (65)
 
Join Date: Apr 2011
Location: Wisconsin
Posts: 1,045
Trader Rating: 65 (100%+)
Default

Originally Posted by cnelson3 View Post
Thanks. I recently went back to rear motor for testing purposes. the Mid motor is still easier to drive but i wanted to see how consistency came into play. I haven't completely made up my mind yet. The RB6 is a strong car in either configuration.
I have yet to try rear motor with mine. I wonder how rear would feel with my 17.5. Chris- I'm curious to know more about your "findings". I'll chat with ya at trackside. (this is Nick M.)
nrm1977 is offline  
Reply With Quote
Old 10-09-2013, 06:04 PM
  #8396  
Tech Champion
iTrader: (73)
 
MikeXray's Avatar
 
Join Date: Oct 2006
Location: New York
Posts: 5,753
Trader Rating: 73 (100%+)
Default

Originally Posted by carbons2k View Post
Mike, try 0 degree hubs
Already did, moved the wheelbase 1mm shorter than middle as well. 521 arms and moving my battery back to inline from sideways are 2 bigger things I need to test, then I'm gonna go pluck that chicken
MikeXray is offline  
Reply With Quote
Old 10-11-2013, 09:38 PM
  #8397  
Tech Champion
iTrader: (73)
 
MikeXray's Avatar
 
Join Date: Oct 2006
Location: New York
Posts: 5,753
Trader Rating: 73 (100%+)
Default

Originally Posted by MikeXray View Post
Already did, moved the wheelbase 1mm shorter than middle as well. 521 arms and moving my battery back to inline from sideways are 2 bigger things I need to test, then I'm gonna go pluck that chicken
Tried a few of the changes, didn't get to the 521 arms, but moved the battery. Fwd inline def feels different, it steers differently and I kinda preferred it, I could feel less sidebite in the rear, and in 17.5 I needed that. I played with springs, went stiffer all around, seemed to change feel, but not a huge impact on lap times. I was able to win the club race, qual 3rd.

Last edited by MikeXray; 10-13-2013 at 03:57 PM.
MikeXray is offline  
Reply With Quote
Old 10-13-2013, 11:42 AM
  #8398  
Tech Regular
iTrader: (1)
 
Join Date: Mar 2012
Location: NYC
Posts: 254
Trader Rating: 1 (100%+)
Default

Originally Posted by MikeXray View Post
Tried a few of the changes, didn't get to the 521 arms, but moved the battery. Fwd inline def feels different, it steers differently and I kinda preferred it, I could feel less sidebite in the rear, and in 17.5 I needed that. I played with springs, went stiffer all around, seemed to change feel, but a huge impact on lap times. I was able to win the club race, qual 3rd.
hey mike can you please post a pic of your setup, im getting my kyosho ready for island hobbies and was thinking of swapping to mid motor. thanks.
glenng is offline  
Reply With Quote
Old 10-13-2013, 04:52 PM
  #8399  
Tech Champion
iTrader: (73)
 
MikeXray's Avatar
 
Join Date: Oct 2006
Location: New York
Posts: 5,753
Trader Rating: 73 (100%+)
Default

Originally Posted by glenng View Post
hey mike can you please post a pic of your setup, im getting my kyosho ready for island hobbies and was thinking of swapping to mid motor. thanks.
Here you go, I'm using 0 dg hubs now, even though the sheet has .5, if I run a faster motor, I use the .5
Attached Thumbnails Kyosho Ultima RB6 & RB6.6 Car Thread-rb6_mikel_irh_mm.jpg  
MikeXray is offline  
Reply With Quote
Old 10-13-2013, 06:30 PM
  #8400  
Tech Regular
iTrader: (14)
 
dmayhew25's Avatar
 
Join Date: Jul 2005
Location: Bakersfield, Ca
Posts: 453
Trader Rating: 14 (89%+)
Default

Been running the RB6 for about a month now and the car is very nice. Lots of good info in this thread. Thanks for all the good info everyone!
Attached Thumbnails Kyosho Ultima RB6 & RB6.6 Car Thread-image.jpg  
dmayhew25 is offline  
Reply With Quote

Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Terms of Service