Kyosho Ultima RB6 & RB6.6 Car Thread

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  • Quote: So I've been trying to get more weight over the rear axle to increase forward traction but despite running a shorty servo and moving the battery as far back as possible the best I could get was 38%/62%. A local Pro running a mid-motor B5m on my track has had good success with and recommended a 36% / 64% split. I would have had to add 90g directly over the rear axle to achieve this on my RB6!

    Naive as I was, I didn't realise that I could reduce the wheelbase by moving all rear suspension / hub shims to the rear! Reducing the wheelbase by 4mm and removing another 8g of mass from the front with Titanium Ball-studs, some drilling and more titanium screws / aluminium nuts got me to 36.7%/63.3%.

    Then by putting 21g of brass onto the rear bumper I was able to get to 36% / 64%.

    Now just need to add some mass under the battery (at the CoG) to get up to minimum weight! Can't wait to try it out at the track!

    You are getting wayyyyy to technical. Lol
  • indeed. just wheel it. practice will make up for slightly imperfect (as per the books at least) weight balance
  • The technical stuff is good to read though and does get the brain ticking
  • Hey guys, can someone post a pic of the revised (regular, not lightweight) alum chassis that has the extra battery post holes?

    I'll like to order one and want to make sure to get the revised version.

    Many Thanks!
  • Quote: Hey guys, can someone post a pic of the revised (regular, not lightweight) alum chassis that has the extra battery post holes?

    I'll like to order one and want to make sure to get the revised version.

    Many Thanks!


    I think this would be the "revised" chassis. It's what I got in my "world championship" edition RB6 Kit a couple of months ago. Maybe someone else can confirm that this is the "revised" one?
  • Quote: indeed. just wheel it. practice will make up for slightly imperfect (as per the books at least) weight balance
    Yeah, I think the fact I only get an opportunity once or maybe twice a fortnight to wheel the thing means I spend a lot of time thinking about it to get my "fix". I enjoy the thinking and tinkering almost as much as the driving.

    I just finished putting in some ACER ceramic diff bearings and AVID ceramic thrust bearing and man WHAT A DIFFERENCE!

    Before that I had the MIP steel bearings that come with the MIP Pucks kit and the diff felt very rough and grindy? I just assumed this was normal.

    Before putting in the ceramic bearings I took the time to sand the diff rings nice and flat/smooth with progressively finer sand paper over some glass. Now the diff feels amazingly smooth! Very happy. Not sure if this will affect how it drives but who cares when it feels this good lol.
  • Quote:

    I think this would be the "revised" chassis. It's what I got in my "world championship" edition RB6 Kit a couple of months ago. Maybe someone else can confirm that this is the "revised" one?
    Looks good. Cheers mate
  • Quote:

    I think this would be the "revised" chassis. It's what I got in my "world championship" edition RB6 Kit a couple of months ago. Maybe someone else can confirm that this is the "revised" one?
    This still looks like it has more milling than the original one I have. I could be mistaken but now I have to check. Maybe new kit time.
  • The original chassis
    That one does look slightly revised. Here is the original chassis.

    Kyosho Ultima RB6 & RB6.6 Car Thread-image.jpg  

  • Quote: That one does look slightly revised. Here is the original chassis.
    Lite weight chassis doing well for you? I've been running my buggy at 1535 grams with the stock chassis. Almost scared to remove any more weight.
  • I've gone back to the std chassis. I want the newest std chassis though. I think the lightweight is best for stock, not sure about mod.
  • Quote: I've gone back to the std chassis. I want the newest std chassis though. I think the lightweight is best for stock, not sure about mod.
    Care to elaborate? I'm running a 7.5 and have no plans on running stock but I was thinking about trying the lite weight chassis for more flex. I run on a medium grip black dirt track mostly but frequently run on a loose outdoor track as well.
  • Yeah Chris my RB6 is on rails. My car is working great at Rockford. I'm gonna come race with you guys in Milwaukee soon to see if the work I'm putting in is paying off.
  • Quote: Yeah Chris my RB6 is on rails. My car is working great at Rockford. I'm gonna come race with you guys in Milwaukee soon to see if the work I'm putting in is paying off.
    Very cool. Wait till you see my battery layout now. I gotta say, it's best feeling car I've had yet and lightest by about 65 grams!
  • Quote: Care to elaborate? I'm running a 7.5 and have no plans on running stock but I was thinking about trying the lite weight chassis for more flex. I run on a medium grip black dirt track mostly but frequently run on a loose outdoor track as well.
    I feel as though the LW adds grip, but almost too much. I found, after awhile, that the car would soak up too much in the chassis and not let the suspension work its magic as well. Anytime I stiffened up the car, the chassis would just flex more and it would be a little inconsistent. In stock you may not have this issue, and the 30g weight is probably well worth the effort, but in mod where the forces are increased and faster, it just felt a bit weird sometimes.

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