RB6 low grip battery config/options help

[Chris Elworthy]

Hi lads,

My RB6 is hands down the best 2wd I've driven in high grip but I am finding myself being very off the pace when the track is wet or low grip. The car feels ok on corner entry but washes out badly on corner exit regardless of how smooth I bring the throttle back in.
My car is still set in the standard config with speedo at the back (Orion r10) and saddles in the middle. Is this how people still tend to run the car in low grip or is moving the speedo to the front allowing the batteries to be placed further back be the way to go?

I recently changed the rear lower shock eyelets from the kit long ones to the medium ones to reduce rear droop and get a more planted feel while running on high grip astro, would putting the standard long eyelets back on be useful in low grip- I'm not too sure on what droop does to this car.


Any info would be greatly appriciated


Chris

[Neil Skull]

Hi Chris,
If traction is low it helps to get weight back to give rear grip to the wheels driving the car forward, But if its greasy track then it will make the rear more wild. More droop will help! and just a softer set up and I guess most guys will run a higher camber link all round! I leave the pro drivers to confirm that!

[Chris Elworthy]

Thanks for that Neil, hopefully somebody else can offer some other setup advise.

I'm racing at Kidderminster this weekend for the first time which I'm told is rather slippery when cold/wet so I'm torn as what to do?

I find your comment that the weight too far back can make the car wild? This seems strange? Is it due to more of an aggressive weight transfer from back to front?


Chris

[h0m3sy]

Why not give the RM configuration a try?

[discothesnake]

Hi mate, i tried this layout and found it made a big difference. A bit more understeer but backend was planted.

[InsideLineModels]

Hi Chris,

Here are a few things i'd try.

• Short wheelbase - if you are running RB5 rear wishbones (which will help by themselves) flip them over, this ill reduce wheel base by 3.5mm ish. I run on long wheelbase (1.5mm shorter than normal short) when the wishbones are flipped. It's rare i do this but i did run it like that at the Kidderminster national as it is super slippy there.
• have you drilled the extra inside hole on the RB5 rear arm? This will help drive but also get the car into the turn quicker. I run this position pretty much everywhere.
• lowering the inner links front and back will help. I tend to vary between 2mm and 4mm on the front (4mm - high grip). On the rear I change between 2mm and 0 (0 on low grip).
• Shift weigh back - although for me if you loose to much steering you find yourself trying to force oversteer with the throttle, which can be counter-productive.
• More rear droop should settle the car down whatever the condition, I tend not to touch this much at all and i run a fair amount.

I hope some of that helps

Kev

[tomtom]

Thanks Kev, very nice tips !

Did you still drill a third hole on wishbones if flipped over ?

I tried 0.5 hubs and some flap on the wing (almost full gurney) and it was safer.
Also prefer Ballistic greens over Silvers on wet astro (more drive and safer on corner exit).
Got to try C inserts on RR block.

[Chris Elworthy]

Thanks for the advise Kev, I will give the car a try with the speedo at the back for this meeting then maybe try the cells back at another round. I'd like to be able to get the car to work with cells forward in low grip as my local tracks are very high grip so the cells back setup makes the car very pushy.

When you say flip the arms do you mean turn them around so the front of the arm now faces back or flipped from top to bottom? I haven't yet ran the RB5 arms on my car as a mate of mine who has been running both the 5 and 6 arms told me he feels the gullwing arm "digs in" more which he feels helps in low grip but I will give it a go. Would a similar effect on drive be achieved if I was to drill an extra hole in the rb6 arm also?

Finally, do you do anything to your speedo settings to help in low grip? I've been told reducing the deadband on my Orion R10 would bring the power in more smoothly?


Thanks,

Chris

[InsideLineModels]

Originally Posted by tomtom

Thanks Kev, very nice tips !

Did you still drill a third hole on wishbones if flipped over ?

I tried 0.5 hubs and some flap on the wing (almost full gurney) and it was safer.
Also prefer Ballistic greens over Silvers on wet astro (more drive and safer on corner exit).
Got to try C inserts on RR block.

Yes, I do run the additional hole even if flipped.

The new hangers with the inserts are very good for fine adjustment of the inner toe angle and wheelbase. At Oswestry national (grass track) I ran an additional 0.5 degree inboard toe (3.5 total) which also helps by shortening the wheelbase also.

To be honest, if you have these hangers you may not need to flip the wishbones, but i've not had much chance to play with this yet. UMW505 and UMW507 are the mid motor hangers and UMW506 for Rear motor.

[InsideLineModels]

Originally Posted by Chris Elworthy

Thanks for the advise Kev, I will give the car a try with the speedo at the back for this meeting then maybe try the cells back at another round. I'd like to be able to get the car to work with cells forward in low grip as my local tracks are very high grip so the cells back setup makes the car very pushy.

When you say flip the arms do you mean turn them around so the front of the arm now faces back or flipped from top to bottom? I haven't yet ran the RB5 arms on my car as a mate of mine who has been running both the 5 and 6 arms told me he feels the gullwing arm "digs in" more which he feels helps in low grip but I will give it a go. Would a similar effect on drive be achieved if I was to drill an extra hole in the rb6 arm also?

Finally, do you do anything to your speedo settings to help in low grip? I've been told reducing the deadband on my Orion R10 would bring the power in more smoothly?


Thanks,

Chris

My opinion is that the gullwing wishbones help the car rotate on power, and that is what you want to try and reduce to some degree on low grip. Try the RB5 arms, that will be the biggest change you make. I tried an extra hole on the RB6 arm but didn't feel it was need on that.

Just for information you would need two packs of any of the following (they all come with the same rear but have a different front)
UM566
UM521-1
LA272

I don't really play with speedo settings much once i've found a good base. All I normally change is current limit and boost depending on grip level and track size.

[RogerM]

Totally agree with everything Kev has said there!

If you want to come over and see me at Kidderminster I'll give you my full setup and even drill the RB5 arms for you if you need them doing. To run the full setup you will need to put Losi Pink springs on the rear and X-gear Yellow on the front (sometimes run Losi green - softer or Losi blue - harder, very occassionally X-gear orange - harder again but mainly for high grip situation). Oil wise it is Kyosho / Core 500cst front, 350cst rear, pistons wise 4x1.3 both ends (one hole blocked in the standard pistons).
Wishbone wise I'd go for the UM521 as I have found in some situations going back to a standard RB5 front wishbone & hanger combination helps calm the front of the car down, it's rare I've needed to do this but say on super high grip it has helped.

If you want a 2nd opinion on my setup you can ask Adam Urbanowski who has run on a track that was low grip in the wet and stupidly high grip when it dried out and he just shifted a bit of ballast weight around made a very minor change to roll centre, car dialed.

Seems to work really well eveywhere.

Also BigT and Ben Pugh will be running my setup too (Ben just got his RB6 and I put the setup on it for him last wekeend, going more than a 2nd a lap faster with it than his old Losi 22).

If you don't have the ali rear arm hangers then I recomend them, if money is tight just get the forward one (but both have merit).


Hope that helps.

[Chris Elworthy]

Thanks Roger, and Kev earlier,

I intended to get hold of some rb5 rear arms but my LHS only have one set in stock and is a little late to have any delivered by Saturday so I may have to persevere with the standard gullwings for Sunday if I can't source any quickly.

My stock oil setup is very similar to yours with Core 500 front and 350 rear with Losi pink springs on the rear and Losi black fronts in high grip, I often switch to blue fronts and yellow rear Losi springs in low. I have dropped my rear oil to 300 core for this Sunday and use standard pistons all round.

Am I right in thinking the standard rf2 block offers around 2.7 deg of toe in? What degrees can be achieved with the adjustable blocks? If the front block to replace Rf2 alters toe angle what would changing the rear block do? Track width?


Chris

[DaHomie]

Hi Chris,

this over at Petitrc will give you most details regarding the new hangers:

http://www.petitrc.com/setup/kyosho/...5UMW706UMW707/

Cheers,
Roy