bradshawkyle

iTrader: (3)

Christian,

I ran my RSD6 for the first time last week and was blown away by how consistent the car was in the corners. I'm pretty new to 17.5 TC, but have more time under my belt in VTA, and with the new chassis I set personal best times all night long. I'm using Mike Gee's setup from the RSD6 info page on an otherwise standard TC6.1 with Reflex bladders + pistons and have a couple questions if you don't mind:

1) The dual bellcrank system doesn't seem to have nearly as much throw as the single bellcrank - is there any way to increase that? I maxed out the throw in my radio and it's decent, but would like to get more mechanical travel if possible. If not more travel, then I assume the next step would be to add shims on the bellcranks to decrease ackerman, right?

2) While the car rotates nicely and is extremely predictable in the corners, when I come off a right-hander onto the straight it almost always walks toward the right side of the track. It's a smooth arc tat never seems to get worse, but the only ways to correct it are to turn-in to the slide or let off for a second to settle the car. It feels like the rear end breaks loose a tiny bit and I'm wondering of the 3.5 degrees of rear toe is creating too much slip angle. Any thoughts on how to calm it down and run straight? I have checked for tweak, BTW and everything seems straight.

Thanks,
-Kyle

geeunit1014

iTrader: (14)

1) You should be able to achieve the same amount of throw with the DBC. Which servo saver are you using? If it is too short you wont get enough travel. Im using a kimbrough mid size in the tall holes (the upper outer ones), and im at ~90% d/r (100% epas) on a futaba tx to get 5ft turning circles

2) 3.5 rear toe is more stable than 3, trust me on that If you want to make the car a little more stable on exit, add anti dive to the front (change the rear front blocks to 0B). I would also double check your front toe on setup gauges just to be sure.

grippgoat

iTrader: (8)

Kyle,

3.5 is an awful lot of toe-in for 17.5 at the Hangar. I'd drop to 3.0 and go from there. Reducing the rear toe-in will lengthen the rear wheelbase just a touch, shifting a wee bit of weight forward. I've definitely had moments where I took my tail-happy scale spec car, and removed .5* of rear toe only to find that it planted the back end and made the car way better to drive.

Also, if you're feeling like you don't have enough steering throw, it may actually be that your car is really pushy and you're trying to get around that by cranking the steering.

-Mike

bradshawkyle

iTrader: (3)

Son of a biscuit! I just realized I have an itty bitty one on the car. OK, that makes perfect sense. I need to get a bigger one, thanks for the help.

Thanks, Mike. The car doesn't seem to have any understeer issues, I measured the throw on my setup station and when compared to my Scale Spec car it's getting 15 degrees at 150% in the radio versius 17 in my Scale Spec car at 75%. Other Mike is right, I need a bigger servo saver. <facepalm>

The stability issue is definitely a butthole-puckering experience, one I'd like to eliminate. Currently I find myself lifting to settle the car when others are nearby so I don't wander and take them out.

CristianTabush

iTrader: (13)

Kyle, which car is unstable the TC6.1 or the RSD6?

Thanks Mikes for jumping in...

geeunit1014

iTrader: (14)

I would suggest adding the front antidive, and you may also want to try a RSD red spring up front. Ive been wanting to try that for a while, and hopefully will this weekend.

bradshawkyle

iTrader: (3)

Hi Christian, thanks for the help. The RSD6 is the one giving me a heart attack while running down the straight. Any input would be greatly appreciated.

CristianTabush

iTrader: (13)

You are running on carpet correct?

If the car is not going straight, you have an alignment issue somewhere.

Try securing the servo in place with some servo tape or shoe goo additional to the servo hold down. On carpet, I think using shoe goo is the way to go. It helps the car track more straight.

Measure your steering links and make sure they are the same length. Also, make sure none of your bulkheads are slightly misaligned. This can happen, and it is impossible to tell with the blind eye. So just loosen everything up and re-set it.

Also, take a look at the set-up I have from the Texas EOS rd. 3. I worked on getting a car that was extremely neutral. Mike's set-ups tend to be pushy going in and then have a lot of steering and rotation. Maybe all the rotation is causing the car to be hard to drive coming on to the straight. I know that when my shocks are standing up too much, I have a hard time keeping the car going straight.

Lastly, check your rear diff, your blades, and your tweak on a tweak station. Also check for breaks or fissures on your caster blocks.

idbdoug

iTrader: (41)

At the recent Texas EOS rd 3 race, my car was also twitching coming onto the straight out of the corner but very goog everywhere else. Ralph Burch said I was running the car too flat, so I increased the rise front and rear by .5mm and the car was awesome. I run a different brand but I would think trying the increase in rise on both ends would apply
idbdoug

CristianTabush

iTrader: (13)

Very true Doug. Thanks for the help. I was running 6f/5r droop which is like 2mm of rise in the front and 3mm in the rear.

wiggindude6969

iTrader: (1)

My set up at the EOS Rnd 3 was the same as everyone else, except I was running Red/Blue Springs, 2.5 Deg Toe In/Rear. Same droop 6/5 ride height 5.5R/5F. My car was dialed, but I am just getting back into RC.. I actually had to Dial out Steering. (i run my front hubs upside down, seems to work better for me... and i like the car to push some..)

I got my car about 5-6 weeks ago.. Cristian helped me set the car up for M&M in Houston (ashpault ). The only thing i changed to go to Mikes in Dallas was the Springs. RSD6 is the best car i have ever owned... hands down!

I changed to the longer servo horn about 1 week after i go the car and it added more steering.. Just make sure you check screws that hold the servo! If you hit somthing hard... they can come loose and this will cause the car to veer like your talking about. I had this happedn in a qualifier in Dallas.. Adding servo tape under the servo will help keep the servo stay in place. The other thing i noticed is if they apply some type of traction adative to the track and you get half the car out of the line... tire build up on one side of the car will cause this...

my 2 cents.. Good Luck..

grippgoat

iTrader: (8)

I mis-read your initial post. I thought you were talking about coming off the straight, not onto it.

Is the problem that the car doesn't drive straight when you're on throttle? Or is the problem that the car wants to keep turning when you're getting onto the straight? Or is it that the back end is kicking out when you get on the power?

If the problem is that the car just doesn't drive straight on power, it's most likely a tweak issue (uneven droop, something binding, bent hinge pin, uneven spring preload, uneven static weight balance, sticky bearings, etc). Small amounts of droop like the setup you linked can definitely exacerbate a tweak issue.

If the problem is that the car doesn't want to stop turning, the large amount of servo travel you're using could be contributing. I've got some other ideas we can check at the track, too.

If the problem is the rear end kicking out, I'd start by checking the rear diff to see how tight/loose it is. EDIT: Also belt tension. If the rear belt is tight and the front is loose, that can make the back end kick a bit when you jump on power.

Are you running a spool or gear diff in the front?

Anyway, I'm betting your issue is that something in the setup / prep is cranked to 11, possibly by accident, and you just need to find it. My entire second season of racing was spent largely learning about all the ways I can screw up a setup, and how to not make those mistakes so that I can put a car that will handle the same way down on the track every round.

-Mike

snoopyrc

iTrader: (2)

Christian I want to thank you for supporting the USVTA Southern Nationals in Nashville TN. I was the lucky recipient of your contribution. I have been following this thread and it looks like I will be among the RSD drivers very soon.

bradshawkyle

iTrader: (3)

Very helpful, fellas, thanks so much. I have a laundary list of items to check and possibly change, I'll post back when I figure out the cause.

CristianTabush

iTrader: (13)

Awesome! Welcome to the club. If you have any questions, post away!