How to stop that Tail???

[Cy]

:o

I have one Yokomo SD (brand new) and I start to drive him on Carpet. Everyhting is great but the rear is just not staying planed....
and I hate the guys saying my front has a lot of grip...
I just want to plant my rear. But HOW?
I am using the original springs (silver), 3°toe-in at the rear and the rear shocks are with 35°oil and the original Springs.

Does somebody knows what to do since my yoko rear tray allways to overtake the front at the middle of the curve?

Thanks in advance

Pedro

[cobra81li200]

To start, use thicker oil. I've tryed 35W and it just didn't work for me (quite the same problem as you), when I went to 55W, it was just much better.

Next, I've found that the std springs are ok for outdoors, but not for indoors. If your track is quite flat, then try green on the front and yellow on the rear.

Finally, try adding some camber on the rear (gives more grip), and link your front turnbuckles on the middle line (i.e. the "center" hole) of your suspension mount (give les grip but more traction) Don't forget to adjust your turnbuckle lenght.

[nitro-head]

i found i had this problem with kit springs.
i put green on the rear and orange on the front.
40wt all round. 2 degrees toe in, 3 degrees camber on the rear (and can't remember what is on the front, lol)

this is for indoor, no sway bars (that are useless anyway)

may i ask a dumb question?
what is the differene between grip and traction?

[cobra81li200]

grip is overall.

I might have said : in corner grip. It's the capacity of the concerned train to stick to the ground during cornering,

Traction is the capacity of the concerned train to transmitt the power to the ground...

[lotusmark2]

I run a 4tc belt drive but with a carbon top and bottom deck very like the SD.
I found the same issue with mine was cured by 50 wt oil all around number 2 pistons.
I run quite a bumpy indoor circuit so I run blue fronts and white rears with 3 degree toe in and 2 degree camber on the rear and 1 degree toe in and 1 degree camber on the front.

[nitro-head]

i thought that the rear end kicking out would be caused by lack of grip at the rear and too much at the front. putting 50wt in would make it worse i think. because you are just making the back stiffer yet.

also what i did, i took out the 2 middle stiffener posts (ones going down centre of the chassis) i thought the chassis was a little to stiff, i took these out and it make a vast improvement

[lotusmark2]

The oil effects the damping rate (the speed at which the shock reacts) not the pressure it takes form the shock to be compressed, that is what is controlled by the springs ;D

Have a look at
http://www.quarterscale.com/suspension_101.htm

[lotusmark2]

If anyone is interested I can email through an RC setup bible that covers every aspect of rc setup and to be honest more than most of us will ever need.
Drop me a PM if you want.

[cobra81li200]

Mark,

I found out to have the same setup for springs and ol as you on my indoor bumpy track, but with a SD, quite funny...

35W is just too fluid for the SD (check all the drivers uses at least 50W).

[sosidge]

Cy - have you built the cars with the shocks at 60mm (as suggested in the manual)?

For most people that is way too short - you could end up with very little or no suspension droop - and this will take away grip and make the car feel inconsistent. I run my shocks at 63mm front and 62mm rear by unscrewing the ends and adding plastic spacers to cover the screw threads.

I've found that the SD is by nature a very stable car, prone to understeer if anything.

[nitro-head]

yes, i found that to.
i run my shocks at 63mm on front and 64mm on back. runs ok for me. i might try 55wt oild next race meeting thought, a few people say it works well.

[Cy]

;D

Thanks for all the great help.
I know some other forum, but this one is great.

I will try it this weekend.

Servus

Pedro

[richyrs2000]

Hi all,

I had this problem the first couple of times i used my SD, it was built per manual, i seem to have understeer switching to really bad oversteer. With the help of Merv and Ian this is the cure, which at Carpet masters gave too much grip, but hey you don't hear that very often!!!.

1. Both roll bars conected

2. 45 oil front and back

3. Associated Gold springs on the front

4. Associated Silver springs on the back.

By the way don't believe all you hear the associated springs fitted straight on with no problems at all.

All the dampers were as upright as i could get them with 1º neg camber all round. 3º toe in on the back and about 1º toe in on the front.

It should be noted though i still drove like an idiot!!!

[sosidge]

Hi rich - that inconsistency from understeer to oversteer was the big problem I had when I first got the car. I never ran the roll-bars, what I did is to run the front wishbones in the lower holes on the c-hub (like most of the team setups suggest), just keeps the car's balance more consistent all the way around. You lose a touch of steering, but it's worth it in my opinion.

[wrx]

hi all, i "helped" set rich's car up,
i think 2 of the most effective changes we made were to:-

1. make the rear camber link longer, (can't remember if we moved it at the shock tower or the hub now), and

2. make the wheelbase shorter at the rear by moving the spacers on the hinge pin, only move 1 thin spacer at a time, otherwise you can loose all of your steering as rich found out.