too much understeer

[varapis]

hi,

does any1 knows how to solve understeer problem to my hyper?

there is to much, especialy on high speed corners with full throttle.

thanks

Edited June 6, 2007 by varapis

[Michael.]

Maybe softening the front suspension, as I assume you're driving off road, so the front end will be skipping over bumps.

If not, lock the centre diff, take out the front driveshaft, and enjoy doing donuts with RWD...

[Garry]

hi,

does any1 knows how to solve understeer problem to my hyper?

there is to much, especialy on high speed corners with full throttle.

thanks

If its understeering on power, its transferred too much weight rearwards. Thus, you'll need to stiffen up the rear. Stiffer rear springs or screw in the droop screws a little on the front (do buggies have droop screws?).

[Ziggy122]

I found Firmer springs help a little all round

But the rear Tyres need to be set up like / \ (ie pointing inwards)

and the front need to be set up like \ / (ie pointing outwards)

I found the Stock was pretty much Straight Ie | | Front and rear

Just turn the Threaded shafts at the ends (take the wheels off etc)

Also you might wanna try putting them in different holes - this may also help

Ziggy

[Michael.]

Why would negative camber at the front help understeer at high speed? If anything I'd say do the opposite, and have the front wheels with positive camber ( / \ )

[Alexi]

Why would negative camber at the front help understeer at high speed? If anything I'd say do the opposite, and have the front wheels with positive camber ( / \ )

Maybe he meant toe in?

[bb2120]

Maybe he meant toe in?

I'm fairly certain he did...

Stiffen up the rear, give the front some toe out and perhaps soften the front if it's still under steering.

[Michael.]

Maybe he did, maybe he didn't... But if he did, then he would be right, and I would be wrong....

EDIT: wait a minute to prevent understeer, you'd want toe in at the front, and toe out at the rear....

Edited June 6, 2007 by Michael.

[varapis]

thank you all for the advice.

[bb2120]

EDIT: wait a minute to prevent understeer, you'd want toe in at the front, and toe out at the rear....

No... front toe out gives you more turn in but makes things more wobbly when going in a straight line

[adz06]

change servo lol my stock servo wouldn't even get turned on a average size road so i bought a cheapy one from lhs for like £8 seeing as its only for messing bought and it turns a lot better all most as good as my high torque ones

[Schumach3r]

i'd toe the back wheels in a bit, which would give less grip on the back and help it steer into a corner a bit better?

its been a while since i was into racing. lol

[Mel]

yeah you really need to speak to someone who races but you might be able to change the diff oils by using a higher weight in the rear so it sends a bit more power to the back end

[Garry]

i'd toe the back wheels in a bit, which would give less grip on the back and help it steer into a corner a bit better?

its been a while since i was into racing. lol

Other way round, rear toe-in makes the car more stable and harder to turn.

Handling/setup guide: http://home.scarlet.be/~be067749/58/

[fastboy]

if its a rtr could be many things.

first and foremost the most important thing is tyres tyres tyres,if your on the wrong tyre then no amount of tuning will get it right.

stiffer rear springs and thicker rear roll bar will induce more high speed steering,more antisquat on the rear and less rear toe will also help.

more castor should give you better on power steering exiting a corner,running toe out on the front gives more initial turn in but less coming out of corners,toe in is the opposite.

a thinner front diff oil may help but dont go below 5k or it can get a bit inconsistent,7-5-2 is a good starting point.

try white springs all around with 40 upfront and 35 in the back.

move the rear shocks to the outside hole on the rear wishbone,move fronts to inner hole for more steering all round. try taking some droop off the front(yes they do have droop screws garry ,but not too much if its a bumpy track,im assuming your racing on dirt?

dave

Edited June 7, 2007 by fastboy

[Michael.]

More toe in means that as the car shifts it's weight onto the outside front wheel (which is more 'turned' as it's toe'd in), the car will turn better. Toe out on the rear works similarly.

Toe out at the front increases stability and reduces 'turning', especially at high speeds (where the car shifts it's weight more)

[fastboy]

no..toe out makes the car more unstable and twitchy,the inside wheel has much more hook due to the ackerman effect.

[Michael.]

Ok, I'll wikipedia it or whatever, and return with my findings. Although I can tell you, on a track, in a real car, Toe in at the front makes the car turn better

*opens wikipedia*

[Michael.]

Ok after some quick research my findings are;

Toe in at the front makes the car more stable in a straight line, and initially harder to turn, but as the car rolls more, and the weight balance shifts to the outside wheel, toe in is better than toe out (at the front)

Toe out at the rear decreases stability, and helps turn in.

And yes the Ackerman effect is the reason for the increased turn initially

So basically, toe in is good for curing understeer initially, but it's effect is diminished at higher speed corners, and rear toe out just prevents understeer full stop

Edited June 7, 2007 by Michael.

[Garry]

You should never use toe out on the rear of a car.

In RC use (from the guide I posted):

Rear Toe-in This is one of the most sensitive adjustments! One degree goes a long way.

Stabilizes the car greatly. It makes the rear end 'stick'. The more toe-in you use, the more the rear of the car sticks. This is especially apparent going into and coming out of turns.

But more toe-in makes the difference between sticking and breaking loose bigger.

Large amounts of toe-in (2.5 ... 3 degrees) scrub off a little speed in the straights.

Rear Toe-out Rear toe-out is never used. It makes the rear of the car very, very unstable.

Front Toe-in Stabilizes the car in the straights, and coming out of turns.

It smoothes out the steering response, making the car easy to drive.

It can make the car turn a little more in the middle and exit parts of a turn.

Front Toe-out Increases turn-in steering a lot.

But can make the car wandery on the straights.

Never use more than 2 degrees of front toe-out!

[Michael.]

So it looks like unless you have a full pit set up, adjusting your rear toe is something to avoid.....

[Garry]

Same with any toe, front or rear. if its not 100% identical left to right, its not going to handle right.

[Ziggy122]

i found if 1 toe is out - i get alot of tugging and fighting with it while cornering

And i pulls to a side when going in a straight line

Ziggy

[geo-hovis]

When i softened my rear suspension up my car understeered alot more than it used to do. But dunno if i should keep it like it is as it handles the rougher field (where I normally race) better

[Garry]

You could try adding more caster by changing the front hub carriers, should help it.