Balance between camberlink length and roll stiffness.


Driving on extrem high bite carpet indoor tracks or ultra high bite astroturf tracks the rear weels of my b4.1 wears more on the outside.
So in corners there is not enough camber gain.

There are two options to get more camber gain.
1 - shorter rear camberlinks
2 - less roll stiffness

An last practice day i tryed both options.
- Shortest possibel camberlink. Tire wear looks much better, but car feeld crappy.
- Go back to old camberlink length and reduce roll stiffness. Tire wear looks better, but car feeld crappy.

An experts told me on extrem highbite tracks like carpet or astoturf camberlinks long, some times the longest possibel position and high roll stiffness (high rollcenter). And live withe the uneven tire wear.

I thing there is an balance point between camberlink length an rollstiffness.
My problem is to find this balance point.

How to find out this balance point?

Sorry for bad english

When you say the car felt crappy can you elaborate? I'm guessing it wallowed in the corners and just felt kind of sluggish. I see the same thing on my SC10 on carpet. I think part of it is the layout of the track too. With our track designed like it is both of the sweepers are turning to the right and the left rear wears more on the outside of the tire. You know the ride height is going to play a strong roll in determining how much the car rolls. Maybe you could tinker with the ride height with your shorter link or lower roll center settings and see if you can make the car feel a bit less crappy.

One piece of information that is missing is the amount of camber you are running. Don't go too extreme of course but if you are having a bit of wear on the outer parts of the tires but like the handling with the camber link position, try leaning in the tires a little bit. Up to 3 degrees. Keep in mind also that with different amounts of roll stiffness, the tires will react differently. One setup may favor a softer foam insert where the other favors a firmer one.

We were able to clearly convey your point.... your english is as good as 90% of the people that were born here! I'm sure most of us can't say the same for our (insert foreign language here / German)... We cant even speak Canadian. AAyyhh?

Bingo on the camber Fred. My son had been struggling with his truck and bit and jacked the rear camber up to -3° and now loves it. He's got a relatively new set of dBoots Terrabytes on it. I'll check the tire wear this evening when I'm up in the shop. I know I fluctuate between -1 and -2° but have been hesitant to go further for some reason.

If you can use terms like "crappy", you are doing just fine with the English language. Ich mag Bier und Pizza, aber die Behandlung meiner SC10 ist beschissen.

As a german I can confirm that und natürlich mögen wir auch rc autos

haha, actually we'd use the term handling in german too xD But not bad for your first try It is really becoming a problem that I read so much in these forums, because I often only know the english word and people here don't know what i mean

@Peter Dietrich: I'd say if you can read and understand what people write in this thread, you're at least better than 95% of the other students in my english class. No wonder they don't get any better if they only read storys that have been translated by other germans who don't know what the hell they're doing.

OT: still trying to figure out why my truck is traction rolling... Must be the tires, i tried everything and nothing really helped. Of course it got better after a few changes, but not as good as i'd like it to be.

@ fred with the old setup i tried rear camber between -2 and -4.
Rear camber with the extrem short camberlink setup and the deep rollcenter setup was -3.

@bds test with both setups was last year. I cant remeber exactly what was "crappy". But i remember with the extrem short camberlink setup in corner entry the car understeers and in the next moment ( in the moment where the grip on the front weels come back) the car extrem oversteers. The understeer oversteer problem was in tight 180 degree cornes driven complete offpower.

Since I'm a bit unconventional, one thing I mess with is the diff setting. My tuning generally gives the car more than enough steering. I usually dial a little bit out by running a tighter diff (thicker oil) which also has the benefit of putting the power down more equally as well.

With a spring/shock combo that results in suspension balance, and with modern cars with equal length arms front and rear, I will generally try to get the front and rear roll centers as close to each other as possible. In a perfect world they'd be the same. If I have 3 degrees of camber gain in the rear, I want the same at the front. With a 2wd vehicle, there is a heavy rear weight bias so steering is not a problem. More rear bias inherently gives more steering, not less. If I have too much then I'll go tighter on the diff to dial a bit out.

Hideeho
The one time I raced on carpet I was having traction roll problems & was given the recomendation of putting super glue 1/2 way up the side wall of the tire. This seems like a temporary bandaid, but it worked like a charm!

p.s. I'm feeling left out on the foreign languages. The only German I know is:
Du
Du hast
Du hast misch...

so im hoping to get a bit of info here.

its been a while since ive driven offroad and the last few months it wasnt all that enjoyable. my truck seems to have a weird thing going with it as if "it steers" with the back end. truck coming out of turns wants to wash out the back end and off throttle a bit as well. then when i roll into the brakes seems as if all the weight goes to the front, picks the back end and swings out.

camber links are in this order..

front.

camber links are both inside (short) inner side and outter side
no spacers for ankerman
top shocks are layed in and lower shock position is middle

rear.

camber links are middle rear innner side and outside hole outter side.
shocks are at middle hole top and outter side lower hole.

40w front oil and 37.5 rear.

using kyosho yellow rear xring spring and red fronts. i tried stiffer front end to prevent the weight going to front under braking but didnt help. i also think i may have too much camber gain as the inner part of the tire gets eaten quick.

Go back to page 2 and start reading to see how to learn how to set it up.

Try shock limiters. I would start with 2mm front and rear.

Gear diff or ball diff? If it's a gear diff you might be running too stiff an oil. If it's a ball diff it might just be set too tight or it may need a rebuild. This sounds a lot like what happens when a ball diff needs a rebuild.

I already glued the side of the front tires, but it didn't really help. Tires like the schumacher minipins have a relatively hard side, so the tire really slides on the glued part, but the Dboots which i use are very soft, so the side of the tire gets compressed when the car is about to flip. I know have it set up to have a lot of camber gain, so the tires don't reach that "flipping point" too soon, that makes the traction rolling a bit more predictible but at the same time you gain even more sidebite.

@jsk: do you mean droop limiters? i have the droop set to arms level

I already glued the side of the front tires, but it didn't really help. Tires like the schumacher minipins have a relatively hard side, so the tire really slides on the glued part, but the Dboots short course tires which i use are very soft, so the side of the tire gets compressed when the car is about to flip. I know have it set up to have a lot of camber gain, so the tires don't reach that "flipping point" too soon, that makes the traction rolling a bit more predictible but at the same time you gain even more sidebite.

@jsk: do you mean droop limiters? i have the droop set to arms level