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totalazneclipse
2008.11.26, 10:57 PM
I wanted to know if the caster kit was essential to having a complete setup on the 02's and I also wanted to know if you guys oil your bearings regularly. I'm still learning as far as Mini-z's go but I have some knowledge from 1/10th scale.

Thanks in advance.

cowboysir
2008.11.27, 01:00 AM
What i know of a "caster kit" is replacing the top arms with an alloy tower bar with a preset caster machined into it. I honestly can't remember the physical characteristics on what caster does to a mini-z (or any scale for that matter) but I find of my cars that have tower bars with a .5 degree caster they tend to be stable in high speed corners (for my limited racing knowledge at least).

As for bearings, some will say light lube and some will say dry (no lube)...I support both theories in cars and i don't notice too mcuh difference (it's probably just my limited skill again):D

totalazneclipse
2008.11.27, 04:21 PM
Thanks for the help cowboysir

rickyb
2008.11.27, 06:44 PM
i like to run .5 deg caster for stock and 1 deg in mod. i clean my bearings everyweek with motor spray. fill up a tube with spray and shake it for a while. (vibration gets the junk out) then use some trinity bearing oil and your good t go!:cool:

Slipstream
2008.11.27, 11:56 PM
Caster is another tuning option. It helps with stability because the front wheels will tend to self center. Caster also gives you camber rise. As the front wheels are turned the negative camber on the outside front wheel will increase. When setup correctly this is supposed to keep the tires contact patch to the ground centered on the tire and as large as possible when the car leans.

With new bearings I always degrease then lube them with light oil (I use Glidex) before I put them in. It gets rid of the drag from the thick grease that most bearing come with. I would clean and relube them if they look really dirty or when you tear down to do maintenance.

totalazneclipse
2008.11.28, 02:03 AM
Cool. thanks slipstream.

ianc
2008.11.28, 04:04 PM
Caster also gives you camber rise. As the front wheels are turned the negative camber on the outside front wheel will increase.

I'm trying to work out why this would be the case, but I can't. I don't see how caster (which is the fore\aft inclination of the kingpin) would cause the camber to change at all. Can you explain?

ianc

Slipstream
2008.11.28, 09:59 PM
I'm trying to work out why this would be the case, but I can't. I don't see how caster (which is the fore\aft inclination of the kingpin) would cause the camber to change at all. Can you explain?

ianc

Caster have only a truly fore/aft inclination when the wheels are pointed straight ahead. Once the front wheels start to turn, the inclination will have a side tilt component.

Look at a larger scale rc car with caster/no camber from the front grill view into the car. When the wheels are point directly straight ahead, the full width of the tires touch the ground. Turn the wheels while still looking from this view and you'll see the outside edge of the outside tire lift off the ground giving you negative camber ----> camber rise from caster. More caster = more camber rise.

When setting caster with neg. camber you have to take into account how much your car will roll ----> softness of the springs. You want the largest tire patch in the middle of the tire for max. grip, but you have to decide where in the roll and turn you want this. Near the beginning of the turn, in mid corner or at the end of the turn. You can't really have the max contact patch throughout your whole turn.
Set up properly with the way you drive and you'll also get even tire wear.

ianc
2008.11.29, 01:15 AM
Caster have only a truly fore/aft inclination when the wheels are pointed straight ahead.

OK, having considered this, I think I have reached an accomodation with myself as to the dynamics involved. I don't have a larger scale RC car with caster but no camber to check, but I don't doubt your word. Thanks for the explanation,

ianc

rickyb
2008.11.30, 10:30 AM
i've found that the easiest way to explain caster is, the more caster the slower the car will turn in. (react) it will also settle the car upon acceleration and make it more stable down the straits almost like toe in.

totalazneclipse
2008.12.02, 03:49 PM
that's guys. everyone's explanition helped a lot. Now I just need more track time...

Slipstream
2008.12.04, 08:56 PM
OK, having considered this, I think I have reached an accomodation with myself as to the dynamics involved. I don't have a larger scale RC car with caster but no camber to check, but I don't doubt your word. Thanks for the explanation,

ianc

ianc no worries about doubting me. At least I know you're reading my posts. :D