I've been racing my buggy for 6 months now and i can't find the best setup to keep me on rails.
It seems that my friends MBX 5 is never oversteering no matter how fast he goes((and he doesn't know how to drive)).

The track is bumpy,and i tried evrything(almost).I changed from 35w shock oil to 20w,which helped a lot,BUT NOT that much.

The rear of the car is NOT controlable,when ON power i loose it.
And when OFF power it's not turning as i want it to.
IS MORE LIKE:
ON POWER-OVERSTEER
OFF POWER-UNDERSTEER

WHAT CAN I DO?Any thoughts?
-caster,-camber,-toe,-shock oil,-diff oil,...

Sounds like a diff oil issue to me, try something stiffer in the front to pull you through the corners...try taking off the ARBs if you have 'em...what's your friend with the mugen got in his diffs?

He knows nothing on diff oils,shock oils nothing...And notice that he had a Kanai sp1 and sold it cause he couldn't drive it and got the mugen and this car is a train...

My diff oils are 7/10/3--front/mid./rear.

Hmmm, already seems pretty strong on the front then, but I still believe you can get some improvement by messing around with the diff oils, maybe even stronger on the front, lighter in the middle, and a lot lighter on the back...also if you have a lot of anti-squat on the front, that will cause off power oversteer (but helps prevent bump-steer). I'm not surprised your inexperienced friend had trouble with the Kyosho, they are supposed to be very aggressive on turn in, requiring a good technique, some people describe it as 'squirrelly', but that's 'cos they can't handle it...once again, I'm drawing from my on-road and full scale experiences, plus other people's experiences and what I have read...buggy still not here... [:@] ...take a look at some pro setups, try a few different things...especially with and without any ARBs you might have...

ARB???? It's the sway bars that you mean right?

Yes i do have one up front which is a no no on bumpy tracks BUT my problem is rear traction on power and front when off power.I assume the sway bars give traction to the opposite site!

Need more info buddy!!![]

chris,
Post you complete set up
front-
camber, toe, shock position/oil wt.
Standard diff?

Center-
Standard Diff w/10k oil?

rear-
Camber toe, shock position/oil wt.

Also what exacty is the rear doing in?
spinning out or bouncing around?

front 0degree camber,1-2degree toe in
rear 3degrees camber,3degrees toe in

both shock positions are at lower out hole and upper middle
with 20wt oil

std diffs front rear and spider center
7/10/3 oil front-mid-rear

And the rear is mostly spinning out!!!

Wow, you're all screwed up

1-2 toe in front??? you should have 0-1.5 toe out
try starting around 1* toe out with -1* camber
5k diff oil and about 40wt shock oil

center run about 7k diff oil (maybe less with the spider)

rear
-3* camber is too much IMHO (your tires aren't touching much dirt)
try about -1* camber also with the stock toe setting for the pbs car
35wt shock oil and 1k diff oil

try that and see if it's more driveable, this is very close to my set up and I never spin out

I don't have a setup kit,is there a simple way to do things.It might not be as i want it to but at least something close.
I've seen something with a ruller but i can't find it!

I run 3-7-1 front to rear. I have 35wt front and 30wt back with white hobao springs and 1.5 mm holes.
I'm also unsure of the toe/camber. I just have it set up so it looks right.
I don't race much but my car seems to handle well on bumpy ground.

Just get a RPM Camber gauge less that $10, or carpenter's type angle finder.

You can adjust the front toe by rolling the car against a vertical surface and holding the gauge horizontally against that surface

I can take photos and walk you through how to do it if you want

Try running lighter diff oil in the center. Especially with the Spyder diff. I'm running 7K in the center, and don't want it a bit thicker. I run 3K in the front, but with the Spyder diff there too. What tire are you running? and what type of track? Hard packed, loamy, what? These two things will have alot of effect on your car.

I dont race my rc's (just bash), but i do my full size cars

usually understear/overstear is most easly corrected with tire pressure and camber.

but had enough beat me to the camber recomendations. I also have an RPM gauge. youd be suprised how off you really are when you THINK you might have it close.

all the talk of diff oils is lost on me...I'd have much more faith in the geometry of the suspension and the smoothness of the driver before i spent the time to swap diff fluids around umteen times!

You can use the camber gauge to set your toe too. Just set the car straight up on the front wheels and set the gauge to the proper degree. I set my gauge at -1* to net 1* toe out on both the front wheels. Probably not the most accurate but it's worked for me.

Had enough is dead right about the toe, I didn't realise you were running toe in...should be toe out, that will fix the off power steering and give you a much better turn in...you also need some camber on the front, not too much though...man that bug's gonna feel better when you do just those two things...you need to look at some pro set up sheets for races on a similar surface to yours...I'll try and find you some...yes, when I say ARB, I mean the sway bars...try it without for a while, just to see, sometimes those things do more damage than good, and also, in 1:1 racing, rear ARBs are used to help prevent oversteer in front wheel drive cars...

Next time try it my way, it's very simple

Take a 2x4 and set it on the table on egde, then roll the car up to it, and then view the toe angle.

If you hold it in the air vertically with only the wheels touching the table, you're not setting the angle at the cars natural hide height. with the bump steer that angle will be different when you put weight on the wheels. You want to set the angles with the full weight of the car on the suspension

I never thought about that. I just ordered a PMB setup system so I should be good.

I only changed the toe on the front wheels from toe in to toe out and it was much improved.
Now i only have to free up the A-arms since they don't move freely enough and block the suspension.