Turns left faster than right - Mini-ZRacer.com Forums

bbeattie · 2004.06.11, 09:14 PM

My 02 MM enzo wants to turn much faster to the left than right. It may be better though to say it spins out more to the left than right. I can control the left spin outs pretty well, so I don't flip all the way around. Right turns at high speed though make for very, very wide turns. It's probably safe to say turning left understeers, turning right oversteers. I'm running a kyosho diff. If it's loose, or tight it seems to be the same. The only exception is if it is loose enough, the car doesn't spin out, so both right and left turns are about the same, but lefts are still slightly sharper.

Is this normal? Should the diff be set tight, loose, in the middle?

The difference at a fairly good speed is about a 3foot radius vs a 7 foot radius.

I'm running 8 degree GPM V groove, the front tires though are totalled after just 2 hours of testing and trying different configs (The tires got hot and melted so they're quite bumpy and the V-groove tread is barely noticable only in some spots). Running 15db, 30dg, and 55dg tires still give the same behaviour, but the harder the tire the difference isn't as much.

If this is normal, do most people prefer to leave a lose diff so stearing radius is about the same left vs right, or tight so you turn left a lot faster than right?

--Brandon

acyf · 2004.06.11, 10:26 PM

Check on the H-Plate to see the alignment is in the centre, that means the mount did not shift to left or right.

Or may be your tire is hit the body when turning.

TNB · 2004.06.11, 10:46 PM

I go through a set of 20s in about 1 hour of "hard" run time on an RCP track--changing to fresh batteries every 15 minutes. During that time I also need to swap the front tires or change running directions since the right front tire tends to wear more than the other side. I can also tell when the tire is wearing because the car will pull to one side. I'll also end up increasing the dual rate as the tires wear. If I use 30Fs, I can get some extra track time in on a set--harder tire.

Aaronnn · 2004.06.22, 03:32 PM

Quote:

Originally Posted by bbeattie

Is this normal? Should the diff be set tight, loose, in the middle?

--Brandon

Basically,
your diff should be set according to spinout....never to loose or damage will acure..if you have great traction and have no spin outs...set diff at a lock position....spinning out ? then loosen up...

i think you have other issues other than diff settings....maybe suspension or tire rub....

Aaronnn · 2004.06.22, 03:37 PM

Quote:

Originally Posted by bbeattie

The difference at a fairly good speed is about a 3foot radius vs a 7 foot radius.

--Brandon

i am guessing front suspension problem or king pin/knuckle lock-up....

bbeattie · 2004.06.23, 12:56 PM

Quote:

Originally Posted by Aaronnn

Basically,
your diff should be set according to spinout....never to loose or damage will acure..if you have great traction and have no spin outs...set diff at a lock position....spinning out ? then loosen up...

i think you have other issues other than diff settings....maybe suspension or tire rub....

What type of damage can occur? Just curious, I've toyed with it quite a bit. I am looking at getting a new diff as I bent the axel on my kyosho ball bearing. :-) It was clocked at 32MPH (Xspeed and 12 tooth gpm pinion gear) shortly seconds before I hit the break to slow down, it spun out and caught the right tire on a 2x4 in the warehouse. (But the carbon fiber h-plate and gpm sliding rear motor pod are 100% good still) Straightening the diff didn't fix it well enough. There's still too much wheel hop at high speed even with a near straighened axel.

Any comments on the GPM ball diff? does 12 ball bearings really make it smoother?

--Brandon

Aaronnn · 2004.06.23, 05:29 PM

if your diff is too loose...it can get too hot....i have never seen one damaged...but i imagine it can warp or melt the spur...maybe the rings..or balls...
give it a try and let me know what happens.....

p.s. i was thinking also...that you will need to verify that your servo assembly is working correctly...i.e. turns both ways at the same rate.....no binding, etc....

Aaronnn · 2004.06.23, 05:31 PM

Quote:

Originally Posted by bbeattie

Any comments on the GPM ball diff? does 12 ball bearings really make it smoother?

--Brandon

no comment.....

p.s.s. stop hitting 2x4's would ya!!!

bENZinO · 2004.07.07, 09:32 PM

Quote:

Originally Posted by Aaronnn

p.s. i was thinking also...that you will need to verify that your servo assembly is working correctly...i.e. turns both ways at the same rate.....no binding, etc....

i too have the 02 ENZO and have niticed the same, aaronnn sounds like hes got it because when i look at my wheels/tires from the bottom, its almost like theres a small range of turn where it doesnt steer, the as you keep turning (SLOWLY!) you'll see the wheels/tires jump a little to the left to get to where you have turned to.
i hope that makes sense. i'll check back and let u know if i can correct (will ask local "club" members tomorrow) and if youve figured it out, let me know how u did it.

-thanks and happy motoring

bbeattie · 2005.06.20, 01:42 PM

You're not going to believe this, but I've found the problem. After over a year and countless hours of tweaking, it turns out it is the body. I changed bodies of my car with a "less damaged" red enzo (Identical). The spinouts vanished. I put my body back on, they came back, tried other bodies, the problem went away. I know this sounds a little out there, but it's true. If anyone else is having major spinout problems, and the car wants to turn left faster than right, try another body... :-/

bbeattie · 2005.06.20, 01:44 PM

Quote:

Originally Posted by bbeattie

You're not going to believe this, but I've found the problem. After over a year and countless hours of tweaking, it turns out it is the body. I changed bodies of my car with a "less damaged" red enzo (Identical). The spinouts vanished. I put my body back on, they came back, tried other bodies, the problem went away. I know this sounds a little out there, but it's true. If anyone else is having major spinout problems, and the car wants to turn left faster than right, try another body... :-/

I should note, I tried different bearings, tried stock diff, changed pinions, front springs, rear spring tension.. nothing helped get rid of the spinouts except the body change.

ruf · 2005.06.20, 04:16 PM

Adjust the rear tweak. Very few h-plates are actually perfectly straight. Hold the car with both hands with the rear facing you. Push the left tire with your thumb and then the right tire. Go back and forth. You will see the rear suspension "recover". If it recovers down more to one side than the other, put a thin shim inbetween the h-plate and the motor mount on that side where the mounting screw goes. This will space the motor mount up on that side and SHOULD balance the car. I use the 0.3mm Kyosho shims. Just make sure it's ultra thin or it will tweak the car the other way.

Also make sure that nothing is binding or rubbing on the body like tires, motor wires, etc.

bbeattie · 2005.06.20, 05:25 PM

Quote:

Originally Posted by ruf

Adjust the rear tweak. Very few h-plates are actually perfectly straight. Hold the car with both hands with the rear facing you. Push the left tire with your thumb and then the right tire. Go back and forth. You will see the rear suspension "recover". If it recovers down more to one side than the other, put a thin shim inbetween the h-plate and the motor mount on that side where the mounting screw goes. This will space the motor mount up on that side and SHOULD balance the car. I use the 0.3mm Kyosho shims. Just make sure it's ultra thin or it will tweak the car the other way.

Also make sure that nothing is binding or rubbing on the body like tires, motor wires, etc.

Trust me, I've checked that many times.. this post was also stated elsewhere if I remember correctly..

Also, the bodies never touch the rear wheels or anything else (or never should atleast), and although this could be a problem, it wasn't for me.

davkin · 2005.06.21, 07:34 PM

Brandon,

Check the body and see if it's tweaked, especially the very front where the front clip goes in. I'm thinking it may be possible that a tweaked body could tweak the chassis when mounted.

David

Pippoe · 2005.06.22, 11:47 AM

Quote:

Originally Posted by Aaronnn

if your diff is too loose...it can get too hot....i have never seen one damaged...but i imagine it can warp or melt the spur...maybe the rings..or balls...

Ahm.. if you keep the differential at a too loose setting (that is, if the diff can slip quite a lot) you'll simply wear out the metal balls contained inside very quickly. If the balls get more and more out of shape (due to wear), the dif will become uneffective..

...concerning different turning radiuses: Isn't that normal? How does the car behave on acceleration? Will it go straight or will it drift to one side?
The force introduced to the rear axle by the motor isn't simmetrical (because it's introduced at the right side wheel), therefore -depending on the engine you use- you will notice a more or less strong momentum when steering under load (or accelerating heavily).. you can eliminate most of the momentum with diff setting and traction (good tires) but imho you can't get rid of the problem.

Cheers

Pippoe