Self Centering Steering | General Chat | GBS Owners Club
Avatar

Please consider registering
guest

sp_LogInOut Log In sp_Registration Register

Register | Lost password?
Advanced Search

— Forum Scope —




— Match —





— Forum Options —





Minimum search word length is 3 characters - maximum search word length is 84 characters

sp_Feed Topic RSS sp_TopicIcon
Self Centering Steering
April 29, 2018
1:06 pm
Avatar
peterb
Member
Members
Forum Posts: 3
Member Since:
January 6, 2017
sp_UserOfflineSmall Offline

Question for Simon please.

Hi Simon. Earlier this year, you posted some comments (copied in summary below) regarding steering self centreing checks at the IVA, and how some Mazdas try to turn into the lock rather than pull straight. I’ve noticed, during the very limited times I’ve driven my Zero, that I can’t seem to detect any self centreing. You mentioned that you have a trick that worked for you. Can you please advise what this trick comprised of? Many thanks. Peter.

“Nottingham did start checking that the vehicle would at least try to self centre if the steering was let go when in a turn. Mazda can have a tendency to turn into lock rather than pull straight, If you notice this on yours post, I have a trick that worked for me when encountered.”

April 30, 2018
1:14 pm
Avatar
Simon
GBS Technical
Admin
Forum Posts: 2283
Member Since:
August 9, 2013
sp_UserOfflineSmall Offline

This is a get around only, for the test situations.

Setting the camber to positive appears to reduce the tendency to turn in, I had one at +3 degrees once as does toeing the car in but it is trial and error.

I would start with setting the camber then adjust track. You do not need it to straighten fully, as your normal tin top does, just attempt to.

April 30, 2018
9:56 pm
Avatar
peterb
Member
Members
Forum Posts: 3
Member Since:
January 6, 2017
sp_UserOfflineSmall Offline

Hi Simon. Many thanks for the tips. Will give it a try come IVA time. Cheers. Peter

May 1, 2018
6:37 pm
Avatar
nelmo
Surrey
Member
Members
Forum Posts: 620
Member Since:
May 6, 2015
sp_UserOfflineSmall Offline

I had the same problem and just squeaked through the test. Afterwards, got a mate with one of those DIY laser sets to help me adjust it. Basically, I had set the toe-in by eye and it was miles out, even though it looked fine. 10 minutes with the simple kit and wheels were slightly toed-in and I had (and still have) loads of self-centering. Personally, I'd do it before IVA - you'll want to do it afterwards anyway.

May 1, 2018
8:12 pm
Avatar
Simon
GBS Technical
Admin
Forum Posts: 2283
Member Since:
August 9, 2013
sp_UserOfflineSmall Offline

Hi Nelmo, you have the Ford donor it does not have the Mazda thing.

they do not centre, to be honest its not to much of a problem when driving as the owner becomes aware of it and its liveable with in fact it helps with quick steering changes. needed for things like autotests, but the testers look for it and it does help straight line stability at speed.

May 1, 2018
8:29 pm
Avatar
nelmo
Surrey
Member
Members
Forum Posts: 620
Member Since:
May 6, 2015
sp_UserOfflineSmall Offline

Ah right...

May 2, 2018
10:40 am
Avatar
WallerZero
Coventry
Member
Members
Forum Posts: 94
Member Since:
May 11, 2015
sp_UserOfflineSmall Offline

So whats the difference between the Ford and Mazda kits that could cause this problem?

I had around 35psi in the tyres, about a -1deg Camber and (as it turned out later) around 2deg toe out. It wasn't great but the tester agreed it was trying to and passed it. I then forgot to reset the wheels (except pressure) and shredded the front tyres to slicks very quickly 😛

Mazda Zero 2.5L KLDE V6
Registered: March 2014.
Build Blog: http://zachsgbszero.blogspot.co.uk/

May 2, 2018
1:28 pm
Avatar
Simon
GBS Technical
Admin
Forum Posts: 2283
Member Since:
August 9, 2013
sp_UserOfflineSmall Offline

problem? Confused what problem? it's a characteristic Wink

May 2, 2018
2:07 pm
Avatar
NickMilbourn
Hampshire
Member
Members
Forum Posts: 326
Member Since:
October 27, 2014
sp_UserOfflineSmall Offline

This is a pretty simple explanation on how self centering happens...................... https://www.quora.com/What-causes-the-self-centering-effect-in-the-cars-Is-it-steering-axis-inclination-or-the-caster

So in short there's a difference in the Sierra and MX5 hubs causing less castor angle and/or the angle of the stub axle itself when they're connected on the end of the Zero's wishbones. A possible solution would be to have rose jointed front wishbones so you could force a change in geometry, but for the home builder this could be a dangerous level of adjustment if it's set up incorrectly!

1.8 VVT Mazda GT Zero - ATR throttle bodies & 171bhp!!
IVA passed Friday 21st October 2016!!
Registered April 2017

May 2, 2018
9:09 pm
Avatar
Simon
GBS Technical
Admin
Forum Posts: 2283
Member Since:
August 9, 2013
sp_UserOfflineSmall Offline

you could use the mazda adjustable camber eccentrics from the rear, now there is a thought, but agree with Nick it would need careful setting.

May 2, 2018
9:42 pm
Avatar
Marlin
Willits, California, USA
Member
Members
Forum Posts: 201
Member Since:
July 30, 2015
sp_UserOfflineSmall Offline

Simon, what camber and toe do you suggest for the rears since I have already installed the adjustable bush set?
Same as front perhaps (-1.0* camber, 1/16" toe-in) or less aggressive?

Zero GT Mazda(1.8LVVT) ordered Nov 9 '15, arrived Apr 15 '16,

May 2, 2018
10:26 pm
Avatar
Simon
GBS Technical
Admin
Forum Posts: 2283
Member Since:
August 9, 2013
sp_UserOfflineSmall Offline

I am a great believer in starting neutral and adjusting to suit your own way of driving. nearly 4 mm toe in is a bit aggressive, I would start parallel.

remember the rear is a parallelogram Cool

Forum Timezone: Europe/London

Most Users Ever Online: 96

Currently Online: tomwalker
6 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Members Birthdays
sp_BirthdayIcon
Today WallerZero
Upcoming None

Top Posters:

nelmo: 620

Mitch: 496

TOPCATNO6: 336

NickMilbourn: 326

Graterham: 208

RichardL: 206

michaelhopps: 202

Marlin: 201

Foxtrottransit: 201

2ofus: 169

Member Stats:

Guest Posters: 2

Members: 10239

Moderators: 0

Admins: 4

Forum Stats:

Groups: 2

Forums: 17

Topics: 1463

Posts: 9000

Newest Members:

DenpokEr, Grimgese, AchmedLope, RetoWora, Murakma, Rasuldult, GrobockWell, CharlesApawn, Ateraska, KayorSwep

Administrators: dijitul: 2, MidsZero: 314, Simon: 2283, Ruth Hall: 16