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MOT PASS BUT
jacko - 13/4/04 at 08:49 PM


hi all
been for mot today and passed brill. but on the way there it would not self centre on the steering. any suggestions on how to correct this? do the wheels need adjusting to tow out or in? and by how much. Thanks for advice hopefully Jacko


jacko - 14/4/04 at 07:36 PM

THANKS SNOOPY
My sva is on monday i will try your suggestion
jacko


britishtrident - 14/4/04 at 09:06 PM

What tyre pressure are you running --- the front wheels only carry about 1/3 the load they would on a Sierra or Cortina the tyre walls need to distort to allow the tread to generate self-aligning torque.

Corect tyre pressure varies accorrding to size and engine weight start with 16 psi and experiment up and down by a few psi.

Using toe-out will cause steering instability especially under braking..

[Edited on 14/4/04 by britishtrident]


NS Dev - 15/4/04 at 08:04 PM

lack of self centring is due to lack of caster angle, altering the toe is just a bodge around this problem. Is there any "spare" room in your upper or lower wishbones brackets which is packed with washers? If so, put all the washers in front of the bushes at the top and behind the bushes at the bottom, this will have the effect of increasing the caster angle a bit (though I doubt enough to make much difference)

The correct way to do it (and I know it is a bit late now!!) is to make the brackets substantially (8-10mm) wider than the bush inner tubes for the front wishbones, then you have loads of room for adjustment and if you think washers are a bodge then you can use these to set it all up right then turn up some spacers once you know the correct packing thickness. This is how I made the front suspension on my specials in the past and on my racers so I can adjust the caster easily but still use bushes rather than rose-joints.


britishtrident - 18/4/04 at 09:47 AM

One way to alter the "U" brackets to make them wider is simply cut one leg off and grind the end to nice smooth shape, then make a suitable "L" bracket to replace the leg removed.

Don't be tempted to use "bedstead angle" for the "L" bracket it needs to be plain mild steel.