Possible rear wheel problem

[AMMO]

This is long and complicated but maybe someone can help.

 

I measured between the inside of the rear rims to the chassis and it appears that the right hand wheel is further from the chassis than the left hand one. I don't know if this is an accurate way to measure. I have 85 mm on the right and approx. 80 mm on the left. This is to the chassis tube that runs under the De Dion towards the fuel tank. This makes the De Dion offset by around 2.5 mm (if the chassis is accurate).

 

I've had the car 18 months and have never checked anything to do with the steering or tracking on the basis that the car used to go in a straight line at high speed with your hands off the steering wheel and the turn in was good. This was until recently when I added the extra triangulation to the forged top links at the front and the different but same diameter anti-roll bar. It has become a bit skittish and nervous. I put this down to the top wishbone perhaps changing the geometry slightly.

 

I am doing the tracking tomorrow with the aid of Steve Gilbert and some borrowed Dunlop gauges. By quickly checking with a long piece of 1" box section ali against the rear tyre I measured the distance between the box section and the front and rear of the front rim. The distance between the right hand front and the box section was in the region of 55/60 mm (front to rear of rim) whereas the left hand was only 25 / 30 mm (front to rear again). This would mean that I have stacks of toe out. The track is narrower at the front on my car and it also has 5 mm spacers behind the rear wheels so the 13" rims don't touch the De Dion tube.

 

I removed some toe out and it is better. Will do it acurately with the gauges tomorrow.

 

I realise that this is a quick and dirty method to use but it was enough to get me slightly perplexed.

 

My questions are (finally!): Is there any way to move the whole De Dion to the left to get it to centralise? I've heard of shimming the diff. Is this anything to do with it? Do I have to alter / shim / move the A-frame to centralise the De Dion tube? Is it possible to set the car up properly with gauges if the rear wheels are not equidistant form the centre line of the car?

 

Thanks for any advice. This is all new to me. Never had these problems with motorcycles!

 

 

 

AMMO

[Fred]

AMMO you can centralies the tube by washers inserted at the forward end of the a frame untill you get a acceptable tolerance of no more than 2 mm

 

you can also shim the diff it also is 2mm do you have a fax if so send me your no

 

 

fredid=blue> eek.gif

 

Edited by - fred on 25 May 2002 18:48:29

[AMMO]

Ta Fred

 

I'm plugging the fax in now. 01394 383499.

 

AMMO

[STEVE GILBERT]

And best of all I have been here and done this, so we can look at it tomorrow! I am now an expert with the Dunlop Guages and have set the tracking on every car that has ventured near my house!plus re done the seven 3 times(to perfect the steering wheel) and checked the rears. A new toy to play with, what fun. Also I have some spare washers and bolts for the rear suspension if needed. See you tomorrow

Steve 80)

[Fred]

fax sent good luck

 

fredid=blue> eek.gif

[AMMO]

Fred

 

Fax cam through nice and clear. Thanks for that.

 

AMMO

[AMMO]

Rear wheels now equidistant from chassis. Thanks to fax from Fred and help from Steve Gilbert and some shims. Was very easy to do, took only around 15 minutes.

 

Drive home on damp/wet roads was good. Spinning up rear wheels around roundabouts and in a straight line is completely controllable. Before felt like the back end was alway trying to step out. Set the front toe to 0. Will experiment with toe-in and toe-out over the next few days.

 

AMMO