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Ackerman problem?
dream - 12/1/13 at 03:19 PM

Does the avon really have problems with the steering rack placement?cheers

snakebelly - 12/1/13 at 03:52 PM

Are you referring to bump steer, depending on your setup it can be an issue but until the front end is built up and all settled it may be difficult to define, things like ride height and wheel size can contribute . Rob has just had a nifty mod done by Mac#1 to get rid of his, I'm sure he will be along shortly with pics
Hth

snapper - 12/1/13 at 04:11 PM

Ackerman is a line drawn from the track rod end through the hub pivot point to the center of the rear axle
Bump steer is a different issue

snakebelly - 12/1/13 at 04:36 PM

Yes but as far as I'm aware the Avon doesn't have an Ackerman issue but can have a bump steer issue, hence me asking for clarification

dream - 12/1/13 at 05:28 PM

i mean the inner wheel in a corner goes through a tighter circle,

JoelP - 12/1/13 at 05:40 PM

quote:
Originally posted by dream
i mean the inner wheel in a corner goes through a tighter circle,


That would indeed be ackerman rather than bump steer then. Since you are using hubs off a donor, all you can change is the position fore/aft of the steering rack. Have a read up (via google) about ackerman and rack position, and compare to where yours will be.

britishtrident - 12/1/13 at 07:04 PM

Any picture I have seen of Avon front geometry show it has toe-in in turns.

Basically set the front wheels in the straight ahead position and looking down from above imagine a line joining the centres of the track end ball joints.
If the steering rack lies behind this line you have at least partial toe out in turns -- which in effect gives you some ackerman.
If the steering rack lies ahead of the imaginary line your car has toe-in in turns -- which is not good as it gives poor turn in and front end grip.

jossey - 12/1/13 at 07:38 PM

As mac has said from my research n calculations its just bump steer but this can be solved with rose jointed rack ends. See laptoprobs pics.

I shouldnt have the issues due to my bike engine setup being lighter on the front but we will see. I have the wider wishbones as the ther real issue with the aim is the under steer due to the narrow front end.


Thanks

laptoprob - 13/1/13 at 08:43 AM

quote:
Originally posted by jossey
As mac has said from my research n calculations its just bump steer but this can be solved with rose jointed rack ends. See laptoprobs pics.



Rudy - 9/2/13 at 08:52 AM

please read this http://www.locostbuilders.co.uk/viewthread.php?tid=116631