Lancia Motor Club

Can anyone help with this query please?

Hello , I act as curator of the home fleet of lambda owner/member Douglas Blain.

He also owns a  unique trials special known as the Crocus built in 1950. It comprises an HRG chassis , Ex HRG Singer 1500cc engine ,Pre select g/box,Triumph Dolomite rear end, and a 1938 Aprilia steering/suspension system. We seek basic toe in /out settings for a standard Aprilia to start as a basis to  sort this renovation’s  wayward steering habits. Can any one assist please ? A third Lancia in the fleet , a Thema 832 What a motor car!

Regards Keith Styles

P

Hi Frank,
Search 'Maintaining an Aprilia' on this forum. It gives photocopies of the excellent booklet that was produced by the LMC back in the Eighties, which has some of the suspension settings.
 
Regards,
Tim

From memory, toe-out is about 3-5mm.

Hi,

I have just replaced all the steering bushes, and am now planning to set the steering up with 0 mm toe in as advised in the Aprilia maintenance note for radials.  But have hit a snag (as always on Aprilias!)   On the attached diagram from the TAV there are three adjustment points...one on each end of the main steering rod marked in the diagram as 7 and 10 , and then a further adjustment cam on the steering rod attached to the drop link from the steering box - marked 11.  Looking at the setup i can see how 7 and 10 adjust the toe in...what does 11 do?  Is there a sequence to be followed in setting the steering angles?  I have also realized that the adjustment pins for 7 are broken and will have to be drilled out...which means taking off the bracket marked 8 from the sling pillar - which means taking off the brake drum, brake shoes and backing plate...or can i ignore one end and adjust angles all on the 10 and 11?

many thanks for the help,

David

 

I'm not an expert on Aprilias but looking at the diagram my guess is that adjusting at point 11 which connects the drag link to the arm on the steering box is to enable the steering wheel to be set straight ahead when  the wheels are  straight ahead.

I think you should first set the toe in on the track rod, if there is enough adjustment available at one side you can just use that and ignore the other end unless you find that the track rod is then noticeably out of parallel with the axle beam, in which case you'll probably have to sort out the broken pins so you can adjust both ends. Finally when you can drive the car, adjust the drag link at point 11 if the steering wheel is not central when running straight.

Just my thoughts! If I'm wrong perhaps some Aprilia chap can correct me.

Mike  Clark

Morning Mike,

That makes sense, thank you.  I managed to free up the broken adjustment pins at the problem end and remove them this morning - a major success...so no need to take the hub off to get at the bracket now -  :)  so have just painted parts that were rusty and now need to wait for them to dry before reassembling and setting the toe angles...will be interesting to see if the new silent blocks solve the low speed steering wobble i had that caused me to replace them all...

Many thanks
David.

You will notice an enormous improvement in the steering if you replace those miserable rubber bushes with proper ball joints, as detailed in my thread on Track rod ends.    Not original I know but I always am prepared to do little modern modifications to improve safety and handling.

Hi David,

interesting suggestion, and am tempted...but have hit much bigger issues.  I fitted all new rubber bushes and put the steering back together.  I had also noticed that the steering arms were bent, so i straightened them before reassembling everything...on moving the steering through its full range whilst stationary to check the steering stops,  the steering rods bent again...on closer inspection i realised that the main rod that connects the two wheels was very corroded at each end and was bending as a result...basically the rod had had it and was likely to shear at any moment!  I now need to source some new steel tube, cut off the bush housings at each end and weld them onto the new tube.  Typical of life getting the Aprilia back on the road!...one small step forward with a test drive and now two large steps backwards!

cheers
David.

An even better reason to fit proper ball joint ends rather than trying to weld back those bush housings.    Whilst you are making new rods why not do it properly?

Hi David,

it is tempting to fit rose joints, but i don't think i am confident enough to do that to the Aprilia yet...when i have had it on the road for a while  i may then consider going down that route.....

https://www.lancia.myzen.co.uk/forum/index.php?topic=10912.0   tells you how to do it.

Having ended up with the last of Ben Courage’s used Aprilia parts I noticed a few of the steering rods/ties are slightly bent, including the one on my project car, one even had wooden blocks jubilee clipped to it. I can only assume this is a way to shorten the tie to give more toe-in than the concentric pins allow, a novel way of recalibrating the set-up.         
I am definitely going the ball/rod-end joint way. 

I suspect that one came from the treed car!    The original rods are a bit feeble and bend quite easily so it may just be damage from parking on a tree stump!

Completed the new steering rod yesterday (with help from a friend on the welding!)...i put a thread on one end so that the length was adjustable and used thicker section tubing to hopefully avoid any further issues. Now need to paint it and then fit!

Further update on my steering.  I have now replaced all the steering bushes and fitted my newly made track rod, and this lunchtime (before the big storm is forecast to hit) took the Aprilia for another short test drive.  I still got the very nasty wheel wobble from my right front wheel at around 10mph...so headed home straight away as it really does feel like the wheels about to drop off...after replacing all the bushes and finding the problem still remains i now am suspecting its the sliding pillar at fault. I also get a nasty "clonk" from the front from time to time going over bumps and the car does feel like its "floating" very slightly too...plus on applying the brakes (just fitted with new seals all around) i get a slight pull to the right (and sometimes the left)...any views welcome!

Are the wheels properly (dynamically) balanced?

Regards  Karl

I agree about the wheel balancing , they are very sensitive. Badly balanced wheels can give a "funny vagueness" at the steering wheel, but as Karl suggests, it isn't just the wheel itself, you need to consider the wheel/drum combined - is it better or worse if you refit the wheel at 90° or 180° on the drum ?

The brakes do tend to pull a little on light application especially if you have fitted new linings as well.    It is not anything to worry about.   The wheel wobble at only 10mph does sound much more like pillar wear than balance which only tends to come on over 40mph.   It is difficult to test the pillars for slack as if you jack the car up to free the wheel the pillar is then at the very (unworn) end of its travel - I used to get my Lambda through its MOT using this trick.   Try heaving on the top of the wheel when the car is sitting normally.

Thanks for the comments... i will move the wheels round through 90 degrees to check, but suspect that's not the issue as the tyres are new and the wheels are recently balanced and its occurring at a low speed.  I think it may be the sliding pillar and in particular suspect the bearing that allows the pillar to rotate...will try another test drive now the weather has cleared...