G'day,

I've noticed an issue with Minnie where both back tyres are scrubbing on the inside tread. I haven't noticed it before today when I was greasing the radius arms. There is no sign of scrubbing on the front tyres at all. I last greased the arms about 2,000 mile ago and didn't notice any scrubbing, however it may have been there but not as noticeable as now.

Minnie is a 1963 850 with cone suspension and hi-los on front and rear. Suspension was fully rebuilt about 5,000 mile ago (including new bushes, bearings and pins in the radius arms) and had a wheel alignment at a Mini specialist. At that time, they said the rear was in spec and just needed a tweak at the front after I'd done a manual alignment using string when I put everything back on the car. There is no movement at all in the radius arms. When I first got the car on the road, I did have issues with the rear end toe in/out and I asked about that on here and following your suggestions, did seem to get things right given that when it was aligned professionally, the rear was ok.

Minnie sits really good on the road and doesn't wander about.

Where should I start looking for what's wrong? I'm thinking the culprit could be too much negative camber but thought I'd ask you blokes first before going off half cocked and getting things wrong. Might be too much toe out on both - and if that's the case, shims won't address that problem as far as I know.

If it is a case of needing camber adjustment, I see Minispares (and Minisport) sell a basic kit MS70 and an upmarket kit MS73EVO. From what I've read about these kits, the MS70 kit will address camber only whereas the MS73EVO will do camber as well as toe in/out. Has anyone used either of these and which kit would you suggest be best. I prefer doing the job once and right so a few $ difference in price is ok. From my old post, I know some of you blokes have the adjustable kits and I'd like to know which one to get (if I need one).

On the bright side, I've been thinking about putting a set of Minilites on to replace the standard rims and hub caps and have been waiting till the tyres wear down. Might be good opportunity to convince Bullwinkle that I need a whole new set to fix the problem

Thanks Rocky.

If you don't have adjustable or modified brackets then it's unlikely to be the camber. The factory camber is too far positive for radial tyres.

How was the rear toe last measured? Are any shims already installed? I've read of people running a string line along the side without thinking about how the track width is different.

If you do need to modify the rear camber then the "best" way probably is to actually file the original brackets. There are many complaints of the adjustable brackets not fitting or even breaking.

Edit: Looking at your old posts I think you will have too much toe out. Your thrust angle is likely way off so it will be crabbing too. If you can try to get some current measurements it would be great.

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1986 Mayfair (998 auto), 1974 S, 1974 Van, 1972 PMG Van

Too many minis

I use the method on this web page - parallel strings - follow the instructions and you'll see where it's at... https://robrobinette.com/DIYAlignmentCalculator.htm

Ordinarily you'd say rear toe out, but if it doesn't wander about you wouldn't think so - I have a silly amount of rear toe-out, with a little bit of camber - the car is quite (very) skittish, but doesn't scrub the inside edge of the tyres

Maybe you drive on straight roads too much?

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did I tell you that I won a trophy?

Thanks for the info 68 auto and Simon.

I did make up a modified bracket to use if needed when the initial alignment was done. At the time, the said they didn't need it as everything was ok with the non modified bracket. Seeing as I took it to a mini mechanic, I just assumed all was good.

I've also learnt something new - thrust angle. Minnie may well be crabbing a bit but it does sit on the road quite nice and corners ok. Mind you, it's only an 850 on standard rims and tyres so not a hoon car but my eldest son does tend to push it pretty hard and it seems ok.

Majority of the road I go on are country ones and apart from a few curves, pretty much straight. Would be more fun on lots of nice twisty roads but none around here unfortunately.

Simon - that calculator you've linked is the one I used when I was setting things up. You put me onto it back then and I found it real easy to do.

I'll have another go measuring things up on Tuesday when I have a spare day and see what I can find out.

I have a question about setting up the string line though. For the life of me I can't remember exactly how I did it last time and I didn't take any pics as a reminder.

When setting up the string lines, do I make them parallel to the sills on each side as well as making sure the strings are parallel to each other? The model says the strings do not need to be parallel to the car as it will work things out but just want to check how you blokes do it please.

Also, does anyone now of a real good alignment joint in Western Vic I could go to? Some I have contacted can't handle 10" wheels.

Thanks Rocky

The important part is that the strings are parallel to each other. Alignments usually don't reference the body at all so I'd do them equal distance to the hubs, not the body. I effectively use the hubs but I'm not using string.

The only measurements I do against the body is the suspension height.

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1986 Mayfair (998 auto), 1974 S, 1974 Van, 1972 PMG Van

Too many minis

I do it as-per that website, I don't make any more than a very vague "more-or-less-ish" attempt to make the strings aligned with the car - often when I do it, I'll be measuring ~70mm from the string to the rear wheel on one side, and ~30mm on the other, similar variation but opposite sides at the front - IE the car is noticeably rotated inside the rectangle made up by the strings. I actually use one long bit of string, with an axle stand on each corner. I align the strings (by eye) across the front and rear of the car, but down the sides? nup, I don't bother, so long as the strings are parallel, and don't touch the tyres.

I had a VW Polo GTI for a few years, I was doing sprints at Winton with it, along with using it as a daily. They have a torsion beam rear-end that is not adjustable in any way - factory is a little bit of toe-in and zero camber. I wanted a little bit of toe out so used that websites method to calculate the exact amount of change I wanted on each side and had some flat aluminium plates laser cut, then set them up in my lathe to face them off at the slightest angle to correct the toe, and give a little bit of camber. When I was done, it measured up where I wanted it. I took it for a proper measure at the aligners and it was spot on. It was a fun car, I made it handle like a mini

_________________
did I tell you that I won a trophy?

Keep in mind that the track is different front to rear. If you set the string lines the same distance to the hubs all around the car they WON'T be parallel.

I had a couple of lengths of timber (longer than my widest car) and set them up on axle stands across each end of the car. I'd notched and labelled the "sticks" at different widths to suit each car.
With the strings set in their corresponding notches and running down each side of the car, I'd slide each stick left to right to get the distance to the hub the same on each side.
As I said earlier this left-to-right string-to-hub distance is different at the front than at the rear (closer at front on the mini - ie wider track).

Unfortunately I had a seniors moment and threw them out during a shed tidy-up . I'll have to make up some more........

I filed the rear brackets and have always run 1/2 a degree negative camber on the rear. Tyre wear is perfect across the tread.

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Cheers,
Rod.
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'63 Morris 850 (Old Secondhand CAR)

Maybe a few pictures would help some us (me) understand their setups as our imaginations are not understanding a physical setup.

This is important. I mean exactly as you say. Doing it this method means the values you then measure at each wheel should be equal side to side. When checking the alignment of each wheel you can then just calculate it directly from the measurements at that wheel.

The hardest part about doing alignments is understanding exactly what you are measuring and how you are measuring it no matter what equipment you are using. Make sure you understand exactly what you are doing before attempting to measure. If you don't understand what you are doing then you won't get a satisfactory result even with the latest machines - it's down to the operator, not the tools. Be prepared to spend all day doing a proper alignment with string.

An alignment with string can be done better than the result of most alignment places with the fanciest equipment but the fancy equipment can be more accurate in the right hands.

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1986 Mayfair (998 auto), 1974 S, 1974 Van, 1972 PMG Van

Too many minis

This article (the first that came up) is mostly good but doesn't make it clear enough that the strings need to be parallel. It should give you an understanding though.
http://speed.academy/diy-wheel-alignment-how-to-guide-explained/2/

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1986 Mayfair (998 auto), 1974 S, 1974 Van, 1972 PMG Van

Too many minis

That's exactly my setup, only I'd used lengths of timber I had lying around at the time.

Getting the lines parallel is no problem with this method.

As an example, say you have the string ends 2.2m apart on the front stick, then you make the distance between the string ends on the rear stick exactly the same at 2.2m.

Then, with the strings running down each side of the car, you slide the sticks back and forth in the stands to set the lines the same distance from the hubs left-to-right (remembering the front will differ from the rear) and there you have it - parallel lines with the car sitting dead square inside them.

Yes it does take time to do, but the rewards are there for the taking.

I got 25,000km per set on my first 2 sets of tyres on my Mazda RX8 (bought new). An alignment was done at the shop at each tyre change, but after the second set wore out I decided to check the alignment myself after the 3rd set was fitted by the shop.

What I found was that, yes the corners were all in spec, but the tolerances meant there were slight differences between sides.

I set everything up with the good old strings and a caster/camber gauge precisely to where I wanted them, with no tolerances, and the improvement to an already great handling car was astounding.

That third set was replaced earlier this year because they got too old. They were only half worn, dead even across the tread, and had done 23,000km - only 2,000 short of where the others had worn out!!! I don't granny drive the car either.


Another thing to keep in mind is that if you're playing with castor/camber the car MUST be level.

I have a long dead-straight tube and put it across the floor with a level on it and put packers where each tyre will be.

The amount I have to insert under the tyres to get things level in either of my sheds is startling

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Cheers,
Rod.
______________________________
'63 Morris 850 (Old Secondhand CAR)

my problem with using pieces of wood or pipes that are the right length is that I'll go looking for something that size, only be able to find those, then cut them up......

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did I tell you that I won a trophy?

Well I had a chance today to set up the strings lines and measure things up.

I took a heap of pics while I was setting it up and will post these, together with a few words about how I went about it, so others can see how I did it and for those in the know, to make sure I did it right.

I've attached a pic of the calculations from the model that Simon posted so you can see the end results.

For the front end, I have 0.41 degrees toe out and the passenger side and 0.62 degrees toe in on the driver side. I'm thinking that I didn't have the wheels exactly dead straight seeing as one side is out and the other in. Going on these numbers, it looks like I have a whisker of toe in of 0.21 degrees. No noticeable tyre wear on the front tyres.

The rear tells a different story with both sides showing toe out - passenger side 0.62 degrees and driver 0.82 degrees giving a total of 1.44 degrees toe out.

In my mind, I'm picturing the rear wheels splayed out slightly and thus resulting in the wear on the inside of both rears. Is this right? Given both have toe out, is this why Minnie still drives ok given toe out is a no-no I believe on the rear?

The other calculation that shows is the thrust angle (which I'd never heard of before it was raised in the thread) and it shows -0.10. What does this mean on my car please? Is that a result of the toe out on both sides or is the subframe crooked in the car? Is the amount significant and if so, how do I fix it?

For the toe out fix, I understand that I'll need to either file out the holes in the end of the bracket and weld a new washer in place or buy a set of adjustable brackets. For the amount of toe I have, roughly how much would I need to slot the existing holes by? I'm thinking it would be trial and error and possibly a case of slotting the hole by more than required and then shim out as shims are easier to muck around with rather than trying to get the right amount of adjustment by slotting and welding washers in place.

Perhaps a set of the MS73EVO brackets would be easier for me to install as I could adjust as required while they are on the car. I did see a mob called Voodoo racing aust make a set of pretty smick ones for racing but at $550 a set they are over the top for a 850 run about I think.

I should be able to post the pics etc later tonight or tomorrow.

Edit - An update on this after I had a good look at the radius arm where it bolts onto the subframe. I do have a spacer in the drivers side bracket (thought I did but wasn't sure) so I'll pull that out tomorrow and do the measurements again. I also reckon that the bracket I modified for the passenger side was to address the toe out I thought I had when I was putting everything back together. I did take it to the mini specialist but he said it wasn't needed. All I have to do now is find it. Tidied up the shed recently and now I can't find anything. When it was a mess, I knew where everything was.

Thanks Rocky

That thrust angle is acceptable but it will change when you fix the toe, it is basically the difference in toe compared to the centreline of the front wheels. It can also be compensated for to straighten the steering wheel by adjusting the front toe but ignore that for now.

Toe out on the front should be a total of 14 minutes (60 minutes to a degree). Toe in on the rear should be about 30 minutes.

As for the front wheels being unequal, centre the rack and steering wheel. Lock the steering wheel in that position. Adjust so the toe is equal. If you don't do this then the geometry gets messed up.

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1986 Mayfair (998 auto), 1974 S, 1974 Van, 1972 PMG Van

Too many minis

Don't you love it when everyone uses a different measuring system!

Millimetres, decimal degrees, degrees in minutes and seconds....

I confess that I don't actually use the website, I have a CAD model that I put the numbers in to and it gives them to me in millimetres. I keep telling myself to put the calculations into an app - it's on my list of "good ideas to do one day"

I put your numbers in there and yes, you do have 7mm of toe out at the back, which for a road car, is a lot, like HUGE - I run 10mm on my car (remember I said it was silly)

You have 1mm of toe in at the front, if I was you, I'd just undo the lock nuts on the steering tie rods and screw them both IN half a turn, then lock them up and leave it - or ignore it as 68+86 says



When I started reading your post I was going to ask if there were shims in it - the shim on that side is there to take up a heap of toe-in that was on that side, or more likely, even up that side with the other side.. similarly, my car had shims in one side but not the other, I suspect because of a hit in the rear on that side, shortening the wheelbase a bit (I think there's something like 10mm difference in the wheelbase before my adjustments).

Keith/Voodoo is a friend of mine, he made those brackets after we talked through the limitations with my brackets, and the brackets that were on his car. He gave me a set, but I haven't fitted them yet (they're on the same list as above). They are overkill for what you want to do.

I have the minisport MSLMS0510 rear brackets, I don't like the minispares MS73EVO because they only have 3 toe positions, I want more adjustability than that. If I was you, I'd file out a set of standard brackets, get them right, then weld washers to them

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did I tell you that I won a trophy?