Hi members.

With my ea81 conversion completed and running very well, my next step is tyres. Since I've had this triek from new it has chewed up the inside of the tyres mainly on the near side (LHS).

This trike has airbag suspension and Munroe GT shockers. Recommended airbag pressure is around 50psi. However I can pump in 70psi and the nearside wheel is still at a inside wear angle.

Rubs out tyres quite quickly.

Wondering if the old IRS has worn bushes but am unfamiliar with the design. Any advice thanked in advance.

pic doesnt show it up much

Yes,

You have outer and inner torsion bar bushes on both sides
plus inner suspension pivot bushes up near the gearbox..

all these probably need replacing..

check out: http://www.vw-resource.com 

on how to replace these...

also.. You can adjust the toe in - toe out on the rear suspension.. maybe one side is out??

may need a rear wheel alignment...

cheers

LEE

Thanks Lee. that was quick!!


Anyone know of a good rear wheel aligner in Northern Melbourne area? Or anywhere in Melbourne or Northern Victoria?

My Son had problems with a beetle with IRS rear end

the alignment was out....

You notice it more with Big wide tyres..

LEE

The reason why the rear ends of Beetles, both swing axle and IRS have notches cut into the spring plates and the rear axle assemblies that they bolt to, is so that they can be replaced with the correct amount of toe in, which is set by the factory.

If you start to pull a rear end apart and there are no marks at the ends of the spring plates and on the rear axle assemblies, use a big cold chissel or an angle grinder to put them there.

The rear end must have some toe in or the tyres will wear badly.

When you solve this problem and if there are no marks in correct places, put them there, and make sure that in the future you re-align the marks upon re-assembly.

The problem with fitting spring plates and axle assemblies together that were not originally matched in the factory, is that the marks cannot be trusted.

I usually set the axle assemblies in the middle position in that case. So far it has worked O.K.

yea, check the bushes for wear and then get the rear aligned. Pedders are best but a few of the tyre companies are OK. Wouldn't trust Beaurepaires or Jaxx.

thanks guys.

Today I got Volksplace in Melbourne to look at my rear suspension.

Rob took both wheels off and both wheel bearings were loose. and the worse wheel for camber had a loose backing plate behind the knock on/off wheels.

So it straightened the wheels out almost vertical. So now I will take it to Pedders (where I recently has new airbags fitted to the IRS) for a wheel alignment.

great advice fellas.

I had an issue where after everything was replaced and levelled up I still had uneven camber. There is a limited amount of adjustment there but you need someone who knows what there doing.

I've found out the Panther trike has its own fabricated chassis and swing arm mounting design. And it isnt adjustable.

So at Pedders they ascertained that to straighten the wheels you'd have to pump up the airbags to 100psi!!! but that gave me something to go on.


Since owning my panther my 'BOSS' airbags have always gone down slowly. My rear tyres also suffered from excess inside wear. I decided to do someting about these two issues particularly now that I've decided to replace the tyres with a good quality brand.

The first step was to replace the airbags with better quality. The BOSS airbags are assembled with top and bottom plates where the airbag is snadwiched together. Lose one bolt or general wear and tear can cause leaks easily it seems.

Searching around I located replacable airbags by Pedders that are a common size and also used on Landcruisers and other vehicles.

One difference was that they are 10mm shorter in length. Meaning they will add to the negative camber not reduce it.

This is one tyre with inside wear.





There is one remedy to the negative camber and that is to pump up the airbag much higher. But that would make our bones rattle.

I then got Volksplace to check the swing arm bushes. They also tightened up the wheel bearings. The buskes were in fine shape.

I returned to Pedders to accurately measure the airbag pressure required to enable the rear wheels to be vertical- or within 1 degree.

The results were surprising. There was 2.5 degrees negative camber and tow out was excessive. When the airbags were pumped up to 100 PSI the toe out vanished and the camber went down to an acceptable 0.5 degrees.

To remedy this situation they suggested getting a spacer made of 30mm thickness to place between the bottom of the airbag and the arm base.

I visited my friend steve (the engineer that built my roof in Euroa) and he had just the material. Industrial plastic at 115mm diameter (perfect) in a cylinder shape. So he cut off 30mm and drill an 8mm hole in the middle for the airbag bolt.

I purchased two longer bolts and fitted the spacers.

The spacers



In place




Much better.



The spacer thickness was critical so I'd advise those with this issue to get a mob like Pedders to measure the thickness needed. They has the toe out and camber amounts on a screen when airbags were raised to 100 psi when the thickness of the spacer was determined. If for example the spacer was 20mm thick then I'd need to pump up the airbags say 20 pounds more to achieve max tread on the road. But then the ride would be too hard.

Now my tyres should last longer especially when towing the Guppy van

Update: I am dubious that 30mm spacers is enough. It is enough if I am happy to have the airbags at 60psi or 65. But if there is only my wife and I riding then 45 is more ideal/softer. Meaning I really need 50mm spacers at that pressure. Might fork out the $65 to get a second set of 20mm and add them to the 30mm spacers on there. Its all about minimising tyre wear and not having the rear end of the trike too ugly high.

Hope this also helps vW owners.

Personally I'd buy some IRS brackets, chop the poorly aligned original ones out and weld the new ones in at the correct angle.

You shouldn't have to have the airbag pressure so high to makes things OK as its a harsh ride and can make the trike less stable as it'll bounce instead of absorb road imperfections. That could make it dangerous to drive.

You can adjust neg camber on a IRS rear end without changing the height (adding spacers)....you just need to twist the IRS arm in relation to the spring plate......hard to explain via words so PM me your phone number and I can explain

thanks guys. I'm bit busy for next couple of days. Then I'll take a few pics of my IRS and post it here for your view.

The 30mm spacers as per the pics allow for the airbag pressure to be around 60psi...not bad and good for towing my van but still too hard for jus tthe two riders. If I palce 50mm spacers in there then prssure could be lowered to 45psi which would be real comfy.

That twisting idea of the IRS arm sounds good because that would keep the trike low....and it look far better the lower it sits.

^ yes I have done it and its amazing how much adjustment is available using that method. its also mentioned in the workshop manual so its the way camber is adjusted at the factory I am pretty sure.

here are some pics.





















oops...


where would you go to get the irs twisted?

any comments on the pics guys? if I can twist the swing arm and where I could get this done?

any answer to the above question please...I think its been overlooked. through to the keeper.

The twisting your talking about.... is that for camber change, if so, the twist is at the bolted connection between the spring plate and the torsion arm. Photos dont see the detail necessary, loosen the connection and try it.

Thanks Matt. Had a PM from another member also.

It is clearer now. the IRS swing arm isnt a standard set up. Panther trikes modify it and it isnt adjustable.

So dotn know about the twisting idea either.

What I do know is that when the body is raised by pumping airbags up to 100psi the toe out goes to where it is suppose to be and the camber also goes to an acceptable amount also. But of course the suspension is like concerte.

Enter the spacers. At 30mm thick the spacers allow the airbags to have less air. down to 60psi and have the same alignment effect with some softness in the ride.

What about 50mm spacers? I have ordered them. $30 each. This should allow the airbags to be lowered even more say 45psi- an ideal amount for a compromise.

Will fit them next week and show somw pics. I am getting new tyres in 4 weeks time and didnt want to wear out the insides again.

What tyres would Panther normally recommend for their kit then? Width and diamter wise?

Can't beleive they sell something without any adjustment possible to take into account ride heights, tyres and just basic suspension geometry adjustments.

Seriously the best way of doing this is figuring out the best ride comfort/height etc with the spacers and then having the lower airbag mount re-fabricated and welded on there so it's permenantly correct. Personally I don't like the idea of a long bolt thro a spacer for suspension parts.

thankd Psimitar

I hear you. I've worked out the ideal ride height from pedders. They put it on the wheel alighment machine and worked out the height for a tiny amount of positive camber. This height also found the correct toe in.

From there with the 30mm spacers and the ideal airbag pressure for 2 up riding I end up with some negative camber- just a little too mcuh for long wear from my tyres.

Hence the 50mm spacers. Then I'll have long wear and adjust the airbags for ride comfort. I pick up the spacers this week.

I was advised by pedders to drill a second hole or evena third to secure the spacer on the mount. Better still, once satisfied with the 50mm spacers- to get two slabs of alloy disks machined might be the go. I noticed that the spacers really should be a wedge shape to allow for the airbag ends to be parallel.

Panther designed the trike with 295/50 r15 tyres. I put on 275/60 r15 for longer legs when I had the aircooled engine in it. I'm about to replaced the tyres with 295's again. Panther trikes have no adjustment at all except the airbag pressure. And as you can see above you can get the camber and toe in correct but it takes a rock solid 100psi to do so. hence the spacers.

Thanks for all replies. I'll fit the 50mm spacers and let you know the result. Then set about seeking permanent spacers

I was hoping the wheel end of the swing arm would be able to be twisted to get the right camber without spacers and a lower ride height.

I know you are stuck with it now but that is a poor design as the hard the suspension goes the more twitchy the trike becomes.

Anyhow another idea is a camber shim behind where the bearing cover attaches with the caliper mounting bracket.

Thanks Psimitar. much appreciated = will look at that

ok things are clearer now.

I installed the 50mm spacers under the airbags. All its doing of course is jacking the body up. And I'm half happy. But I'd be happier with a proper fix.

The IRS system is not a VW system, the swing arms are alloy and made by Panther. There is no torsion bars, just airbags and a gT Monroe shockers. And disk brakes with twin calipers per wheel.

So without taking it all apart just yet I'm assuming the only way to fix the camber and the toe in is placing shims behind the disk. I've calculated each side's thickness of shims. might need to get them made up. They will also allow me to do away with the spacers and the rear of the trike will be much lower and more attractive.

have you checked if the arms are within spec? if they are out do you still have a warranty for the trike?

NOT behind the disk!!!

Take the spindle assembly apart and see how it goes together. What you want to do is change the angle the spindle sits at relative to the a-arm. Due to the spindles inner bearing the inner bearing face will probably need machining to the new angle the spindle and bearing will sit at. It's not the easiest of fixes but IF you have the trike set up as it will normally be used and at the pressure/ride height you like then once done you can forget about it.

Again I can't beleive this trike kit is sorry to say, SO SHIT!!! How can you sell something with no suspension geometry adjustment capability.

Maybe a simpler fix is to cut the A-arm where the 45degree weld is and make the angle change here. It's only ali welding and I could at least tack weld the A-arm after getting the angle correct and then have a pro welder do the seam weld.

if you need a picture of what I'm on about then you'll have to wait awhile as I've not got good PC use till maybe next week.

thanks guys. Yes, agree with you both here. "behind the disk" was a term used because I didnt know the real term, it meant in that general area.

I am disappointed with the amount of work I have to do to get it right but I've moved on from that.

The thing is that the passenger side (?) has double the negative cambers than the other side. Imagine a plate be attached at the end of the A arm. My rough measurements have indicated that to achieve 0 degrees camber I'd need to shim or machine 3mm off the bottom for the wedge shape and I'd need 1mm less at the front of it to achieve 0 tow in. And the other side half of all of the above. In fact the good side is almost passable. If they were both like that wheel I'd live with it.

1 degree toe in from what it is will achieve 100mm toe in over 6 metres. I had measured the toe out 3 metres forward and 3 metres back from the trike and the difference is 150mm toe out which equates to 75mm each wheel. So 1 degree will give it a litte toe in and that is acceptable in the VW IRS world according to my readings.

The 50mm spacers is a temp fix. They have halved the camber towards zero and a little less toe out. I've spent a fair bit on this trike and want to enjoy it a little before I dedicate my arthritic knees to more work on it. I know what I have to do now and yet again thanks to this forum I'm on the right track. When I get it done I'll post a full report.

Cool. Good luck with the proper fix and comiserations for having to be put in this position.

As a side note Oz does need to tightens a lot of it regs not just in vehicles and aftermarket gear but trades also.

Anyhow, all the best