Discs wheels, setting camber and toe?

popeyethewelder.com/facebook questions

 

2012

  • Robin Cook – Setting up Camber and Toe. How do you do yours?
  • Alan Vidow – If you want to run camber. Set it up so the wheels do not scrub at all on Tarmac
  • Mark Sherlock – Thats for toe not camber Al. But it still applies, zero toe = no scrubbing noise when you roll the buggy on tarmac. Camber wants to be about 8 degrees, if I remember right, but i might be wrong lol I’ve got a cambered axle so it dont matter to me :o)
  • Stuart Mcgougan – Strong wheel and Zero camber makes setting toe in/out easy
  • Mark Sherlock – What do you count as a strong wheel tho?
  • Alan Vidow – One that doesn’t bend 😉
  • We now use a tracking plate. Rather than setting any tow we set to zero & they do not scrub & they roll really nicely. But on that note… Why do we run camber? (Doh no time to test running mine straight before the next race)
  • Mark Sherlock – I attached my axle and wheels, loosened the blue blocks and jumped up and down on the axle :o) Should really check it on a tracking plate sometime lol
  • Robin Cook  – What do ya mean by tracking plate.
    At the moment I’m running a cambered axle (cambered bosses) with my duros. Not through choice but I need to get longer threaded bolts in the stubs on my other axle.
    Running with a slight toe out which has eliminated the scrubbing I was getting. Just guessed by eye then tested on the drive.
    Guessing the principle of toe out is to cater for the curved profile of the tyres? Same principle as turning the front wheel of a motorbike the opposite direction to the lean?
  • Ken Shaw – Here’s the deal from a dirt track racing perspective. YMMV.

    There’s only one good reason to run any rear axle camber, to compensate for tire sidewall deflection under lateral load. If you don’t have much sidewall or run fairly high tire pressure, you don’t run the risk of losing contact patch as the tire sees lateral loading. Any degree of toe is merely to compensate for the resulting kingpin inclination and the tendency of the tire to follow an arc. In the case of a beach racer style tire on an 8″ rim, 1/32″ toe per degree of camber is about right. Additionally, once you have achieved the side load necessary to deform the tire, the contact patch is actually running true and a zero scuff static toe setting is actually inducing scuff under side load. In practical application, the scuff resulting from camber is so minor, it’s picking fly shi-bit from pepper IMO.

    For my application, the four wheel buggy with independent suspension, Camber and Toe play a far more significant role in turning radius, steering effort, control in rough terrain and handling at speed. Lateral loading is by far a secondary concern to handling characteristics and steering effort.

    If you are inducing rear axle camber to make up for a weak wheel/rim configuration, you’ve got much bigger problems in the offing, especially if you start thrashing about and shock loading the system.
  • Carlos Fandango – Explain to me why Camber is needed on GSX wheels for instance, I had some disc wheels a few years back and if they had not been cambered I would have worried about the wheels buckling when scrubbing speed off, but on solid GSX wheels I dont understand the reason behind it. Camber and toe are not needed on Landsegler Manufaktur wheels
  • Ken Shaw – Motor cycle wheels don’t see significant lateral loads because it’s virtually impossible to generate that sort of loading without high siding.  Bicycle wheels routinely “pringle” under side loading. Flat lander freestyle riders run wheels with twice the usual number of spokes to deal with the side loads and still have to true wheels regularly. Without having laid hands on a Landsegler Manufaktur wheel, my guess is they did the home work on spoke loading.
  • Stuart Mcgougan – Camber is used for 1 converting lateral load to radial load that some wheels/bearings deal with better and 2 to stop Tyre rolling off of the rim
  • Carlos Fandango – That’s it Stuart, I have heard that before and had forgotten, of course, the bearings, they will be under a tremendous amount of force compared to a big foot hub
  • Robin Cook – Seen tracker plates mentioned a few times. Guessing it’s A template so your camber/toe settings can be easily replicated.
  • Alan Vidow – But; how much load will a GSX rim take before bending?  Are the 4″ wide landseglers discs or an intermediate. Same contact patch as a Bigfoot lite.
  • Stuart Mcgougan – I’ve pushed them pretty hard in the buggy and think I noticed some flex but to be honest I expect this came from Tyre side wall and not mag spokes.  I’ve never heard of anyone snapping or bending one yet.
  • Carlos Fandango – Al, I would say if anything the same or less than a barrow
  • Stephen Webb – OK I’m going to ask the dumb question. What were the Disc wheels, of which there are a few kinds I appreciate, designed for originally?