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Rear wheel cant a must?

Discussion in 'Wheels and Axles' started by Keith A., Mar 30, 2021.

  1. Keith A.

    Keith A. Pack Champion

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    Here’s my question. Due to council rules, we must use the stock axle grooves and keep 4 on the floor. I have finished my axle prep and I’m nervous to bend my own axles to cant the rear wheels. Is this a must for rail riding?

    the car is built so filling the gaps and drilling are not an option. Am I better off trying to run a straight car or should I continue with my rail rider with no rear wheel cant? Or suck it up and bend my beautifully polished axles? (I should note all I have access to is the old school hammer powered axle press)
     
  2. Gso125 Racing

    Gso125 Racing Workshop Leader Pro Race Winner Pro Racer

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    Unless you’re racing razor wheels then canting the rear wheels is a must. Try to use the straightest axels you have for the rears and don’t bend them. If you can’t drill with a jig take a sawzall blade and just lightly cut so you get your axel at 2-3deg of cant. I’ve used Elmers glue just to set them. If you can, bend your fronts so you can set your steering and keep your 4 wheels touching. I’ve used that axel bender a ton it will do the job if that’s all you have. Use that axel bender also to hold your axels to cut a k-house groove in the head with a dremel tool or hacksaw so you can adjust your axels. There’s other pros on here hopefully will chime in and can help you better than me. Good lucky
     
    Last edited: Mar 30, 2021
  3. Keith A.

    Keith A. Pack Champion

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    Sawing the grooves and using straight axles sounds like a solid option. I really don’t want have to bend those rears and dial them in.
     
  4. B_Regal Racing

    B_Regal Racing PWD Royalty Pro Racer

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    To re-iterate what GSO said, do not bend your rear axles. Scout axles are bent already straight out of the box and tuning the rear is almost a must (if you can). I have seen people test scout cars on my track and with a only a k-house groove in the rears axles, some have gained several tenths (not hundredths, but tenths) by tuning the rear axles. Bending rear axles will only compound the tuning problem. You could consider these:

    https://www.derbydad4hire.com/BSA-Speed-Axles-A-PBSA.htm

    They are essentially BSA axles (or as close as you can get to BSA axles) that are straight and deburred. You could use BSA axles, deburr them and ultimately get the same performance, these just save you a lot of work (and headaches); but I do understand they are not BSA axles from the box.

    If you must use BSA axles, buy 50 or 100 of them (https://www.derbydad4hire.com/Set-Of-10-BSA-Replacement-Axles-A-004.htm) at 10 for $1. To select good scout axles, chuck the axle up in a drill. You'll can which axles are bent and which ones are straight with the drill at low to medium speed. For the front axle, do not use the Derby Worx axle press to bend your front axle. Instead, give it to your closest competitor. Cut a bend groove in your front axle and use a hammer and screwdriver to bend it. I just the video of John bending a front axle with those simple tools.

    Slots make your tuning problem even worse than with BSA axles alone. You might consider drilling the rear with a jig (if you have access to one) at the stock locations and then recreate the slot below the drilled hole. It's a grey area to me and I do consider it within the rules. The canted rear helps the rear wheels migrate away from the car body towards the axle head where friction is less. It also gets most of the wheel off of the track.

    And while we are at it, clean wheels are fast wheels. Do not get graphite on your wheels. You might consider getting something like this to prep your wheel surface / edges and clean your wheels: https://www.derbydad4hire.com/Pro-Wheel-Tread-Cleaner-T-PWTC.htm
     
  5. Keith A.

    Keith A. Pack Champion

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    wow. I’ve never heard of cleaning the wheels before a race. Great to know. I’m using John’s BSAx axles and I’m super impressed with quality. That’s why I’m so hesitant to bend them myself. I’ll try my best to get the rear camber I need with stock grooves. Cub Scout motto and all.

    *after much deliberation, I think I’m going to fill the grooves with quick epoxy and drill them at 2.5 degrees with a jig. This is still using the stock grooves, although creatively. I think the rule exists mostly to keep everyone’s wheelbase the same, which we are doing.
     
    Last edited: Mar 31, 2021

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