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Billy's Red Neck Theory Of Coefficient Coefficiencies,The Process. What's That In The Road...A Head

Discussion in 'Building tips' started by ratrodsrule1, Apr 11, 2020.

  1. ratrodsrule1

    ratrodsrule1 National Contender

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    That would be an axle head BTW.
    Coefficient : a number that serves as a measure of some property or characteristic, as of a substance, device, or process.

    Billy needs a Pro Legend for this one, or not. If a smaller axle is supposedly faster would reducing the OD of the axle head produce the same result ? A smaller head would reduce a tiny area of friction. BUT !! Would the friction coefficient of a smaller head diameter offset the possible gain of a larger lubed head surface against the outer hub face ?
    HMMMM !!
     
  2. Jupiter 2.9

    Jupiter 2.9 Workshop Leader Pro Racer

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    Larger axles more stable wheels.
    If you are seeing the .84 minimum, I think it's to keep the guys who can cut their own stuff from using needle axles & bushings in BSA wheels.
    The axle heads need to be polished where they contact the outer hub just like the rest. You can sand the heads to make sure there is no contact on the OD
    If you are trying to fit the head in the second step of the hub, I wouldn't bother, wider contact points ar more stable too.

    You need to concentrate on rear alignment, balance & wheel prep first, that's enough to worry about for now,
     
    Last edited: Apr 11, 2020
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  3. ratrodsrule1

    ratrodsrule1 National Contender

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    So larger axles do offer more stability therefore faster times ? Yes the minimum of .84 was the reasoning for the question. Thinking smaller meant faster. Thanks, am focusing on the items you mentioned but was curious about the axle size and OD of the head.
     
  4. Stumpm2

    Stumpm2 Pinewood Ninja

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    The axle head should be tapered so the wheel only makes contact on a single spot around the axle head. Axle head diameter does not matter with the taper as the wheel never touches the outer portion of the axle head.
     
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  5. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    Regarding axle shaft... the biggest you can get away with. Meaning vendor axles like 93t’s. Unless you are using strictly BSA. Basically the smaller the difference between wheel bore ID and axle shaft OD the better off you will be. Like Jupiter already said it will be more stable. It gives a smaller area in between axle and bore, less “wiggle” room.
     
  6. Roadrunner

    Roadrunner Pinewood Ninja

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    Here’s my question - the BASX rules state “no bearings”. No mention of bushings. Does this mean fill and drill is legal?
     
    Last edited: May 24, 2020
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  7. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    Just gotta ask this first... for clarification on your question...
    When you say “fill and drill”... do you mean the wheel bore? Need to know this intention before taking a shot at helping and giving insight.
     
  8. ratrodsrule1

    ratrodsrule1 National Contender

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    Got you thinking have i Mr. Jimmy ? Lol I know if you’re head split open a bunch of tiny PWD cars would roll out but welcome to the World of Wiley Coyote where the search for food and Hunger was his motivator the need of speed is ours. In Oklahoma they don’t have a wind sock at the airport they have a logging chain spiked to a fence post. When the chain is dangling in the breeze everything is normal but when the links begin to separate you may want to toy with the idea of seeking shelter.

    Having said that if you’re walking down the hall to the restroom and pass a guy going on the opposite direction that looks familiar and you discover it was yourself you may want to take a break.

    But when things are normal and mind cleared you’ll come up with more ideas that you can develop lol.......RRR
     
  9. Roadrunner

    Roadrunner Pinewood Ninja

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    Sorry. Yes, I was asking about the bore. Can I make it smaller to better fit a minimum sized axle?
     
  10. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    Ok that clarifies for me and lets me know how best to answer....
    NO... NEVER...NO NO NO.
    Unless you have the utmost high tech machines, perfectly calibrated for holding wheel just right, drilling a perfectly centered hole without ANY goofs or defects... the ability to have a drill bit spin with ZERO runout... don’t do it. Even if you do have all that capability don’t do it.
    Just buy good wheels for your foundation.

    Now don’t get me wrong... some guys do have the skill and ability with a lathe to cut real well. They make and cut their own unlimited and pro stock wheels but they have been doing this a long time and also they are starting from scratch the entire wheel. Taking an existing wheel and adding to it and then trying to “make” a smaller bore.... the amount of work and R&D and do-overs.... just buy good wheels. The main vendors buy in bulk and sort for good runout both laterally and circumference and also bore size. Then sell them at good prices. If you have to have stock BSA wheel that’s not modified do that. They all sell good wheels for the various “fatwheel” classes too.

    Just know that the slightest variance can kill speed. Trying to remake a bore without any variance... my gosh that is a serious undertaking. God bless you if you can pull it off though.
     
  11. DerbyBoyz

    DerbyBoyz Rail Runner Pro Racer

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    That would be considered adding material to your wheels, so no you can't.
     
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  12. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    Oh duh... that basically trumps it all. I was looking at the should you versus the real question of can you.

    Sorry Road Runner, I missed the “is it legal” part of your question... my bad
     
  13. Roadrunner

    Roadrunner Pinewood Ninja

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    So, not illegal. Just ill-advised?
     
  14. DerbyBoyz

    DerbyBoyz Rail Runner Pro Racer

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    Illegal
     
  15. Roadrunner

    Roadrunner Pinewood Ninja

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    Yeah. I thought that someone would be selling wheels with bushings if it was legal...
     
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  16. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    I obviously didn’t pay close enough to your question or I wouldn’t even have rambled off. :rolleyes:
     
  17. ratrodsrule1

    ratrodsrule1 National Contender

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    Roadrunner even though my post I’m late to the party. Forget about it. Buy the best wheels and .093’s you can afford and redouble you wheel/axle preps under OR room conditions. Verify you drill and let er rip tater chip.
     
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  18. Roadrunner

    Roadrunner Pinewood Ninja

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    Sorry about that. I didn’t intend to hijack your topic. I sometimes think I prefer building to racing. But I want to stay within the rules. Our pack rules state clearly that bushings are not allowed.
     
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  19. ratrodsrule1

    ratrodsrule1 National Contender

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    Hey Brother no problem. Everyone here wants to help, they’ve helped me to no end. Glad I could share something with you that I actually know something about.
     

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