Page 1 of 1

Minimum diameter of axle

Posted: Fri Dec 21, 2018 10:35 am
by Speedster
The Mid America (.084) and others have a rule on the limit the size of an axle can be, If all other rules are followed, why is there a limit on the size the axle can be less then stock size. Since Doc. Jobe says Smaller axles do not go faster I fail to see a reason for the rule. Also, it seems like an unenforceable rule..
What am I missing?

Re: Minimum diameter of axle

Posted: Fri Dec 21, 2018 6:05 pm
by whodathunkit
Well Speedster,

Don't most stock BSA axles range from ( 0.088 to 0.086) in diameter.
Maybe the reason for the Mid America rule of a minimum of (0.084) is for the kids .. who spend a little to much time filing and sanding there axles.

Re: Minimum diameter of axle

Posted: Fri Dec 21, 2018 8:37 pm
by Speedster
The BSA axle is fairly consistent at .087 with it a bit larger if measured across the casting marks on the shaft. The only thing I can think of is if the Myth is believed that smaller axles go faster. The vendors all make larger axles for a reason. None of them make smaller axles. Why the rule? It had to be made for a reason or maybe it's like our District where we have a rule but no one can tell me why it was made. Orrrrr, we've always done it like that.

Re: Minimum diameter of axle

Posted: Thu Dec 27, 2018 2:04 pm
by Vitamin K
Small axles go faster if the bore is reduced in size accordingly, I believe.

Re: Minimum diameter of axle

Posted: Fri Dec 28, 2018 10:35 am
by Speedster
VK, that might be true. However, I doubt that any Scout Race, including the Mid America, allows changing the bore size to something smaller. As always, I could be wrong.

Re: Minimum diameter of axle

Posted: Fri Dec 28, 2018 11:51 am
by Vitamin K
Speedster wrote:
Fri Dec 28, 2018 10:35 am
VK, that might be true. However, I doubt that any Scout Race, including the Mid America, allows changing the bore size to something smaller. As always, I could be wrong.
Rules disallow things like bushings. They don't disallow bore treatments. It is possible one could use a "treatment" that would build up enough layers to narrow the bore. Examples might be layers of CA glue that were subsequently polished.

This is just speculation, but it's a lot easier to put calipers on an axle than it is to measure bore diameter. :)