calling all monty's

[mudhen]

hey monty, you out there tonight?

xxoo mudhen

[Monty @ B.O.W.]

but I'd guess I missed you by a few hours. Whats on your mind?

[mudhen]

i have this 40 degree .510 x-12 arm that i got from downtown don. he claims that it is the bomb. what kind of set-up would you put it in ,if it was yours?

xxoo richard MUDHEN marnhout

p.s. i started using 80 pitch (9-48) and it TOTALLY transformed the kelly 12's that i bought from you last winter. they kept the high end, but gained massive torque down on the bottom.

[Gill A]

I am curious to know how you were able to ascertain that by using 80p gears your car accelerated quicker but kept the top end?
Did your lap times improve and if so by how many ^^^^.
Gill A

[mudhen]

the motor uses a .515 x-12 arm and thus is a little more of a torquer than smaller ones. so by dropping the ratio to 5.33 to one i was able to use the available torque.
as well, the tracks that i run on are pretty short-125--130 feet, so over -revving them is not a problem and i was able to get max accelleration at the "proper" point on the tracks. and though it is hard to explain, i find that 80 pitch gives me a finer feel for the car. using 64p, even if it has the exact same ratio. is more abrupt--i.e. harsher in terms of the on and off controller action that i encounter with short ,flat tracks.

xxoo richard MUDHEN marnhout:eek:

[Monty @ B.O.W.]

Richard,
The slightly smaller diameter on the new arm will allow for a bit more revs and therefore slightly lower ratio. I would try it first in your existing Kelly setup.

I'm well known for resisting the temptation to change many parameters simultaneously. You just don't learn anything that way. I can almost feel you agitating for a smaller airgap, but thats one parameter I try to leave as constant as I can. It will vary a bit because Kelly cans vary a little...

The fact that you made a BIG change in ratio and got better results is proof that you were way off to begin with, although you may well have overshot it some.

80 pitch gears were always a favorite of mine, but I tend to use 64 pitch anyway because I borrow motors from my team guys frequently and they aren't all going to change over at once. I notice how the entire New York wing racing crew is now using 72 pitch. No doubt the stragglers among them did it so they could mooch HP easier.

Finally, assuming that this armature is actually new (not pretested), there is no way anyone can assert that it will be especially fast based on looks alone. Hope springs eternal, though, so by all means give it a fair shot!