Fray Car Tuning
By Tim Leppert
Drive Train
OK, Here we go.
Up to this point, we have a rear end ready. We also enter into an area that is
VERY hard to explain in full. You kind of have to see and hear what is
happening. I will try to do my best to get you close.
Before I go into an explanation, I want to let you all know that there are
alternatives to all this, That is CNC machined gears.
The two manufacturers that I know of are:
Wizzard
http://www.wizzardho.com/Main.htm
R.T.H.O.
http://rt-ho.com/index.html
Both are great products and have a place in the racing world. I have used both
and I would rank them in order as I listed them. The RT gears are very high
quality and have a head start on Wizzard. They are the main choice for most Fray
racers.
The Wizzard product is a relative newcomer to the scene, but the quality matches
the RT offering. Wizard also beats the RT price. This is why I feel the nod
goes to Wizzard.
Both of these sets press on true and have a smallish center hole, making for a
tight fit on even the most worn out arm shaft. When pressing on the drive gear
(14t), don't press the gear on 'till all the play is gone. Only press on until
the shaft is flush with the top of the gear. This will prevent the gear from
pulling the comm away from the brushes (that one is VERY hard to diagnose).
If you use an unaltered press, you will be fine.
As for the driven gear (24), Take the rear shaft and pinion you chose from the
last installment, and begin pressing. As you get close to home, stop and feel
the play. You want this to be free spinning, but with little up and down movement.
Finally, install the idler, put 'er together, oil and spool it up.
STOP.
Install the idler upside down, and repeat.
STOP.
If one way sounded smoother, mark the top with a scribe.
That's all for now.
Next installment, choosing stock gears and
lapping/polishing the gear train
Previous Installment: Rear End Gearing