How big a 48 pitch gear can you fit
This was a curiosity for me. Chances are I will never fit such a gear. I did manage to fit my biggest 48 pitch 47 tooh pinion with a 90 tooth spur. That's a final drive of 3.50 (maybe for the inevitable 30 turn brushless, or for your top speed run with the 3.5 motor).
Here is what I would do to repeat the install. First mount the desired gear with one screw on the motor plate. You want to achieve two things. Gear clearance and a relatively low motor. I found it easier to insert the motor with gear attached and then put in the spur and belt adjuster unit. Get things close to right and mark the motor and motor plate so you can reassemble them in the same orientation.
I made a pointed 3 mm screw to locate the hole to be drilled. (This is a common machining aid, a transfer screw, that you can buy). Take the enbell off the motor attach the Losi motor mount plate in the desired orientation and run your pointy screw into a suitable hole in the motor from the inside of the endbell. One of the higher holes is more suitable with huge gears. The screw will mark the Losi mounting plate. Now center punch that mark, then drill .120 or slightly bigger. .125 is the is the drill in your Dremel kit. Mark the inside of the very front of the motor hole with red Marks A lot or whiteout. Put in the motor and turn the gear. Dremel a little plastic out for gear clearance. The small drum sander worked well. Done.
You will note a little notch I dremelled in the upper spur gear opening. This gives me clearance to use a standard L-shaped Allen wrench to adjust the gear side to side for a perfect gear mesh. Note the motor clamp reinforces this area so it is not too weak.
You can have more than one hole on this plate. It is not too important which two holes you select in the motor. No cost.
Stock Motor Racing
There may be some 17.5 TC racing developing in Houston. We meet Thursday. Races Tuesday Evening. I'll see if a sufficient number show.
I don't plan to do anything to the car except change motor and tires at this point.
Last edited by John Stranahan; 05-04-2010 at 07:42 PM.