Re: Drive Assembly Sprockets are Custom Bored
OK I have 2 things to say on this subject:
If you dont like what is in the kit, then be thankful you did not do FIRST in the past. This is by far the best quality and most useful kit ever provided.
If you don't want to buy an $80 custom sprocket, then don't. just use the provided 21 tooth sprocket on the gearbox output shaft. You will have to cut some pieces of PVC or aluminum tubing to do this. If you can't cut PVC or aluminum, you can buy a bunch of large washers at your hardware store.
You can also skip the sprockets that FIRST gives you to put on the wheels. In fact this might be a good idea because the provided wheels have low traction. This does require a bit of creativity and custom designing. You will need the following items:
Some 5" long 3/8" bolts for axles.
some wheels with bearings (3/8" bore).
some sprockets of whatever size you choose to use (1/2" bore is probably good).
some 3/8" bore 1/2" OD bronze bushings.
some small diameter bolts long snough to go through the sprockets and the wheels.
the ability to drill some holes through the sprockets and wheels.
Press the bushings into the sprockets, and place them on the shaft with the wheel. Drill holes through the sprocket and wheel. Bolt them together. Cut your spacers to position the wheel sprocket in line with the transmission sprocket. Put another sproket on the other side of the wheel. make a simmilar wheel, but with only 1 sprocket on it. run chain from the transmission to the wheel with 2 sprockets, run chain from the 2nd sprocket to the wheel with only 1 sprocket.
for a 4 wheel drive setup, this might cost you around $80 to $100, the same as your replacement sprockets. If you were to make your own drivetrain from scratch it would cost you well over $400, and maybe not be as high quality.
Good luck with the driving!