Sprockets and SAE Baja

[SSChevyManiac]

I was wondering if you guys, preferably the engineer types had any ideas of how to make a plastic or nylon sprocket work for my SAE Baja car. 10 horse Briggs through a CR80 5spd to a go-kart style spool. I have access to an engineer, sprocket company, and some materials I just want to do some research/brainstorming first. Any ideas? I want to use one on the ouput of the motor, the input and output of the tranny and also the main drive sprocket on the axle.

[squirrel]

Re: Sprockets and SAE Baja

Make the sprocket and chain very large!

Actually you can probably make a rough calculation of how much shear strength the material needs, if you know the torque output of the motor and the low gear reduction of the transmission, and you some idea of how much traction you have. Divide the maximum torque by the pitch radius of the smallest sprocket on that chain, and then divide this force by the number of teeth in contact with the chain, then divide this load per tooth by the cross sectional area of the sprocket tooth (this will be kind of tricky).

If it looks like it'll work, then you have to figure out the actual design of the parts, and this will probably be based partly on what manufacturing capabilities are available.

Also look at how the sprockets need to be attached to the output shafts of the engine and transmission, because this could be a limiting factor. Keyways in soft materials are not good. Splines are better.

[SSChevyManiac]

Re: Sprockets and SAE Baja

The problem with making the chain and sprocket LARGE is weight. Weight is why we are entertaining these ideas. I also saw one live behind a 120hp micro sprint, so I figure we can make it work with our measly 10hp.

[squirrel]

Re: Sprockets and SAE Baja

About what size chain are you thinking of using?

[SSChevyManiac]

Re: Sprockets and SAE Baja

We've got the car put away in the barn for the time being, we're redesigning last years car to save some work. I'll get specs when I can.