pic: FRC 1771 Drivetrain

[R.C.]

Originally Posted by Brandon Holley

Thanks for the shout out akash.

While I am no expert, I did spend a considerable amount of time this past season working with belts. We used .200" pitch, .375" wide kevlar reinforced timing belts from www.sdp-si.com. We finally had a belt go down after the beantown blitz this year (2 regionals and 2 off-season events).

The thing about a belt is even though ours were kevlar reinforced, they are just plastic teeth. Keeping them tight will help a considerable amount, and I am pretty sure you guys did to have the belt(s) last as long as they have.

http://en.wikipedia.org/wiki/Fatigue_(material) <---- FATIGUE.

Fatigue is basically repeated stress over a relatively long period of time. Even though your belts may not have seen any greatly large shock loads, seeing small loads over an entire FIRST season probably fatigued the material in the belt enough that it finally broke.

Congrats on making it this far into a season before having to change them!

Hope it helps.

Brando

My bad, i was talking about fatigue of the belt. They are just plastic, belts are great if you can use them and chain is just a tad bit easier to maintain and good luck with whatever you go with. BTW, nice cad job.

[sdcantrell56]

Im hoping I can get this drivetrain under 30 lbs. I havent made one yet that could actually function that was that light. Im working on a single speed version in case there is no need for a shifter like this past year.