Olley

for some reason i can't post a reply in my previous thread.

but here's where i need help...

first off. can someone explain what roll out is, i'm trying to work out a suitable gearing for my TC4 using an app on my Iphone called GearIt 2. quite useful (if you know how to use it!)

secondly, i can't get my diffs to run freely, they keep binding up on the gear that is connected to the main prop shaft, i have just noticed that the gears at each end of the prop shaft have different part numbers, does anyone know the difference!

i'm getting quite annoyed with this thing now, i just want it to work so i can go up to the pole hill circuit and wear out my old sets of tires! it's the perfect weather for it this week and I've missed every opportunity!

J.Elliott

iTrader: (22)

Roll out is basically the internal ratio of the diff gear to the tire, most touring cars have a roll out of 1.5 to 2.5. The roll out is multiplied by your pinion and spur gear ratio, that number is your final drive radio (fdr).

Sorry, but I am not familiar with the TC4. what you can try is remove the drive shaft and spin the front and rear diff separately and see if it is not a drive shaft spacing problem.

MarkA

iTrader: (21)

First, download the TC4 manual here and you'll be able to cross-reference any part# you might need to: http://www.teamassociated.com/pdf/ca...rtr_manual.pdf

The TC3/4 series of cars were known to occasionally, over time, get enough warpage in the composite chassis to bind the drivetrain.

Rollout is your gear ratio and final drive ratio while accounting for tire diameter as well. This thread is old but has the math involved: http://www.rctech.net/forum/electric...e-rollout.html The post above mine has an explanation of final drive ratio which is different from rollout