Gearing Setup

[jkonline]

I am new to RC cars and have just started to look at the gearing on a b4 I recently purchased. On the b4 it already had a 100 tooth spur gear however I need to purchase a pinion gear and maybe a diffrent spur but the key thing is I am unsure of what ratio I need.

I am running a SS 13.5 Pro Stock Brushless Motor (http://www.teamnovak.com/products/br...ems/index.html) running off a 3300mha nimh battery and I plan to race it on an outdor astroturf at the tichfield track.

In the manual for the motor it says the following:

"SS-Pro 13.5 brushless motor 1-2 teeth lower pinion than normally used on 27-turn brush motor.”

However I don't know what the normal is (or where to find that info). I know how to work out the drive ratio but I am unsure in what range it should be in order not to break the motor.

Thanks

[emtee]

The B4 manual says with the kit standard 81t/48dp spur a Final Drive Ratio of around 9.5 is recommended... I use 23t pinion with 81t spur(both 48dp)which gives FDR of @9.1... I'm running a Novak 10.5 EX...

So I guess the answer to the Q is:- a FDR of around 9 -10 will be fine...

Is the spur 48dp or 64dp 'cos 100t/48dp seems a bit undergeared..i.e. faster acceleration but low top speed..(for a given pinion)

Drop onto the associated website and download the build manual... the info is in there...

I hope this helps, but if not ping me back...

[jkonline]

Hi I have had a better look now I am home (i.e. taken it apart and red the number on the side of the gear rather than a brief look this morning) and it is a standard 81t/48dp spur not 100.

This makes it all a bit simpler. I found this post http://www.rctech.net/forum/electric...4-gearing.html talking about the same set up that I have.

I think that a 23 or 24 pinion is the safe way to go to start with as the tack does not have many straights so top speed is not so important. People on the other forum have talked about going as down to 21 or up to 26.

Thanks and if anyone has any comments on this it would be good to here them.

[RichB]

In my B4 at the same track, I'm running 24/81 with a 23turn brushed motor (I think its 23 turn, it is 24 years old) and find that about right, so that should be fairly close towhat you want for a 13.5t brushless. I'm sure you can borrow a few pinions down there and find something that suits.

[jkonline]

I have purchased a 24 just to get me going (at the moment all the eclectics work but does not exactly go anywhere). I would be good to try a few out later though.

Hopefully by the weekend I will have the b4 fully running and get down to the track if not it will be the week after. All seems to be coming together now.