FDR, gearing ratio's etc ???

S.A.W · **Posted:** Mon May 31, 2010 10:44:06

Hi,

Can someone please explain to me how to find the correct gear ratio's ? I've got a T3 using Speed Passion motor (13.5t) and esc. I've been giving a starting fdr of 4.3 but want to know how to check if this is correct ? So how do you check, do I do some laps then check temp, if so what do I check motor & esc ? and what should they be, then where do I go from there ? smaller/larger pinion or spur ? which way do I go, gear up or down ? Sorry for the newbie question but don't understand the whole setting/adjusting to get the optimum gear ratio/fdr. :oops:

Thanks.

Skiddins · **Posted:** Mon May 31, 2010 14:04:45

In general they say that if you want more acceleration you run a bigger spur, use a smaller spur for top speed.
This is nothing to do with the FDR.

You really need to ask on the forums about the track you are running on, or preferably the drivers there as they will have better knowledge.

If your going to do it by temp, then you need to run for a few minutes, then take the temp of the motor, bare in mind it will get hotter the longer it runs so provided it's still not too hot, you can gear up a little (fit a bigger pinion etc.)

Make sure you check the temp after a five minute run and don't run it right on the edge or you might melt something.

Does any of this make sense?

Skiddins

S.A.W · **Posted:** Mon May 31, 2010 18:43:49

Skiddins · **Posted:** Tue Jun 01, 2010 02:22:37

What Speed controller are you using?

If it's one of the latest mega timing speedo's then you may need to run a lower gear ratio like 5.5 or something.

I will ask some guys who raced there on Sunday roughly where their gearing was.

Skiddins

S.A.W · **Posted:** Tue Jun 01, 2010 08:56:56

S.A.W · **Posted:** Thu Jun 10, 2010 14:21:37

Skiddins, did you find out any info on gearing ?

Thanks.

Skiddins · **Posted:** Thu Jun 10, 2010 15:00:15

I seem to recall someone was on 4.7, using a Black Diamond ESC.
The others would normally be lower ratio's, around 5.5

Skiddins

S.A.W · **Posted:** Thu Jun 10, 2010 15:12:58

My motor manual says 4.8-6.0 should I be staying within these figures ?

Thanks.

Skiddins · **Posted:** Thu Jun 10, 2010 23:12:40

The motor manual, unless it gives specific guidance for tracks types, is useless.

It depends more on what your ESC does with regard to timing and boost etc. The problem there is that I know nothing about your ESC at all as I don't know anyone who runs one..

Skiddins

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FDR, gearing ratio's etc ???

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