CarbonJoe

To those who haven't checked Novak's Tech pages lately, they have finally updated the Brushless Gearing Chart to add the 17.5. Boy, those are some huge rollouts for 1/12 scale. Better get a 78 tooth spur.

http://www.teamnovak.com/tech_info/b...r_gearing.html

AdrianM

iTrader: (4)

Those are conservative numbers too. I run my 10.5 around 57mm in my 1/12th with no problems.

cookie1

I think they are very conservative numbers for road cousre. I run road as well in 1/12th on the rug. I would look at the oval gearing as a closer bench mark. A titch high but closer.

trailranger

The 1:12 ratios looked a bit low, but brushless in 1:12 is fairly new compared to brushess in sedans and off-road.

Just gear up till: your lap times do not increase or your motor temp gets too warm.

kn7671

iTrader: (16)

The 17.5 is killing me, especially with the new Xray '008. I would need a 96 Spur, 46-47 Pinion to reach a 3.5 FDR, it that will even fit.

I know must of us found the a Stock SS13.5 motor needed to be geared around a 4.3 FDR, so I agree that Novak is being conservative. Let's just call it being safe.

trailranger

Novak being Safe with this chart...



Look at the original gear chart. That would make Novak look like Huckabee...too conservative.

RussB

4.5fdr on a 13.5 with the standard rotor in a rubber tire tc sounds about dead on to me...

3.5fdr with a 17.5? sounds like we need 78t spurs in sedan too on a losi that would be 100/53.

CRASH

iTrader: (26)

That is crazy for the 17.5! That is like a roll out of 56.2mm! I don't think I can even come close to obtaining that in my Cyclone. At least not without changing the internal drive ratio.

So is that correct then, we need to be rolling the 17.5 out at 56mm? Even on foams and carpet?

Thanks,

P2

iTrader: (15)

I've been running my 17.5 at a 3.9FDR and keep up w/the brushed 27s. Motor temps after 5 mins are in the 150*s, this is with 70* ambient temps. 3.5 FDR seems a little low.

BullFrog

iTrader: (4)

If you can't get the gear ratio you want just go to a different Spur? I've changed my internal gear ratio on my car but my teammate did his by just changing the Spur.( Corally PHI).I'm running the 1.71 overall with the 78 spur and he is running the 2.0 with a 52 spur. I've been running about a 4.5 gear ratio for quite awhile ( some times lower). When I get home I fiquire out what I've been doing by the chart.

Darkseid

iTrader: (9)

Conservative!?! Man, that 17.5 is insane. 3.5FDR? Come on man? My car can get to that gearing range easy, but I doubt the motor can take it.

I currently run a 4.02 final with my 17.5 with standard size rubber tires, and that leaves the external motor temp at about 130~134 after every run.

The moment I stepped it up a tooth and put myself at a FDR of 3.93, the motor temp shot up to 155~160 external temp, which means its a lot hotter than that inside the motor. So I immediately went back down to the 4.02FDR.

So how the heck do Novak see 3.5FDR as a 'starting point'?

smoke81

I shoot for about 160 on my 13.5's So I wouldn't worry about getting the external temp up to 160. (Right now mine comes off around 155-160 every round). Unless your motor starts fading at the end gearup!

CRASH

iTrader: (26)

I would like to how Novak came up with this 3.5FDR for a starting point. To me 56mm roll out is insane.

Dustin your 13.5 is still only rolling out around 44mm, this motor according to Novak wants to be around 56mm or 2.2 inches. That just seems a little crazy to me.

Later,

smoke81

The chart says I should be running a 4.5 fdr.. I'm at a 4.4...


I could hit the recomended fdr for a 17.5 pretty easy in my car as well Tony :-p

CRASH

iTrader: (26)

The 17.5 that is not the 13.5

You are pretty much wear Novak recommends.

Later,