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Richard saunders
05-02-2009, 09:14 PM
what pinion would u use on a 8.5 novak :drool:

emtee
05-02-2009, 09:27 PM
As a rule of thumb... 2-3 teeth less than the brushed equivalent... then check motor/speedo temps...

Richard saunders
05-02-2009, 09:38 PM
what would u use on a brushed then :confused:

emtee
05-02-2009, 09:59 PM
I think the 8.5 BL is around the same as 12-13 turn brushed...

Make the Final drive ratio to somewhere about 6.5-7.5 FDR...

To do this divide the spur teeth by the pinion teeth i.e.

Question: How do I figure out my final drive ratio (FDR)?

Answer: Divide the smaller gear (pinion) into the mating gear (spur).
Example: 108(spur) ÷ 24(pinion) = 4.5:1 (FDR)

If your car has a gearbox you need to know the gearbox reduction ratio. We'll use the Associated B2 ratio of 2.400:1 for an example.

Divide the pinion into the spur then multiply by the gearbox ratio.
Example: 85T (spur) ÷ 16T (pinion) = 5.3125 x 2.4 (gearbox) = 12.75 or 12.75:1(FDR)


What this means is that the motor makes 12.75 revolutions to every one revolution of the tire.

WHAT CAR U RUNNING...?

;)

jim76
05-02-2009, 10:12 PM
talk about over complicate something!

and that ratio in a micro is nuts!

Richard, simple answer, the smallest pinion you can get, a 10 tooth, and the biggest spur, a 49t.
But to be honest, the 8.5 is a bit loony for racing in a micro, especially at Wycombe. Turn down your throttle end point if you can!

Radish
06-02-2009, 09:00 AM
I agree with Jim, the 8.5 is seriously quick but start with 10/49 and see what your temps are like after a run.

By the way Jim, where have you been hiding, haven't seen you at Wycombe for a few weeks?

Richard

jim76
06-02-2009, 11:01 AM
i know. my focus died coming home from Tamworth to finish off a crap day!

had to scrap it for a new car. was scheduled to come this week but the snow put me off!!

Chris Doughty
06-02-2009, 03:33 PM
If your running an LRP Shark or FT Blaze with Touring car wheels on it then....

I run at 11/49, 10/49 would be safer.

they are right, it is nuts fast for micro racing, but I like lit :D

jim76
06-02-2009, 03:56 PM
they are right, it is nuts fast for micro racing, but I like lit :D

that's coz you're nuts! [and have a tad more skill than us!]

Richard saunders
06-02-2009, 05:19 PM
thank u 4 your help im runing the shark as doughty touring car wheels on it