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Old 06-17-2012, 03:03 AM   #8461
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i am not confusing myself mate.....you will see that if you set your car to higher ratio number like 3.0 you will find you wont get as much wheelspin....the closer you go to 1:1 the faster acceleration you will have out of the corners.....

with extra speed comes extra acceleration.......
try it for yourself and see how it goes.....

as for years racing.....let me reword that, what other cars or classes have you run??

also what ratio are you thinking of running???
I have tested it a fair few times before. That is simply not the case.

Again I don't know why you are asking about my experience in rc racing. I'm not asking you to post up your experience because it doesn't matter.

I will be dropping the ratio to a 2.25:1 for the blinky car next.

Here is a real life example for you. Have you driven a manual car before?

Put the car in 1st gear and accelerate.
Put the car in 4th gear and accelerate.

The car in 4th gear will not accelerate as fast as in 1st gear. But it will hit a much higher top speed. Try spin the wheels in 1st and try spin the wheels in 4th. It is much harder in 4th gear.

You will find that a cars 1st gear ratio is around 3.1
4th gear ratio is typically close to 1:1

Last edited by J-PaP; 06-17-2012 at 03:27 AM.
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Old 06-17-2012, 03:21 AM   #8462
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How many balls do I need to run in the 3racing spur gear and do I need new diff rings?

If possible can someone provide me with links to what I will need? Appreciate all the help! It's a lot different from off road.
The more diff balls you can use the more the pressure is spread out among them and the less pressure you will need to use for the same amount of friction...all that makes for a smoother diff. I use the Xenon gears because it lets me use 16 diff balls in the outer diff ball ring.
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Old 06-17-2012, 03:34 AM   #8463
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Do you run at TQ?

As for pinions 30-35? Thanks for your help
If you are running at TQ in Chino with an F104, get the Kimbrouogh spur gear with the Murff Dog 1/8 ceramic diff balls. Good combo and Sean stocks both. That's what I run in my F104.

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Old 06-17-2012, 03:39 AM   #8464
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Originally Posted by J-PaP View Post
I have tested it a fair few times before. That is simply not the case.

Again I don't know why you are asking about my experience in rc racing. I'm not asking you to post up your experience because it doesn't matter.

I will be dropping the ratio to a 2.25:1 for the blinky car next.

Here is a real life example for you. Have you driven a manual car before?

Put the car in 1st gear and accelerate.
Put the car in 4th gear and accelerate.

The car in 4th gear will not accelerate as fast as in 1st gear. But it will hit a much higher top speed. Try spin the wheels in 1st and try spin the wheels in 4th. It is much harder in 4th gear.

You will find that a cars 1st gear ratio is around 3.1
4th gear ratio is typically close to 1:1
you cant compare these to a real car........i like your theory though.....
this is how it is...these cars are direct drive.....so the closer you go to 1:1
the faster it will accelerate, thats why you are having wheelspin....

after you try your 2.25:1 , please try 3.0:1 you might be surprised...
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Old 06-17-2012, 03:41 AM   #8465
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you cant compare these to a real car........i like your theory though.....
this is how it is...these cars are direct drive.....so the closer you go to 1:1
the faster it will accelerate, thats why you are having wheelspin....

after you try your 2.25:1 , please try my 3.0:1 you might be surprised...
Gear ratio is gear ratio...it doesn't matter if it is direct drive, TC, or even full sized car...the affect is the same because it is simple physics.

If you are noticing a drop off in speed below a numeric 3.0 then that is likely because you have over geared the motor. Different motors have different torque so finding the right gear to maximize both top speed and gear ratio is key to a good setup.
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Old 06-17-2012, 03:45 AM   #8466
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you cant compare these to a real car........i like your theory though.....
this is how it is...these cars are direct drive.....so the closer you go to 1:1
the faster it will accelerate, thats why you are having wheelspin....

after you try your 2.25:1 , please try my 3.0:1 you might be surprised...
Unfortunately you don't understand. Not really sure how else I can explain it to you. You are incorrect on the matter though.

It doesn't matter that the car is direct drive. It is the same case no matter what the drivetrain.

I have already done what you are saying. I started at 3.2:1 when I first put a 21.5 blinky setup in the car.
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Old 06-17-2012, 03:47 AM   #8467
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Originally Posted by InspGadgt View Post
Gear ratio is gear ratio...it doesn't matter if it is direct drive, TC, or even full sized car...the affect is the same because it is simple physics.

If you are noticing a drop off in speed below a numeric 3.0 then that is likely because you have over geared the motor. Different motors have different torque so finding the right gear to maximize both top speed and gear ratio is key to a good setup.
yes gear ratio is gear ratio , but you cannot compair a fuel motor and electric motors , the toque curve is totally differant

i wis running my F104 at ETS the guys were running around 2.5 , i liked mine at 2.1 the speed was a little better but i lost some corner out pull , this was for me faster
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Old 06-17-2012, 03:48 AM   #8468
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Originally Posted by InspGadgt View Post
Gear ratio is gear ratio...it doesn't matter if it is direct drive, TC, or even full sized car...the affect is the same because it is simple physics.

If you are noticing a drop off in speed below a numeric 3.0 then that is likely because you have over geared the motor. Different motors have different torque so finding the right gear to maximize both top speed and gear ratio is key to a good setup.
exactly.....ratio is king.....we have found that 3.0:1 on our track is great.....
i am racing against sakura fgx's...not only am i keeping up with them, but i am actually faster than them down the straight...

the only downside is that if my diff is not exactly set right, they will kill me out of the corners......(dam those gear diffs)
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Old 06-17-2012, 03:54 AM   #8469
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yes gear ratio is gear ratio , but you cannot compair a fuel motor and electric motors , the toque curve is totally differant

i wis running my F104 at ETS the guys were running around 2.5 , i liked mine at 2.1 the speed was a little better but i lost some corner out pull , this was for me faster
You are correct in that internal combustion engines and electric motors do have different torque curves...but regardless the effect is the same. A higher numeric gear ratio number yields more acceleration and more torque to the wheels which gives you a higher probability of having wheel spin. If that were not true than the old Aevox powered speed run cars geared at 1:1 would not have needed a push start but they did.

As you said the 2.1 lost some pull...2.1 has more top speed and less acceleration than 2.5 and that is why you lost some pull. Your overall lap time may have been faster at 2.5 but top speed is faster at 2.1.

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Originally Posted by blade072 View Post
exactly.....ratio is king.....we have found that 3.0:1 on our track is great.....
i am racing against sakura fgx's...not only am i keeping up with them, but i am actually faster than them down the straight...

the only downside is that if my diff is not exactly set right, they will kill me out of the corners......(dam those gear diffs)
On your track 3:1 is good...but that may not hold true for all tracks. A 2.5:1 would still yield higher top speeds and less acceleration though if your track was long enough to take advantage of the gearing. 3:1 is still going to have a higher probability of generating wheel spin than 2.5:1 would.

Also you should be faster that the FGX down the straight...you have only 1 gear mesh where the FGX has 3 so you have a lot less drag than they do...Not to mention you should also be significantly lighter than the FGX which will also make you faster down the straight.
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Old 06-17-2012, 03:57 AM   #8470
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Originally Posted by J-PaP View Post
Unfortunately you don't understand. Not really sure how else I can explain it to you. You are incorrect on the matter though.

It doesn't matter that the car is direct drive. It is the same case no matter what the drivetrain.

I have already done what you are saying. I started at 3.2:1 when I first put a 21.5 blinky setup in the car.
oh i understand, and what was your car like at 3.2:1????
what esc/motor are you using????
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Old 06-17-2012, 04:01 AM   #8471
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Hi all, we just had our first ever race in Finland. Sadly only 4 cars and one had to quit after qualifying.

(Formula1 class was a demo class and run in the spare time at the VTR(that is our version of the vta class over the States) and Tamiya Mini summer cup day . classes

But remaining 3 had a race and every1 had a good time, spectators loved it and next race will have more racers.

All 4 cars were tamiya f104 based,X1,PRO,WGP,Mclaren. Diffferent gearing,motors,tires... -and still the racing was tight.

We had 2 (8min) A finals,I won the 2nd final (and the whole GP), first final went to Jonni driving the mclaren (because I swerved his flipped car and hit the track barrier),the onboard footage is from my car(F104X1 Lotus Renault).

I had to ditch the heavy(almost 20 grams, lol)cam from 2nd race, I just had to make sure I will win

both finals here if interested:
http://www.youtube.com/watch?v=KbFpX4YndrM

http://www.youtube.com/watch?v=hEt8mzeV0zM
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Old 06-17-2012, 04:05 AM   #8472
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oh i understand, and what was your car like at 3.2:1????
what esc/motor are you using????
lrp qc3 and a revtech 21.5

It was exactly as I have said a number of times now. It would accelerate harder (spinning the wheels easier) but have less top speed.

At 2.4 it spins the wheels less and has a higher top speed.

I'm really saying the same thing over and over....

By the way are you thinking of a car being faster with a higher gear ratio because that is what was giving you better lap times around the track?
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Old 06-17-2012, 04:18 AM   #8473
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lrp qc3 and a revtech 21.5

It was exactly as I have said a number of times now. It would accelerate harder (spinning the wheels easier) but have less top speed.

At 2.4 it spins the wheels less and has a higher top speed.

I'm really saying the same thing over and over....

By the way are you thinking of a car being faster with a higher gear ratio because that is what was giving you better lap times around the track?

you are correct....i should be the one with the wheelspin
and yeah i left it at 3.0:1 because it felt good to drive.....having said that looks like i might be changing my ratio...
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Old 06-17-2012, 04:20 AM   #8474
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it simple, if you want less wheel spin pull the trigger softer

same goes for getting faster times, stop messing with ratios and put the car 1/2 a meter closer to the apex.

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Old 06-17-2012, 04:23 AM   #8475
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Originally Posted by InspGadgt View Post
Also you should be faster that the FGX down the straight...you have only 1 gear mesh where the FGX has 3 so you have a lot less drag than they do...Not to mention you should also be significantly lighter than the FGX which will also make you faster down the straight.
we have a couple of highly modified carbon fibre FGX's
but it makes for some great racing
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