Gearing Question for Junior Driver

I have a first-year 9-year-old driver that is running an LO206/blue slide class. I believe most drivers are on 14/60-64 front tooth and we are as well. I am considering dropping to a 13/56-60 to help with torque and drive off the corner as we are .4 to .5 off the top 2 and .3 off 3rd and 4th. We are normally turning 5600-5700 so we have about 200-300 before the rev limiter. Would dropping the front hurt him greatly down the straightaway or be very minimal? One turn is fairly sweeping and you can carry some speed but the other is pretty sharp and looks like he is getting beat out of that turn down the front straight.

Thanks in advance for the responses.
 
No. Wouldn’t hurt anything as long as it’s the same ratio. Don’t let people get you caught up in the gear game. Ratio is ratio. Yes a smaller front driver will help will pull but at the same time there are other ways to beat them in the turns. I would play with stagger first.
 

racing promotor

Moderator
Won't hurt in fact IF it gives more corner speed it will show up continuing down the straight, BUT more likely your little lacking of corner speed is just the fact your little 9 yr old being 1st year needs more seat time, Is the kart handling good ?
 

racing promotor

Moderator
I have a first-year 9-year-old driver that is running an LO206/blue slide class. I believe most drivers are on 14/60-64 front tooth and we are as well. I am considering dropping to a 13/56-60 to help with torque and drive off the corner as we are .4 to .5 off the top 2 and .3 off 3rd and 4th. We are normally turning 5600-5700 so we have about 200-300 before the rev limiter. Would dropping the front hurt him greatly down the straightaway or be very minimal? One turn is fairly sweeping and you can carry some speed but the other is pretty sharp and looks like he is getting beat out of that turn down the front straight.

Thanks in advance for the responses.
If your current gearing with the 14 front driver is 100 % correct switching to a 13 driver and keeping the same ratio will not pick up .4th to .5th, but yes it may help ever so slightly off the turn.
 

Kj26

Member
No. Wouldn’t hurt anything as long as it’s the same ratio. Don’t let people get you caught up in the gear game. Ratio is ratio. Yes a smaller front driver will help will pull but at the same time there are other ways to beat them in the turns. I would play with stagger first.
That is so wrong, ratio is not ratio, argue it all you want. I’ve tried them games and on an asphalt oval you can try a lot of things without worrying about the track changing.
 

alvin l nunley

Premium User
I doubt changing gears, but with the same ratio, is going to do much for you.
 
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alvin l nunley

Premium User
Do the math! You'll see that one tooth on the axle is about 100 RPM. Bigger gear more, smaller gear less, to be going the same speed. You see that's what everybody's running, I suggest finding out for sure.

Put one tooth on the axle, if you gain 100 RPM, you're going the same speed at the end of the straight. If not, you're going slower.

There's so much to learn, I almost feel sorry for beginners. It took me 3 years to start winning, I'm just slow.

After you get the gearing problem solve, there's a lot of other stuff to work on. Have you scale the kart? Do you have an air pressure gauge? Do you have a tachometer? What kind? Do you know where your clutch stall RPM is? Putting your engine on a dyno is always a good idea. Knowing your compression pressure is a good idea. This is your first year, if you get all the stuff under control, you're doing good.

Having right gear ratio is important, but only if you have this other stuff under control.

"Tuning is tough" (Al Nunley)
 
That is so wrong, ratio is not ratio, argue it all you want. I’ve tried them games and on an asphalt oval you can try a lot of things without worrying about the track changing.
We will have to agree to disagree but the ratio doesn’t change. Percentages do. People think they got faster from a gear change when in reality they moved percentages by moving the motor.
 

flattop1

Dawg 89
We will have to agree to disagree but the ratio doesn’t change. Percentages do. People think they got faster from a gear change when in reality they moved percentages by moving the motor.
I don't think your scaling %'s change enough with a inch or two
of fore and aft engine movment .
 

racing promotor

Moderator
But they change. A 18/63 or a 16/56 is still 3.5. The motor has no brain and it knows no difference. If speed changes because of a gear change and they’re the same ratio it’s because something else changed.
The TIRES are never the same, and track conditions are always changing and there's your biggest differences, but make no mistake you can pick up speed with gearing change as well, even if you just chalk it up to it was better suited to match the driver driving style.
 
I understand that this is not going to pick him up .3 per lap, as only experience, lines and throttle control is going to do that. My thinking is that a small front gear might help in recovery of some of these mistakes and at least get him more competitive and able to follow some top runs a little longer to gain knowledge. The kart setup is fairly neutral, and we both continue to learn and grow each week. I just didn’t want to do anything that would slow him down and frustrate him because of something I have done.
Thanks again for all the insights.
 

Kj26

Member
We will have to agree to disagree but the ratio doesn’t change. Percentages do. People think they got faster from a gear change when in reality they moved percentages by moving the motor.
Our percentages don’t, we run multiple chains and our motors never move more than a 1/4” either direction which doesn’t change scale numbers.
 

paulkish

old fart
Work on getting around the turns better and the straights will take care of themselves.

The net of it is if you are not able to reach your desired rpm or do and just need a little more at the end of the straight, ....

fix the corner before the straight

until you fix the corner throw some gear on it to use the little bit of engine you have left and then as you improve in the corner start taking gear off

Part of fixing the corner is being straight or positioned straighter on exit without taxing your engine trying to accelerate when you still have some turning to do

_________________________________
fix exit now when your driver is young because if you don't they will instead of grinding off speed, spin the heck out of their tires on exit if you move on to more hp
 

paulkish

old fart
Left out is how it relates to available hp, available grip, and the ability to maintain all precious momentum on the track.
Without including what I just referenced all the years of experience, all the math, and all the dyno info results are flawed.
The difference is about the application, not the math.
 
I have a first-year 9-year-old driver that is running an LO206/blue slide class. I believe most drivers are on 14/60-64 front tooth and we are as well. I am considering dropping to a 13/56-60 to help with torque and drive off the corner as we are .4 to .5 off the top 2 and .3 off 3rd and 4th. We are normally turning 5600-5700 so we have about 200-300 before the rev limiter. Would dropping the front hurt him greatly down the straightaway or be very minimal? One turn is fairly sweeping and you can carry some speed but the other is pretty sharp and looks like he is getting beat out of that turn down the front straight.
I don't know where the 206 engines make their power to state whether or not you'd want to utilize the RPM's that you're leaving on the table before the limiter. I'd concentrate on the RPM drops and work to keep them in the range of where your engine makes power. I suspect your RPM range will be less using the smaller clutch gear. Once you have confidence that your driver is staying consistent (not just lap times but RPM's as well) try dropping a tooth on the rear axle. I believe the advantage of the smaller clutch gear is better acceleration. Let's say that 14/56 and 15/60 yield the same lap time. The 14T is probably better off the corner but may suffer a bit compared to the 15T closer to the end of the straightaway. What happens if you go to 14/55? Do you still have better acceleration than a 15/60 off the corner? Will the lower gear ratio make it equal to the 15/60 at the end of the straightaway?
 
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