Track Tac

driver gear

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goin green

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I ran 1/6 mile using 12/59 finished third ,wanting to get a faster through corners. Would going to a 11/56 be a good move ?
 
no. that will likely slow you down. faster through the corner would be 12 56 or a 13/62. it would give you more pull out of the turn but not through the turn. handling and tire selection is key to corner speed.
 
flattop1 said:
no. that will likely slow you down. faster through the corner would be 12 56 or a 13/62. it would give you more pull out of the turn but not through the turn. handling and tire selection is key to corner speed.
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only turned 5800 rpm getting off and on throttle would 12 56 or 13 62 give more rpms also
 
Sixth mile is 880 lf, is it Momentum track or tight turned out of the throttle ? What Class, Weight, and Motor are you running ?
If your at 5800 RPM on a 12-59 NO a 12-56 or 13-62 will NOT turn more RPM unless currently your gear bound and I dought that you are.
 
racing promotor said:
Sixth mile is 880 lf, is it Momentum track or tight turned out of the throttle ? What Class, Weight, and Motor are you running ?
If your at 5800 RPM on a 12-59 NO a 12-56 or 13-62 will NOT turn more RPM unless currently your gear bound and I dought that you are.
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flathead alky 384 weight
and was put in with clones
 
More info would help. Seems like the driver is smaller then it should be, but your RPMs are low. Did you mean your at 5800 coming off the corner or for a max? Why are you in the 50's for rear gear? I always preferred to be around a 65. If your kart is handling good and the track has any speed I would be looking at why the motor isnt turning more.

jmo
 
goin green said:
I ran 1/6 mile using 12/59 finished third ,wanting to get a faster through corners. Would going to a 11/56 be a good move ?
Click to expand...

Try it! With an 11/56 you're going to pick up some rpm's just because it's a higher ratio than a 12/59 (you need 11/54 to keep the same ratio). I would first try a 12/61 to just get that RPM without changing the driver size. If that is a good change then try the 11/56 and see what happens. If that 12/61 doesn't help then try a 11/54 and see what happens.
 
I think a good place to start would be for you to get a good gear ratio chart.
11/56 = 5.09
12/59 = 4.92
11/54 = 4.91
12/61 = 5.08
as you can see, in that ratio range, if you add one tooth to the engine, you need to change the axle gear by 6 teeth to maintain the same ratio. Not exactly, did but very close.

In all my years of racing, a bigger ratio number always meant a lower gear ratio. I don't suppose it makes a whole lot of difference what we call it, as long as we all call it the same. I suppose it comes from our automobiles. What we call low gear is always a bigger ratio number than high gear.

Changing from a 12/59 to a 11/56, because the 11/56 is a lower ratio, and might get you through and out of the turn a little faster, but you will need to pick up 200 RPM to be going the same speed on the top.

12/59@5800 RPM = 37.95 mph
11/56@6000 RPM = 37.95 mph
assuming 34" circumference rear tire.

What octane fuel are you using and what size Jets are in the carb? Do you know how many cc's there are in the combustion chamber?

From the desk of Al Nunley
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory. (Al Nunley)
 
He needs to switch to a gear that gives him higher RPM's. If he was on a flathead and only turned 5800 rpm's he is way too low
 
just adding gear will not always bring rpm's up.
If you add gear and do not gain the calculated or accepted rpm for that gear you have handling issue.
Which means you are way too tight.
GoinGreen wants to get faster through the corner. gear typically won't make you faster through the corner handling does.
More gear could help , its trial and error.
 
On a sixth mile track your Totally out to lunch running 11 or 12 driver unless the turns are paperclip real tight and your out of the throttle a good bite, If it's a momentum track you need a 14 driver, and yes sounds like your kart is way tight that's killing your RPM's and your corner speed.
 
goin green said:
how about a 13-63 would that be close
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how do you expect anybody to answer any of your questions without some feedback. The best way to get answers to your questions is to answer some questions.

From the desk of Al Nunley
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory. (Al Nunley)
 
alvin l nunley said:
how do you expect anybody to answer any of your questions without some feedback. The best way to get answers to your questions is to answer some questions.

From the desk of Al Nunley
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory. (Al Nunley)
Click to expand...

He's given plenty enough info to get feedback to help his problem.
 
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