11hp go kart gearing

[cooperDG123]

hey guys i got single person go kart with an 11hp engine i need help with gearing im thinking a three two one ratio. Is this a good ratio for speed. if my clutch has 12 teeth on it how many should my drive sproket be do i just multiply 12 by three to get a three to one ratio. any help would be ppreciated i need an answer quick

additional details

i only weigh 90LB
tires are 14inches
no jack shaft
11hp engine

 

[mysteryboy28]

bleep bleepin' bleepers. gotta love it when people correct their typos that you harassed them for. lol.

 

[mysteryboy28]

60-72 teeth is very common for axle sprocket. 60 for (eventual) speed, 72 for more torque. more speed = less torque. torque is good.

post your tire size, axle sprocket tooth count and clutch tooth count. if you have a jackshaft - post the tooth counts from that too.

and pictures. post pictures.

 

[OzFab]

3:1 will give you a massive top speed, but you'll never get there because you need a taller ratio (about 6:1) to accelerate. Running at 3:1 the only thing you'll manage do is burn out your clutch

 

[jman231994]

Yea you times the ratio by the clutch end to get your axle sprocket size

 

[klicky96]

If you are running a basic setup and have around 11"-15" tires, then you should run a 60T - 72T Axle Sprocket. The 72 will decrease your speed but increase you torque and give you a quicker take-off. With the 60, your still running at a safe ratio. But, you will get a low torque rate, meaning you won't take off as quickly. A difference of 12T can actually effect a kart greatly. When I run my basic kart. I run a 3:1 ratio, only because my tires are only 8". It depends on a lot of the weight and tire size.

 

[exenos]

with a 11hp and 14" tires you want around a 7:1 ratio if you need to go up minor hills and a 6:1 - 5:1 if it just for a flat area. I have a 6.5 hp and with 13" tiers and a 8.5:1 ratio. It has a hard time making it up the hill in my back yard.

 

[mysteryboy28]

i try to get a running start before climbing hills. my clutch appreciates it. lol.

 

[exenos]

That works great when the hill is smooth but not when it's a bumpy track. It's a little nerve wracking bookin it up a hill at 50kmh and fish tailing all over the place just too get to the top

 

[cooperDG123]

ok guys im kinda confused because i have another 5.5hp go kart with a 6 to 1 ratio and it climbs up hills very well and fast. so how could and 11hp have any trouble with a five or four to one ratio on the hills. These to karts are almost identical in size and weight.

 

[TheWingnut]

hey guys i got single person go kart with an 11hp engine i need help with gearing im thinking a three two one ratio. Is this a good ratio for speed. if my clutch has 12 teeth on it how many should my drive sproket be do i just multiply 12 by three to get a three to one ratio

Okay. This is how i have done my kart and this is how i have told many people to do it, and it worked for me. Now there are other ways, but this is how i got my sprocket sizes.

First, i go here. http://www.csgnetwork.com/tirerevforcecalc.html

I enter my specs. For example, you could put in 45mph, 8, and 5. I got about 746.9. Now i am going to take the rpm of the engine (the avg egine is 3600, but you should use the rpm of your engine if its different) and divide 3600 by 746.9. I got 4.81 (rounded) This is your gear ratio. Now that i have the gear ratio, i come here.
http://www.gokartsupply.com/ratios.htm
I found 4.81 under 11t clutch and the 53t final drive sprocket. And now you have your sprocket sizes.

And i understand you already have your ratio and a 12t cutch, but a 12 clutch is about average size so you can probobl still use that. And to minimize that gear ratio, u should also get a torque converter. It will give you much more power and they can help your ratio very very much.

 

[mysteryboy28]

4 to 1 ratio is baaaaad. 6 to 1 is already high, sucky for torque, decent for top speed. time to jackshaft it!

how many teeth axle sprocket do you have? please answer the question, we need facts.

 

[TripleT]

Does gearing depend on tire size also?

 

[exenos]

yes gearing depends alot on tire size

 

[CAPTAINCAVEMAN]

http://www.diygokarts.com/speed-calculator.html[/QUOTE]
this is very usefull when finding a ratio that fits your needs

 

[Jcotz]

I have a 1:5 ratio with a 6.5hp clone and 12 inch tires and it definitely pulls me well. I think you should have at least a 1:5 ratio.

 

[TheWingnut]

You have a lot of solution sggestions here. But i seriously think that recalculating everything would be a more efficint and precise way of getting what you need

 

[cooperDG123]

14inch wheels
5.5 honda gx160
12t on the clutch
72t on my axle
1inch axle
its pretty light
i weigh 90LB

 

[mysteryboy28]

14inch wheels
5.5 honda gx160
12t on the clutch
72t on my axle
1inch axle
its pretty light
i weigh 90LB

and on the 11hp kart? same tires? same sprockets? still 90 lbs, or are you fatter when you ride it? lol. eat a cheeseburger already.

 

[TheWingnut]

How did you get those measurements? Are you listing what you have or what you are saying you have come up with?