Tire Help

[mms140]

I am thinking about putting 5 inch rims in the front and 6 inch rims in the back. However, there are a couple of things I am still unsure about. For additional information I am 120 pounds and my go kart is 5 feet long.
1. Should I put bearings in the front or back wheels for speed (I want the most speed possible).
2. Have chosen good rim sizes for maximum speed on pavement and sometimes on very flat grass.
3. Will aluminum rims make a difference in my speed.
4. When I put on my tires how much will that increase the diameter to and what type of tire should I use in order to gain maximum speed on pavement and still be able to go on short grass on occasion.

Thanks.
mms140

 

[OzFab]

1. Bearing in the front for sure. If you're running a live axle you can't have bearings on the wheels because they must be attached hard to the axle, but bearings on the axle, yes. If you're running a dead axle you will need beaings ont the non driven wheel.

2. Is that a question or a statement?

3. A little bit. Alloy wheels are used to improve handling, not so much to gain speed.

4. That depends on what tyres you buy. I don't know aout 5" rims but on 6" rims the most common tyres are 13" OD... unless you're using shifter cart wheels in which case, again, I'm unsure: you need to specify.

 

[mms140]

Sorry about #2 I meant to say have I chosen a good rim sizes for maximum speed on pavement and sometimes on very flat grass. Also, i am not using a shifter kart just a regular one. When you say 13'' tires are the most common what rims fit inside of those?

 

[landuse]

Sorry about #2 I meant to say have I chosen a good rim sizes for maximum speed on pavement and sometimes on very flat grass. Also, i am not using a shifter kart just a regular one. When you say 13'' tires are the most common what rims fit inside of those?

13" are generally what people would use. It does vary though. What gearing are you looking at? What have you got at the moment? Changing tyre diameter could affect the gering the kart already has

 

[mms140]

I have not setup a gearing system yet and have not decided what ratio I am going to use if I wanted a high top speed what ratio and tire diameter should I use.

 

[OzFab]

Sorry about #2 I meant to say have I chosen a good rim sizes for maximum speed on pavement and sometimes on very flat grass. Also, i am not using a shifter kart just a regular one. When you say 13'' tires are the most common what rims fit inside of those?

"6" rims" is not very clear. If you're using 6" rims from a shifter type kart then the tyres to fit would have an overall height of 10" - 11". If you intend to use 6" rims like those found on a riding mower or similar then the most common overall height is 13".

This rim http://www.bmikarts.com/item/6-Rear-Rim-260065-110
would take this tyre http://www.mfgsupply.com/gomini/gominitires/gominitires6/gominitires6turf/8-359.html

I've just given you 2 parts suppliers, have a look around these sites as well as this thread
http://www.diygokarts.com/vb/showthread.php?t=1180

 

[landuse]

I have not setup a gearing system yet and have not decided what ratio I am going to use if I wanted a high top speed what ratio and tire diameter should I use.

This will depend on many factors. A good ratio is generally between 5.5:1 and 6:1. You don't want tall tyres though if you want to go very fast. They rob speed and burn your clutch if you are not geared properly

 

[mms140]

So are 13 inch tires in the back and 9-10 inch tires in the front too large or is that a good size for a regular go kart (not a shifter)?

 

[OzFab]

So are 13 inch tires in the back and 9-10 inch tires in the front too large or is that a good size for a regular go kart (not a shifter)?

Have a look at my build:
http://www.diygokarts.com/vb/showthread.php?t=14613

Keep in mind this was built for my 8yo but the front tyres are currently 8" on 4" rims & the rear are 13" on 6" rims so you should be fine

 

[landuse]

So are 13 inch tires in the back and 9-10 inch tires in the front too large or is that a good size for a regular go kart (not a shifter)?

That should be fine